Subterranean Conduit Cover

Cross-References to Related Applications

This application claims priority to, and is a continuation-in-part of, US patent application serial number 11/811,849 filed June 12, 2007, which is currently still , pending, the entire contents of which are herein fully incorporated by reference.

Technical Field

This disclosure relates generally to covers useful for covering openings. More particularly, in one embodiment, it relates to closure devices for covering the end portions of conduits having interior spaces which may contain plumbing controls.

Background

Access conduits are frequently employed where it is desired to have access to a control device, such as a valve associated with, for example, a sprinkler system in a residential or commercial lawn or other agricultural setting, hi such applications, there typically exist a network of pipes through which water may flow during the normal course of providing irrigating water, and often it is convenient for field technicians to have the ability to control water pressure for a particular segment of an irrigation or sprinkler system. There are often cases where it is desirous to have a shutoff valve disposed along a distribution line in such a system, in a subterranean location. Accordingly, to protect control equipment such as valves from corrosion or other attack by the elements over time, subterranean conduits have been developed, which are generally enclosures which may be buried in the ground, and within the confines of which a control device such as a valve may be housed to be protected

from environmental factors. It is desirable for a field technician to have ready access to such valves, and typically the opening at the terminal end of a tubular access conduit has a flat lid which is placed over it, which may be removed as desired.

Summary of the Disclosure

Covers useful for covering an open portion of an access conduit are provided. In one embodiment, described in this paragraph, the covers include a substantially- circular, disc-shaped base portion having a top surface, a bottom surface, and a circumferential edge. There is a circular rib disposed on the bottom surface of the base portion. The circular rib itself has a top surface which is in a raised disposition with respect to the bottom surface. The circular rib forms a ring of raised elevation on the bottom surface. There are a plurality of risers attached to and extending upwardly from the circular rib and away from the bottom surface of the base portion. There are also a plurality of contact shoes, each of which contact shoes are attached to one and only one of the risers. The contact shoes have a convex outer surface, and a curvature which is non-coincidental with the curvature of the circular rib, when the cover is viewed from a bottom perspective view.

Brief Description of the Drawings

FIG. 1 shows a perspective view of the bottom of a cover according to one embodiment of the disclosure;

FIG. 2 shows a bottom view of a cover according to one embodiment of the disclosure;

FIG. 3 shows a side perspective view of a cover according to one embodiment of the disclosure;

FIG. 4 shows a perspective view of the top of a cover according to one embodiment of the disclosure;

FIG. 5 shows bottom view of a cover according to one embodiment of the disclosure; and

FIG. 6 shows a side perspective view of a cover according to one embodiment of the disclosure and its relation to an opening in a conduit which it covers.

Detailed Description

Referring to the drawings, and initially to FIG. 1 there is shown a perspective view of the bottom of a cover 10 according to one embodiment of the disclosure. In this FIG. 1 there is shown the base potion 3, which exists substantially in the form of a circular disc, having a bottom surface B, which in one preferred form of the disclosure is flat. Attached to the bottom surface B of the base portion 3 is a circular rib 5, which is disposed to protrude or project upwardly from the bottom surface B. In one embodiment, the circular rib 5 has a rectangular cross section and has a top surface T. In one embodiment, the top surface T is planar and is substantially parallel to the planar bottom surface B of the base portion 3. In one preferred embodiment, the circular rib 5 is disposed so as to form a ring, which ring may be located at any point between the center of the base potion 3 and the outer edge of the base portion 3. In a preferred embodiment, the circular rib 5 is disposed to be present on the bottom surface B of the base portion 3 at any location that is distanced between about one- twelfth of the radius of the base portion 3 and three- fourths of the radius of the base portion 3, from the outer circumferential edge of the base portion 3. For example, in one embodiment, when the base portion 3 has a radius of 10 centimeters, the circular rib 5 may be disposed at any location that is between about ten-twelfths (10/12) centimeters from the outer circumferential edge of the base portion 3, and 7.5 centimeters from the outer circumferential edge of the base portion 3. In one preferred embodiment, the base portion 3 has a radius of 10 centimeters, and the circular rib 5 is disposed at a location that is about 3 centimeters from the outer edge of the base portion. The location of the circular rib 5 from the circumferential edge of

the base portion may be measured from any point on the top surface T of the circular rib, including the inner edge, outer edge, or any point therebetween. In one embodiment, the circular rib 5 has a width dimension of between two millimeters and four centimeters, as viewed from its cross-section. This width dimension is also the width of the top surface T of the circular rib 5, when its cross section is rectangular, as in one embodiment. In one embodiment, the width of the circular rib is between about two millimeters and ten millimeters wide. In a preferred embodiment, the circular rib 5 has a width dimension of about four millimeters, as viewed from its cross-section, corresponding to the width of its top surface T and the cross section is rectangular, the circular rib being disposed so that the midpoint of the width dimension of the circular rib 5 is distanced at a point about three centimeters from the outer circumferential edge of the base portion 3.

