Sliding clip with extended travel

An improved sliding clip for a standing seam roof, the clip having a clip base supporting a clip tab adapted to connect to a standing seam, the clip tab slidably supported by the clip base along a slide track on the clip base, the clip tab permitted to travel a selected range along substantially the full length of the clip base so that the length of the travel path can exceed or be less than the length of the clip base. Stop members on the clip base and clip tab are positioned to abut when the clip tab is moved in either direction along the slide track. Alternate tab stops can be provided to selectively determine the extent of travel of the clip tab along the travel path.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to the field of metal buildings, and more particularly but not by way of limitation, to sliding clips of expanded travel range to accommodate environmental temperature variations on standing seam metal roof assemblies.

Standing seam metal roofs are formed from interconnected panels supported by underlying support structures, which are usually purlins or joists that are supported by column members extending upwardly from the building foundation. Standing seams are formed at the interconnected edges of the roof panels.

The established practice in the metal building industry has been to provide hold-down clips that connect to the roof panels at the standing seams and are affixed to the underlying purlins or joists. The standing seams of the panels are usually sealed to eliminate or minimize the invasion of moisture from the environment through the standing seams into the protected building interior. Such sealing is difficult to achieve, and is made even more difficult by the expansion and contraction of the roof panels with environmental temperature variations to which the roof is subjected.

In anticipation of the movement of the roof panels with temperature variations, floating clips, also referred to as sliding clips, are utilized to provide a sliding connection between a hold-down clip portion, referred to as the clip tab, and a base portion of the clips, with the clip tabs connected to the standing seams and the base portions secured to the underlying support structure.

Even with the use of floating or sliding clips, the problem of roof panel creep with temperature variations has not been totally solved, largely because prior art sliding clips have not provided sufficient clip travel to accommodate the full range of panel expansion and contraction experienced over the large temperature ranges encountered by large standing seam roof assemblies. For one thing, the more that panel travel is allowed for in a clip design, the greater must be the length of either the clip tab or the supporting clip base, and greater length clip design results in higher costs.

U.S. Pat. No. 4,575,983 teaches proportioning the travel distance of a roof assembly by means of a sliding clip such that a greater amount of panel travel in one direction is permitted, while accommodating less panel travel movement in the opposite direction. However, this patent does not deal with accommodating a greater total panel travel for a given clip.

Generally, floating clips in the past have allowed equal amounts of movement for expansion and contraction, the movement of the hold-down portion relative to the clip base portion being limited by stops on the clip base. Such stops are necessary to keep the upper clip tabs and the lower clip bases together. Responsive to ambient or internal temperature changes, the interconnected metal panels expand and contract, and the floating clips allow for such dimensional changes and for panel travel. However, the range of clip travel (the travel of the sliding clip tab) is contained within the total length of the clip base or of the clip tab.

Although obvious to the most casual observer, one thing is generally overlooked, and that is: the frame, purlins and panels of a pre-engineered building are generally erected at substantially the same temperature. This occurs because the building components are erected before the heating and cooling equipment is installed. Normally, a layer of insulation is placed between the purlins and the panels, and it is only following this installation that substantial differential expansion and contraction occurs between the roof or wall panels and the underlying support structure.

Certain information is required to accurately predict the relative movement that a sliding clip will encounter in service. These include, 1) the temperature to which the building components will be subjected during erection of the building; 2) the maximum and minimum temperatures to which the building interior will be subjected during the life of the building; and 3) the maximum and minimum temperatures to be encountered by the building components during the life of the building. It will be appreciated that these information items are extremely difficult, if not impossible, to foreknow, and it behooves the clips to accommodate maximum clip movement from a neutral point.

Therefore, in selecting a clip for a particular building to be constructed, it is clear that, not only must the selected clip and its attachments to the panel and to the underlying support structure be adequate, the clip tab must also be capable of sliding at a force less than that required to slide the clip tab in the panel seam. If the force to effect movement of the clip tabs relative to their bases is greater than the force to cause the clip tabs to slide in the panel seams, the resultant movement of the clip tabs in the seams will degrade the seam sealant and increase the probability that the panel seams will leak.

It is clear that there is a need for floating clips for standing seam roof assemblies that will permit the maximum amount of expansion and contraction travel of the panels with temperature changes, while also minimizing the clip dimensions and reducing costs.

