TECHTJICAI, -flEIP

The present invention relates to trench components and, more particularly to a trench cover assembly whereby the cover member is held captive by

C-shaped support members.

BACKGROUND OF THE INVENTION

There are many working environments where trenches perform a useful function. Often cable is laid in the channel defining the trench. Also, trenches are used to convey water and/or other fluids at commercial and industrial sites. Since a trench is essentially an open cavity in the ground, a cover is necessary to maintain continuity with the surrounding terrain. In most commercial and industrial applications, grates having apertures allowing the passage of fluid therethrough are used to cover the trench.

Trenches are sometimes formed from a moldable composition that hardens to include flat horizontal ledges on opposing sides. Alternatively, a preformed element such as a metal pan having opposed flat horizontal ledges may be installed in the terranean void or ditch to create the trench. The flat horizontal ledges on opposing sides of the trench act as support surfaces for opposed L-shaped angle irons. The horizontal leg of each L-shaped angle iron supports the covering grates which are laid thereon.

Although it is common to allow the grates to lay freely on the angle irons, in some instances it is necessary to secure the grates in place either to satisfy functional requirements or to prevent removal.

In those specific settings, the most common method of

securement is to bolt the grates in place. More specifically, the grates are each formed with a hole for receiving the bolt therethrough. A cross plate attached to and bridging opposed angle irons threadably receives the bolt to thus secure each grate. In this manner, the grates are held against vertical movement.

It can be appreciated, since the bolt may be removed, the bolt-down method is not a fool-proof method of preventing theft or unwanted removal of the grates. In order to ultimately secure a bolted down grate against removal, additional locking methods are required, further increasing the cost and complexity of the assembly. In addition, the cross plate may interfere with the flow of fluid within the trench. If, for instance, solid material is entrained within the fluid, the cross plate may act as a collection point for the solid material. This could eventually lead to blockage of the trench. Accordingly, the need is identified to provide a trench cover assembly that is easy and economical to manufacture and install while providing complete security against cover removal.

SVMWftRY PF THE IPVE HPN

It is a primary object of the present invention to provide a trench cover assembly in which the cover member is completely secure against removal.

It is an additional object of the present invention to provide a trench cover assembly in which the cover member can be secured against removal in conjunction with initial assembly and installation.

It is still another object of the present invention to provide a trench cover assembly having a cover member and a pair of opposed support members

therefor and in which the cover member is held against vertical movement by the support members.

An additional object of the present invention is to provide a trench cover assembly in which the cover member is held against removal along its entire longitudinal length.

It is a further object of the present invention to provide a trench cover assembly that is easy and economical to manufacture and install. Additional objects, advantages and other novel features of the invention will be set forth in part in the description that follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned with the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims. To achieve the foregoing and other objects, and in accordance with the purposes of the present invention as described herein, a trench cover assembly in accordance with the teaching of the present invention is provided. In its broadest sense, the trench cover assembly comprises a cover member and a pair of opposed support members. Furthermore, there is means associated with the support members for holding the cover member against vertical movement, thus securing the cover member against removal. In the preferred embodiment of the invention, the holding means operates along the entire longitudinal length of the cover member. Specifically, the holding means acts against the entire length of cover members along both of the opposed top edges thereof. Furthermore, the cover

member and the support members cooperate to form a flat surface. This aspect of the design is of particular importance in locations where vehicles travel over the trench. Preferably, each of the pair of support members comprises horizontally disposed upper and lower legs bridged by a vertical wall. In order to create the level trench cover for accommodating traffic, the top surfaces of the upper legs are substantially parallel with the top surface of the cover member. In the particular preferred embodiment, the support members are substantially C-shaped in cross-section. In accordance with this design and when in opposed relation, the upper and lower legs of the pair of support members extend inwardly substantially the same distance from the vertical bridging wall. It can be appreciated by those skilled in the art that the upper and lower legs and the vertical wall of the pair of support members thus cooperate to define retaining areas within which the cover member is held against vertical movement.

In an important aspect of the invention, the cover member is formed with a bottom surface and a top surface of reduced lateral dimension relative to the bottom surface. The top surface is defined by rabbets formed in the top outer edge of each of opposing sides of the cover member. This configuration allows the cover member to be received within the retaining areas of the support members so that the top surface of the cover member substantially horizontally aligns with the top surface of the upper legs of the opposed support members.