Disposed at the top surface T of the circular rib 5, and equally spaced thereabout, with regards to one another along the circular rib 5, are a plurality of risers 9. In one embodiment, the risers 9 extend upwardly, and in a direction that is away from the bottom surface B of the base portion 3, and can also be viewed as protruding upwardly from the circular rib 5, as shown in FIG. 1. The risers 9 are contoured to have a curvature, which substantially matches, and in one embodiment has congruent curvature with the circular rib 5, which embodiment having such congruent curvature can be seen readily from the bottom view in FIG. 2. In one embodiment, the risers 9 are each substantially triangular as viewed from a side perspective, with one of the legs of these triangles so defined being attached to and co-extensive with a segment of the circular rib 5, with the remaining leg of these triangles comprising intersections 13 , each of which intersections 13 having disposed thereabout a contact shoe 11. The intersections 13 in one embodiment permit some movement of each of the contact

shoes 13 independently from the relatively stationary position of the risers 9. FIG. 1 also shows a plurality of rib segments 7, extending from separate points on the inner wall of the circular rib 9 to a common center hub 17 at which the rib segments intersect, the center hub 17 being shaped in one embodiment in the form of a cylindrical solid and also being disposed on the bottom surface B of the base portion 3 as shown. The rib segments 7 may in one embodiment be analogous and identical to the circular rib in construction and cross-section, differing therefrom only in that they are linear, and are not disposed on the bottom surface B of the base portion 3 so as to form a ring thereon, but rather are disposed in the interior space defined by the circular rib 9, as shown. The rib segments 7 and center hub 17 provide added strength to the cover 10. There is also a hole 15, disposed through the base portion 3, which enables a user to lift the cover from an installed position by inserting their finger through the hole 15 and pulling the cover upwards, off of the opening which the coer 10 covers. The dotted lines in FIG. 1 show alternate embodiments of shapes of the risers 9 according to alternate embodiments, when the risers 9 are viewed from the side perspective, including risers having rectangular and smooth-curved surfaces, in addition to embodiments in which the risers 9 appear substantially-triangular as viewed from the side, as described below.

A cover 10 according to the disclosure is preferably comprised of a material having a reasonable strength, and suitable materials include stainless steel, steel, aluminum, any metallic alloys, polymers, polyethylene, polypropylene, alpha olefin copolymers, thermoset resins, thermoplastic vulcanizates, fiberglass, wood, composites, pressed wood fiber composites, graphite composites, etc. It is especially preferred that a device according to the disclosure be fabricated from an injection- grade polypropylene, based on its strength and durability, with virgin polypropylene

being especially preferable. However, any material having strength sufficient to enable a cover according to this disclosure to support about 150 pounds placed on its top surface without undergoing fracture when installed at the terminal end of a conduit at ground level is generally suitable for use in providing a cover 10 according to the disclosure. When polyolefins are employed as the material of construction, it is possible to provide a cover 10 according to one or more embodiments, in which a cover 10 as shown in FIG. 1 is made of unitary construction, that is - wherein all elements described above are present on a single injection-molded piece. Thus, the cover 10 shown in FIG. 1 , in one preferred embodiment, is a single molded article. hi FIG. 2 is shown a bottom view of a cover 10 according to one embodiment of the disclosure. The respective locations of the base portion 3, circular rib 5, risers 9, and contact shoes 11 are shown, as well as the rib segments 7 and center hub 17. Also shown are the intersections 13, which are the locations at which the contact shoes 11 are attached to the risers 9. In this embodiment, the risers 9 are contoured to have a curvature which substantially matches that of the circular rib 5. hi one embodiment, the contact shoes 11 comprise an outer convex surface, and an inner concave surface, and the contact shoes 11 overall contour collectively departs from coinciding with the circular rib 5 as viewed from the bottom view of FIG. 2, as shown therein. Having the contact shoes 11 contoured in such fashion, coupled with their being attached to the risers 9 at the intersections 13 permit some movement of each of the contact shoes 13 independently from the relatively stationary position of the risers 9 in a direction shown by the double headed arrow depicted in FIG. 5, which movement is generally describable as being towards and away from the center of the base portion 3. By such configuration, the contact shoes 11 can each be pushed slightly towards the center point of the base portion 3, and when this is done, they will