SUMMARY OF INVENTION

A floating clip for a standing seam roof, the standing seam roof having roof panels interconnected by a standing seam, the sliding clip having a clip base and a clip tab, the clip tab having an upper portion that is configured to engage the standing seam of the standing seam roof. The clip tab is connected to the clip base for relative sliding movement between it and the clip base along a travel path. Pairs of interfering base stops, supported by the clip base, and tab stops, supported by the clip tab, determine the length of the relative travel between the clip tab and clip tab, the total such travel distance being up to substantially the sum of the lengths of the clip base and the clip tab.

That is, the improved sliding clip of the present invention provides a clip tab that adapted to be slidably supported by a clip base for sliding along a travel path the length of which being a selected range along the full length of the clip base so that the length of the travel path can be greater than the greater of the length of either the clip base or the clip tab. Stop members on the clip base and on the clip tab are positioned to abut when the clip tab is moved in either one direction along the travel path. Alternate tang tab stop members can be provided and left in an inoperative mode during manufacture to be selectively activated or made operative as required at and installation site.

The features and advantages of the present invention will become apparent from the following description of the preferred embodiments and claims when read in conjunction with the drawings.

DESCRIPTION

Fixed and floating clips are integral parts of most metal panel roofs with runs over about 40 or 50 feet in length. Fixed and floating clips are used in various combinations to attach the metal roof panels to the underlying structure without creating excessive stress or strain in the structure with the occurrence of differential movement (expansion and contraction) between the panels and the support structure. Such differential movement is especially in play once insulation has been installed between the metal panels and the underlying support structure.

The longer the panel run, or the greater the differential temperature, the greater the slide distance required between the clip tabs and the clip bases. Thus, it is desirable to have floating clips with greater slide capability to accommodate these forces without sacrificing other desirable characteristics, such as ease of erection and use, and also without sacrificing low cost.

Floating clips have spaced apart stops between which the clip tabs travel, the stops preventing separation of the clip tabs from their clip bases, as well as separation of the clip tabs (and thus the standing seams) from the underlying support structure. In general, past practice in designing floating clips has been to provide for equal movement of the clip tab along the clip base in both directions from the center of the clip base.

FIGS. 1 and 2illustrate a typical prior art floating clip for a standing seam roof. Shown therein is a floating clip10, and for purposes of illustration, the side of the floating clip10having a male hold down side12, and an opposing side13. It will be noted that the floating clip10is generally symmetrical about a vertical, center axis14.

The floating clip10has a clip base16, and the vertical axis14represents the center thereof. The clip base16is attached to an underlying support member18via self tapping screws (not shown), the underlying support structure18usually being a purlin or joist of a building under construction. A clip tab20is interconnected at its lower end via overlapping edges configured to form a sliding track22for the clip base16.

The floating clip10has an upper hook portion24extending from the clip tab20and configured to attach over the male portion of a standing seam (not shown) of the metal panels of the standing seam roof. A range of permitted relative movement between the clip base16and the clip tab20, along the sliding track22, is desired when the panels and underlying support structure18are subjected to differential expansion/contraction as a result of environmental conditions. This relative movement is achieved by the sliding movement of the clip tab20on the clip base16.

The elements of the clip base16and the clip tab20that serve to limit the sliding path of clip base16/clip tab20are: a first or right tab stop26and a second or left tab stop27; and a first or right base stop28on one edge of the clip base16and a second or left base stop29on the opposing edge of the clip base16.

Dual interfering stop pairs are provided to determine the length of relative travel between the base16and the clip tab20, as follows: the right tab stop26and the right base stop28form a first or right interfering stop pair30, and the left tab stop27and the left base stop29form a second or left interfering stop pair31. As used herein for convenience of reference, the terms “right” and “left” are the reader's right and left as the reader viewsFIG. 2.

Starting from when the base16is centered relative to the center axis14(as depicted inFIG. 2), the right interfering stop pair30(the right tab stop26and the right base stop28) determine a right travel distance32that the clip tab20can travel to the right, and the left interfering stop pair31(the left tab stop27and the left base stop29) determine a left travel distance33that the clip tab20can travel to the left, relative to the clip base16. With the distance between the right and left tab stops30,31being a clip slide path34, the clip base16having a clip base length35, and the clip tab20having a clip tab length36, the total travel of the clip tab20relative to the base16is the length of the clip side path34minus the clip base length35, the total travel being substantially less than the total clip tab length36. In the prior art clip10, the amount of relative travel of the clip tab20on the base16is the difference between the length of clip slide path34less the base length35, and the total travel is confined within, and is less than, the clip tab length36.