The opposing support members may be fixed to a pre-formed trench body such as a metal pan. It can be appreciated that the design of the trench cover

assembly is thus sufficiently versatile to allow it to be included as part of a composite preformed trench or to be delivered separately and installed at the work site in association with the pour of a moldable trench composition.

In order to ensure that the cover member is sufficiently secured against removal, each end of the pair of support members is blocked against passage after the cover member has been received therein. This is contemplated as being done using a moldable trench forming composition such as concrete that is poured around the pair of support members when this composition is used to form the trench. Such a composition may also be used at the ends of the preformed trench body to secure the body within a terranean void.

In an alternative design of the trench cover assembly, an upper leg of at least one of the pair of support members is formed with a gap of length greater than the length of the cover member. This is to allow the cover member to pass through the gap to rest on the lower leg of the support member during the installation procedure. In this design, a flat bar of substantially equal thickness to the upper leg of the support member cooperates therewith, as by welding, to fit into and close the gap in the upper leg following placement of the cover member.

In still another alternative design, the trench cover assembly has at least one of the pair of support members that is an angle iron defined by a vertical rail and a horizontal rail. A vertical post is fixably attached to the vertical rail of the angle iron. A horizontal plate is removably attached to the vertical post. When so attached, a portion of the plate extends in overlying relation to a horizontal

rail of the angle iron. Accordingly, with this design, the retaining area of this support member is created and the securing configuration is established following the placement of the cover member therein by attaching the horizontal plate to the vertical post. The invention further contemplates the concept of securing a trench cover assembly in association with a trench. The method comprises providing a cover member and a pair of opposed C- shaped support members. The support members each have a retaining area within which the cover member is cooperatively held. A trench is prepared in a terranean void so as to place the support members in position to receive the cover member. In the preferred inventive method, the cover member is slid into a common accessible end of the pair of support members. This is followed by closing access to both ends of the pair of support members so that the cover member is secured against removal. In the preferred practice of the inventive method, the step of preparing the trench comprises pouring a moldable trench composition into the terranean void and around the pair of support members to fix them in place while allowing free access to at least one common end of each of the pair of support members.

Alternatively, the trench preparing step entails fixing the pair of support members to a preformed trench body and placing the trench body into the terranean void. The method of securing a trench cover assembly in association with a trench can be practiced in other alternative ways. More specifically, as with the preferred practice of the method, a cover member is provided. A pair of opposed support members is also provided, at least one of the pair of support

members having a gap in an upper horizontal leg of length greater than the length of the cover member. A trench is prepared in a terranean void so as to place the support members in position to receive the cover member. The cover member is inserted through the gap in the upper leg of the at least one of the pair of support members so as to rest on its lower horizontal leg. The cover member is placed to be received with the retaining area of the opposed support member. A flat bar is fixedly attached to the at least one of the support members to close the gap therein. In this manner, the cover member is secured against removal.

In a further alternative method, a cover member is also provided. A pair of opposed support members is also provided, each of the pair of support members having a surface on which the cover member is supported. At least one of the pair of support members comprises an angle iron with a vertical post fixedly attached to a vertical rail of the angle iron. The cover member is laid upon the supporting surfaces of the support members. A horizontal plate is attached to the vertical post to extend in overlying relation to the support surface of the angle iron. The cover member is thus secured against removal.

Still other objects of the present invention will become apparent to those skilled in this art from the following description wherein there is shown and described a preferred embodiment of this invention, simply by way of illustration of one of the modes best suited to carry out the invention. As will be realized, the invention is capable of other different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the

drawings and descriptions will be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawing, incorporated in and forming a part of the specification, illustrates several aspects of the present invention and together with the description serves to explain the principles of the invention. In the drawing: Figure 1 is a perspective view of the components of the preferred embodiment of the inventive trench cover assembly;

Figure 2 is an end view of the components of the trench cover assembly shown in Figure 1; Figure 3 is a perspective view of the trench cover assembly shown attached to a preformed trench body;

Figure 4 is a cross-sectional view taken across lines 4-4 of Figure 3; Figures 5a-5e are a series of views showing the method of securing a trench cover assembly in association with a trench;

Figure 6 is perspective view of an alternative embodiment of the trench cover assembly, showing a gap in the upper horizontal leg of one of the support members and a flat bar that is used to fill the gap after placement of the cover member;

Figure 7 is a perspective view of another embodiment of the trench cover assembly, showing an angle iron as one of the support members and the horizontal plate that is cooperatively attached thereto; and

Figure 8 is an enlarged cross-sectional view of the angle iron and horizontal plate shown in Figure 7.

Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawing.

DETAILED DESCRIPTION OF THE INVENTION

A trench cover assembly 10 constructed in accordance with the teachings of the present invention comprises at least one cover member 12 and a pair of opposed support members 14a, 14b. In typical situations, the length of the trench is significantly greater than the conventional length of the cover member 12. Therefore, a plurality of cover members 12 are commonly positioned end-to-end to cover the trench. Although the discussion below refers primarily to the singular, the inventive trench cover assembly may include one or more cover members 12, with each cover member having the same configuration. As will be realized in accordance with the details of the design set out below, the cover member 12 of the assembly 10 is advantageously secured against removal following installation at its operational site.

The inventive design advantageously contemplates the inclusion of means that overlies the cover member 12 to hold it against vertical movement when in place. The preferred design involves associating the holding means with the support members 14a, 14b. In the particular preferred embodiment as shown in Figures 1 and 2, the support members 14a, 14b are substantially c-shaped in cross-section. As is obvious from Figure 2, when in opposed relation, one support member (14a) presents a C-shaped configuration and the other support member (14b) presents an inverted or mirror-image c-shaped configuration. The

use of "C-shaped" as a descriptor is for purposes of simplicity and consistency and refers equally to both ones of the pair of support members 14a and 14b.

With specific reference to the support member corresponding to numeral 14a, each support member is formed with a lower horizontal leg 16a, an upper horizontal leg 18a and a vertical wall 20a that bridges the lower and upper horizontal legs. The legs 16a, 18a and wall 20a define a retaining area 21a within which the cover member 12 is held when the assembly 10 is completed. The opposed support member 14b has identical structure enumerated 16b, 18b, 20b and 21b. Also illustrated as fixed to the support members 14a, 14b are vertically projecting anchor studs 22a, 22b and horizontally projecting anchor studs 24a, 24b. The anchor studs 22, 24 assist in securely fixing the support members 14 when the trench is constructed and do not relate directly on the inventive concept. Those skilled in the art recognize that, in present applications, the conventional trench cover assembly uses angle irons upon which the cover member rests. It can be appreciated that the support members 14a, 14b of the preferred inventive design actually incorporate an angle iron with the addition of the upper horizontal legs 18a, 18b. Accordingly, as is shown in Figure 4, the cover member 12 rests upon the lower horizontal legs 16a, 16b and the vertical walls 20a, 20b substantially prevent the cover member from shifting in a horizontal direction.

In an important aspect of the invention, the upper horizontal legs 18a, 18b overlie a portion of the cover member 12 following assembly. As can be seen from Figures 1 and 3, the overlying relationship occurs along substantially the entire longitudinal

length of the cover member 12. When assembled, the upper horizontal legs 18a, 18b of the support members 14a, 14b prevent the cover member 12 from being lifted away. This prevents the cover member 12 from being removed from the assembly 10.

In most industrial and commercial sites, the cover member 12 in such an assembly takes the form of a grate with drain slots 26 that allows fluid such as rain water to pass through into the underlying trench to be carried away to a storm sewer. While the drawing figures illustrate the use of such a conventional grate as the cover member 12, the inventive trench cover assembly contemplates the use of other types of elements that are conducive to being supported and covering a trench.

A key aspect of the invention involves the particular configuration of the cover member 12 to enable a cooperative fit within the retaining areas 21a, 21b of the support members 14a, 14b. More particularly, the cover member 12 has a substantially flat bottom surface 28 to enable it to rest on the lower horizontal legs 16a, 16b of the support members 14a, 14b. The lateral dimension of the bottom surface 28 defines the overall width dimension of the cover member 12. The particular specifications of each installation site determines the needed width dimension of the cover member 12. It is desirable in all cases, however, to space the opposed support members 14a, 14b at such a distance relative to each other to provide a small amount of clearance between the vertical walls 20a, 20b and the side surfaces 30 of the cover member 12. This is to allow the cover member 12 to slide longitudinally along the support members 14a, 14b during assembly as is described below.