resist such pushing slightly and have a slight mechanical bias back towards their original position. This effect is of utility, when the inside diameter of a portion of a conduit which is desired to be covered is slightly less than the diameter of an imaginary circle drawn to be tangential to each of the contact shoes 11, for in such case, one may push or compress the contact shoes inwardly towards the center point of the base portion 3, and insert the cover having the contact shoes 11 so compressed into the conduit, so that the bottom surface B of the base portion 3 is facing the interior of the conduit. Upon release, and after being so positioned at an opening of a conduit, the contact shoes, by their inherent mechanical bias, from the energy stored by their compression, will exert a force that is oriented in a direction that is pointed outwardly from the centerpoint of the base portion 3, towards the inner wall W (FIG. 6) of such a conduit, until the contact shoes 11 contact the inner wall of the conduit, thus providing a securing force for the cover 10 in its installed position at the terminal end of such a conduit or enclosure. In FIG. 3 is shown a side perspective view of a cover 10 according to one embodiment of the disclosure, showing the respective locations of the base portion 3 and its top surface S, the circular rib 5, risers 9, contact shoes 11, and intersection 13. In one embodiment, the convex surfaces of the contact shoes 11 may have a texture on them, which texture may include knurling or ribs 19, cast or machined onto the convex surface of the contact shoes 11. Although described as being shaped substantially triangular as viewed from a side perspective such as that in FIG. 3, the risers 9 may have other shapes as well, including rectangular, or any irregular shape, with a main proviso, in one embodiment, being that the risers 9 should be connected to the circular rib along one of their edges, and should also have a contact shoe 11 disposed at another of their edges, so that the longest length dimension of the contact

shoe is disposed to be substantially parallel to the bottom surface B of the base portion 3.

FIG. 4 shows a perspective view of the top of a cover 10 according to one embodiment of the disclosure, showing the respective locations of the base portion 3 and its top surface S, riser 9, contact shoes 11 having texture ribs 19, and intersection 13. Hole 15 is shown, as well as optional surface texture 21. The optional surface texture 21 may be any irregularity on the top surface S, including depressions, or protrusions, in any shape, including cross-hatchings, knurling, or depressions or protrusions of any geometric shape disposed in any pattern on the top surface S. In FIG. 5 is shown a bottom view of a cover 10 according to one embodiment of the disclosure. In this embodiment, the respective locations of the base portion 3, circular rib 5, risers 9, and contact shoes 11 are shown, as well as the rib segments 7 and center hub 17. Also shown are the intersections 13, which are the locations at which the contact shoes 11 are attached to the risers 9. From this view, the risers 9 are seen to be contoured to have a curvature which substantially matches that of the circular rib 5. In one embodiment, the contact shoes 11 comprise an outer convex surface, and an inner concave surface, and the overall contour of the contact shoes 11 collectively departs from coinciding with the circular rib 5 , as compared with the risers 9. Having the contact shoes 11 contoured in such fashion, coupled with their being attached to the risers 9 at the intersections 13 permit movement of each of the contact shoes 13 in a direction shown by the double headed arrow, which potential movement is generally describable as being either towards or away from the center of the base portion 3. By such configuration, the contact shoes 11 can each be pushed slightly towards the center point of the base portion 3, and when this is done, they will resist further such pushing slightly and acting analogously to springs, each will have a

slight mechanical bias back towards their original position following application of an unbalanced force, such as pushing. This effect is of utility, when the inside diameter of the terminal portion of a conduit which is desired to be covered, such as that diameter defined by dashed circle Ci, is slightly less than the diameter of an imaginary circle drawn to be tangential to each of the contact shoes 11 when in their equilibrium position (with no force applied), such as dashed circle C ₂ , for in such case, one may push or compress the contact shoes inwardly towards the center point of the base portion 3, and insert the assembly having the contact shoes 11 so compressed into the conduit (FIG. 6), so that the bottom surface B of the base portion 3 is facing the interior of the conduit. Upon release, and after being positioned within the confines of the opening of such a conduit, the contact shoes, by their inherent mechanical bias, from the energy stored by their compression, will exert a force that is oriented in a direction that is pointed outwardly from the centerpoint of the base portion 3, towards the inner wall W (FIG. 6) of such a conduit, until the contact shoes 11 contact the inner wall of the conduit, thus providing a securing force for the cover 10 in its installed position at the terminal end or opening of the conduit. Shown in FIG. 5 also is the locations of hole 15.