Another prior art floating clip10A is shown inFIGS. 3 and 4, the floating clip10A having a clip base16A that is longer than its clip tab20A, which is slidingly supported on the clip base16A via a slide track22A. The clip tab20A has a clip tang or protrusion37that is cut from, and is bent to extend from, the clip tab20A substantially perpendicularly to side13A. The clip tang37serves to restrain the clip tab20A between right and left base stops26A and27A that are elements of the base16A. A clip slide path34A is defined between the inner edges of the base stops26A and27A.

Since the relative travel is determined by a dual pair of interfering stop pairs in the same manner as described for the floating clip10, and the outer and inner stops are comparative, similar numbers with an added suffix letter will be used to designate the operative stops. A first or right base stop26A and a first or right tab stop28A (one edge of the tang37) form a first or right interfering stop pair30A; and a second or left base stop27A and a second or left tab stop29A (the opposing edge of the tang37) form a second or left interfering stop pair31A. As above, the terms “right” and “left” are the reader's right and left as the reader viewsFIG. 3.

Starting from when the base16A is centered relative to the center axis14A of the clip tab20A, the right interfering stop pair30A (the right base stop26A and the right tab stop28A) determine the right travel distance32A that the clip tab20can travel to the right, and the left interfering stop pair31A (the left base stop27A and the left tab stop29A) determine the left travel distance33A that the clip tab20A can travel to the left, relative to the clip base16A. With the distance between the right, left base stops26A,27A, respectively, being the length of the clip slide path34A, the clip tang37having a clip tang length35A (along the slide track22A), and the base16A having a clip base length36A, the total travel of the clip tab20A relative to the base16A is the length of the clip slide path34A minus the clip tang length35A, the total travel being substantially less than the clip base length36A. In the prior art clip10A, the amount of relative travel of the clip tab20A on the base16A is the difference between the slide path length34A minus the tang length35A, and this total travel is confined within, and is less than, the base length36A.

In past practice, clip tabs were generally erected in such a manner that the clip tab was temporarily held in a neutral position while the clip was being attached to the underlying structure. Only after installation was the clip tab free of restraint and able to move in either of two directions as required by the forces of panel expansion and contraction. The coordinated slide stops that define clip slide travel extended wholly from the hold down side or on the opposite side of the clip, but not from both sides. The clip base in past clips has usually been located at the clip centerline to provide equal clip slide travel in both directions.

In the prior art clip10ofFIGS. 1 and 2, clip slide travel is limited by the slide stops26,27located on the clip tab20, and by one or more coordinated elements located on the clip base16, thereby permitting clip tab travel between the stops26,27. The floating clip10A ofFIGS. 3 and 4has the slide stops26A,27located on the clip base16A, and the coordinated clip tang37extends from the clip tab20A to prevent travel past the base slide stops26A,27A. The length of slide travel of the clip tab20A is the length of the clip slide path34A minus clip tang length35A.

For both the floating clip10ofFIGS. 1-2and the floating clip10A ofFIGS. 3-4, clip slide in either direction is limited to less than half the length of the clip slide path32or32A, and in each of these clips, the total slide is less than the total length of the supporting clip base.

FIGS. 5,5A and5B show a floating clip40that is constructed in accordance with the present invention. As discussed above, it is desirable that a floating clip achieve maximum slide travel along the base clip without allowing such slide travel to cause the clip tab to disengage, slide off the clip base or fail under uplift forces, and yet accommodate longer panel runs without creating stress and strain in the structure. The floating clip40ofFIG. 5utilizes a non-symmetrical slide configuration wherein portions of the right and left clip edges overlap the ends of the clip base at points along the slide path to achieve much greater slide travel than heretofore provided.