The cover member 12 has a top surface 32 of reduced lateral dimension relative to the bottom surface 28. The relative difference in lateral dimension of the bottom surface 28 and the top surface 32 is created by forming rabbets 34 along the top surface of opposing sides of the cover member 12. The rabbets 34 each form a relief area into which the upper horizontal legs 18a, 18b extend to overlie and hold the cover member 12 against vertical movement. With this design, the primary goal of preventing the removal of the cover member 12 when functionally placed is achieved. As with the clearance between the vertical walls 20a, 20b and the side surfaces 30 of the cover member 12, it is desirable to form the rabbets 34 in such a manner as to allow clearance between the relief surfaces 35a and 35b thereof and the upper horizontal legs 18a, 18b to further allow the cover member to slide within the support members 14a, 14b. As illustrated by the embodiment shown in

Figure 4, it is also preferable to design the inventive cover assembly 10 so that the top surface 32 of the cover member 12 is substantially horizontally aligned with the top surfaces 36a, 36b of the upper horizontal legs 18a, 18b of the support members 14a, 14b. This allows the presentation of a substantially flat surface across the entire extent of the trench cover assembly 12. This design is of particular importance at commercial and industrial sites where substantial vehicle traffic takes place. The continuous level surface eliminates jarring of the vehicle since the wheels thereof roll along a constant plane.

The inventive trench cover assembly 10 is adapted for use with trenches formed in accordance

with the teachings of the applicant's patented method disclosed in U.S. Patent 5,281,051, issued January 25, 1994, entitled TRENCH FORMING ASSEMBLY AND METHOD, the content of which is incorporated herein by reference. The trench cover assembly 10 is also contemplated as being fixed to preformed trench bodies that have long been used in the art.

Figures 3 and 4 illustrate a typical preformed trench body with which the trench cover assembly 10 is adapted to be used. More particularly, a metal pan 38 is shown fixed to the lower horizontal legs 16a, 16b through welds 40a, 40b. As is common, the pan 38 includes locking ribs 42 on opposed sides thereof to assist in securing the pan in its surrounding environment. By fixing the support members 14, 14b to the preformed trench body prior to functional placement, aligned positioning of the trench cover assembly 10 over the trench is assured.

The inventive method of securing a trench cover assembly 10 over a trench is illustrated in the series of Figures 5a-5e. The trench in this series of figures may be formed in accordance with the teaching of U.S. Patent 5,281,051 cited above using a moldable trench composition such as concrete. Beginning with Figure 5a, the components of the trench cover assembly 10, including the cover member 12 and support members 14a, 14b, are provided at the installation site. A terranean void or ditch 44 is dug in the ground 46. In this illustrated embodiment of the method, a trench form 48 is placed in the ditch 44 in preparation for receiving a moldable trench composition 50, such as concrete, therearound.

Figure 5b illustrates the trench composition 50 surrounding the form 48. The composition 50

hardens around the form 48 as it dries and, after the form is removed, the hardened composition defines the body of the trench 51 (see Figure 5c) . It can be appreciated by comparing Figures 5a and 5b that the anchor studs 22 and 24 have been enveloped by the hardened trench composition 50 to thus provide reinforcement for stable positioning of the support members 14a, 14b within the trench.

After the trench form 48 has been removed, the support members 14a, 14b are ready to receive the cover member 12. At least one common end of each of the support members 14a, 14b are allowed to remain accessible following the pour of the moldable trench composition 50 around the trench form 48. As shown in Figure 5c, the cover member or members 12 are slid into the accessible end of the support members 14a, 14b in accordance with direction arrow A. It can be appreciated that both ends of the support members 14a, 14b may be allowed to remain accessible when a trench 51 of significant length is being constructed. The cooperative receipt of the opposed rabbets 34 of the cover member 12 within the retaining areas 21a, 21b allows this assembly step to be accomplished.

Once all cover members 12 to be used are in place, the ends of the support members 14a, 14b are closed. This involves filling the balance of the terranean void 44 with trench composition 50 as shown in Figure 5d to block the ends of the support members 14a, 14b. The cover members 12 are thus secure against removal and present a level surface in combination with the support members 14a, 14b to allow smooth travel thereover (see Figure 5e) .