According to an alternate embodiment of a cover provided herein, the segments of the circular rib 5 containing hash marks in FIG. 5 may be omitted, in which embodiments the circular rib 5 will then instead be replaced with a plurality of rib segments, each of which rib segments have a riser attached thereto, and a contact shoe attached to the risers, as hereinbefore described. The location of such rib segments so resulting may be disposed in any location earlier specified for the circular rib itself, with respect to the outer circumferential edge of the base portion 3.

FIG. 6 shows a side perspective view of a cover 10 according to one embodiment of the disclosure and its relation to an opening in an access conduit 12 which the cover 10 is intended to cover. The access conduit 12 is typically disposed in a subterranean location, with its terminal end or lip portion 23 being at or near ground level, as is known in the art. The conduit 12 has an opening 25, at its terminal end. In typical installations, there is disposed within the conduit a control device, which may be a switch, valve or the like. In FIG. 6, the control device is a valve 31 having a handle 27, which controls the flow of water through pipe 29, which may be a water pipe. In one embodiment, the lip 23 of the conduit 12 is contoured to be capable of receiving the circumferential edge of the cover 10 so as to render the cover / conduit assembly to have a flat top surface, with the top surface S (FIG. 4) of the base portion comprising that flat top surface. The opening 25 of the conduit 12 has a diameter dimension that is exemplified by the points Oi and O ₂ which are disposed at opposite points along the opening of the terminal portion of the conduit. In one embodiment, the distance between points Oi and O ₂ of the conduit 12 corresponds to the diameter of dashed circle Cl in FIG. 5. However, dashed circle Cl shall not be construed as being a boundary of the movement of the contact shoes 11, and the scope of their motion includes extension inwardly all the way to the circular rib 5. Thus, to install cover 10 onto the opening of the conduit 12, one may manually press the contact shoes 11 inward towards the center hub 17 of the cover 10, and place the portion of the cover 10 which comprises the contact shoes 11 into the opening of the conduit. The pressing on the shoes is released, thus causing the contact shoes 11 to press outwardly against the wall W, securing the cover 10 fixed in position by the outward mechanical bias of the contact shoes 11. The cover 10 is then pressed downward so that the circumferential edge of the base portion 3 rests within the lip

portion 23 of the conduit 12. To remove the cover 10 from a conduit once installed, one merely places a finger through the hole 15 (FIG. 4) and pulls the cover 10 away from the conduit 12. A twisting motion may be optionally simultaneously applied to the cover 10 during such removal, or installation. Although shown and described as having three combinations comprising risers

9 and contact shoes 11, alternate embodiments of a cover 10 include embodiments having two, four, five, six, and more of such combinations disposed along a circular rib 5 as described herein. Preferably, but not necessarily, such pluralities of risers and contact shoes are spaced equidistantly from one another along the circular rib 9. In further alternate embodiments, the contact shoes 11 appear linear, when said cover is viewed from the bottom perspective. That is, the contact shoes do not have a convex outer surface and concave inner surface, but rather comprise an inner surface and outer surface, each of which is substantially flat. In one embodiment, the inner surface and outer surface on such flat contact shoes comprise planar surfaces which are substantially parallel to one another. In various alternate embodiments, the contact shoes may have essentially any contour when the cover is viewed from the bottom perspective, provided that they are configured and disposed to be capable of contacting the inner wall of a conduit which a cover according to the disclosure is engaged or covers as herein described, in a way which enables the contact shoes to exert a force against the inner wall of such conduit sufficient to substantially maintain the cover in a stable position. In these various embodiments within the description of this disclosure, each of the contact shoes are attached, as in other embodiments, to a riser.

It is understood that modifications are allowable within the scope of the disclosure. The disclosure has been described with specific reference to the preferred

embodiments and modifications thereto. Further modifications and alterations may occur to others upon reading and understanding the specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the disclosure.