An alternative embodiment of the trench cover assembly 10 is shown in Figure 6. In this embodiment, the support member 14b is shown with a gap

52 in the upper horizontal leg 18b. The gap 52 has a dimension that is greater than the dimension of the longitudinal length of each of the cover members 12. This allows the cover members 12 to be passed through the gap to rest on the lower horizontal leg 16b and be manipulated to comfortably fit within the retaining area 21a of the opposed support member 14a. Once all of cover members 12 are in their proper position, a flat bar 54 of length equal to the gap 52 is directed thereto (note arrow B) and is fixed in place, preferably by welding. The flat bar 54 is also of a thickness substantially equal to the thickness of the upper horizontal leg 18b. The size consistency of the retaining area 21b is thus preserved upon attachment of the bar 54 to the leg 18b. The gap 52 is thus eliminated following attachment and the cover members

12 are held against removal at the operational site.

Although Figure 6 illustrates a gap 52 only in support member 14b, the inventive assembly 10 contemplates a like gap in the opposed support member 14a. Regardless of whether a gap 52 exists in either one or both of the support members 14a, 14b, the filling of the gap(s) by the flat bar(s) 54 creates in essence C-shaped support members 14a, 14b having retaining areas 21a, 21b for holding the cover members 12 against vertical movement.

A further alternative embodiment of the trench cover assembly 10 is illustrated in Figures 7 and 8. The support member 14b in this embodiment is formed as an angle iron 56. The angle iron 56 has a vertical rail 58 and a horizontal rail 60. The horizontal rail 60 supports the cover member 12 laying thereon. At least one vertical post 62 is fixed to the vertical rail 58 of the angle iron 56. Each

vertical post 62 has a threaded orifice 64 adapted to receive a bolt 66.

In order to create the holding means in this embodiment, a horizontal plate 68 cooperatively attaches to the angle iron 56. The horizontal plate 68 is formed with at least one hole 70 through which the bolt 66 extends. When the horizontal plate 68 is bolted to the angle iron 56, a portion of the plate forms an upper horizontal leg that overlies the area above the horizontal rail 60 and ultimately, the cover member 12.

Figure 7 depicts the horizontal plate 68 as having three spaced holes 70 that, when positioned for assembly, align with three vertical posts 62 on the vertical rail 58 of the angle iron 56. This is for illustration purposes only and a greater or lesser number of holes 70 and the resulting spacing thereof may be used.

When this embodiment is in use, the trench 51 is formed in the same manner as described above. When the cover members 12 are ready to be put in place, they are laid upon the horizontal rail 60 of the angle iron 56 and manipulated so as to comfortably fit within the retaining area 21a of the opposed support member 14a. The horizontal plate 68 is properly aligned with the angle iron 56 and bolts 66 are inserted through the holes 70 and threaded into the orifices 64 of the posts 62. Since the horizonal plate 70 overlies the horizontal rail 60 and thus the cover members 12, the cover members cannot be lifted from their position within the support members 14a, 14b.

Those skilled in the art can recognize that both support members 14a, 14b can be formed as angle irons to be used with cooperating horizontal plates.

As with the other embodiments, when in final assembly, the vertical rail 58, the horizontal 60 and the overlying portion of the horizontal plate 68 define a C-shaped support member (14a and/or 14b) with a retaining area (21a and/or 21b) within which the cover member 12 is confined.

It is recognized that the embodiment of the inventive trench cover assembly 10 just described differs from the other embodiments in that the cover member 12 is releasably restrained within the support members 14a, 14b following assembly and functional placement. Nevertheless, this particular design provides advantages over prior art models in that it involves fewer components and less material that require an element that extends between the support members and may interfere with the flow of fluid within the trench.

In summary, numerous benefits derive from employing the inventive trench cover assembly 10 and the method securing such an assembly in association with a trench. The C-shaped support members 14a, 14b presented in the functional environment hold the cover member 12 against removal without the use of elements that may interfere with the flow of fluid within the trench 51. The formation of rabbets 34 on the top outer edges of the cover member 12 allows its cooperating receipt within the support members 14a, 14b and the capability of sliding for entry and/or positioning. The design of the trench cover assembly 10 also presents a level surface over which vehicles may smoothly travel.

The foregoing description of a preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to

the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as is suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.