InFIG. 5, a view of clip40from side42, the clip40has a clip tab44with a lower edge forming a slide track46. A first or right tang or protrusion forms a right tab stop48, and a second or left tang or protrusion forms a left tab stop50, cut and extending from, the clip tab46and located at different heights above a clip base52that is connected to the clip tab44via the slide track46. The clip base52has a first or right base stop54and a second or left base stop56extending upwardly and configured individually with different shapes.

The right base stop54is shaped differently from the left base stop56, the right base stop54extending upwardly substantially parallel to the clip tab44. The right base stop54is configured to have a clearance gap58positioned to allow the right tab stop48to clear the right base stop54as the clip tab44moves in a first or right direction60and yet extends to a sufficient height so that the left tab stop50strikes the right base stop54after the right tab stop48has passed through the clearance gap58to clear past the right base stop54. The left base stop56is configured in a shape that allows the left tab stop50to clear the left base56as the clip tab44moves in a second or left direction62and yet is configured so that the right tab stop48strikes the left base stop56after the left tab stop50has cleared the left base stop56.

The right and left base stops54,56, together with the right and left tab stops48,50, cooperate to form dual interfering stop pairs to establish the length of relative travel between the base16and the clip tab20, as follows: a first or right interfering stop pair64(the right base stop54and the left tab stop50); and second or left interfering stop pair66(the left base stop56and the right tab stop48). As the terms “right” and “left” are used for convenience of reference, and refer to the reader's right and left, respectively, consistent with the right and left directions60,62.

The slide travel distance can be selectively determined by altering distances L1(the distance between the right base stop54and the left tab stop50, which are the right interfering stop pair64) and L2(the distance between the left base stop56and the right tab stop48, which are the left interfering stop pair66), as measured when the clip tab44is centered on the clip base52.

FIG. 5Ais a partial sectional view through clip40at section5A.FIG. 5Bis a partial sectional view at section5B of the clip40after clip tab44has moved in the direction62until the right tab stop48has come into contact with the left base stop56, with the left tab stop50and the right base stop54omitted for clarity.

A first tang or protrusion, to form an alternate right tab stop48A, and a second tang or protrusion, to form an alternate left tab stop50A, are depicted by broken lines inFIG. 5to demonstrate the ease of varying the slide travel lengths in both direction60and direction62. Clip travel in direction60can be increased by forcing the right tab stop48to an inoperative position, thereby causing the alternate right tab stop48A to take its place as the slide travel stop on that end of the clip40. This can be performed during manufacturing or during erection of the roof.

During manufacture, one or both of the right tab stops48,48A can simply be left out of the clip tab44and formed at the installation site. Alternatively, both right tab stops48and48A can be formed, but not made operative, that is not bent to extend, during manufacture, and at the installation site, one of the protrusions48,48A can be bent to extend from the clip tab44to make it operative as appropriate to the need of the application.

In like manner, clip travel in direction62can be increased by forcing the left tab stop50to an inoperative position, thereby causing the alternate tab stop50A to take its place as the slide travel stop on that end of the clip40. This can also be performed during manufacturing or during erection of the roof. During manufacture, one or both of the left tab stops50,50A can simply be formed but not bent to extend, and the desired one of these bent at the installation site.

Alternatively, both of the left tab stops50,50A can be formed but not bent during manufacture, and at the installation site, one of the left tab stops50,50A can be folded to extend during the erection process. And as stated herein above, the slide travel in either direction can be selectively determined and/or altered by changing the distance L3(between the left base stop56and the right tab stop48A) and/or distance L4(between the right base stop54and the left tab stop50A).

While only one pair of alternate right and left tab stops48A,50A are shown formed in the clip tab44of the clip40, it will be appreciated any number of such tab stops can be formed during manufacture, and once the clips are at the installation site, workmen can select and bend such tab stops as may be applicable for a particular installation and desired length of the travel path for the relative movement of the clip tab44to the clip base52.

FIGS. 6,6A and6B show a floating clip70also constructed in accordance with the present invention wherein the clip slide asymmetry is similar to that of the clip40, so like numbers are used to designate like elements. However, the length of clip base72exceeds the length of clip tab74. It is desirable in some situations to vary the relation of the clip tab74and base72to optimize the clip for such factors as strength and cost. As above, the travel distance between the base stops and the tab stops, such as L5, (the distance between the left base stop56and the right tab stop48) can be established as required for any particular field application.

FIGS. 7,7A,7B and7C are views of another floating clip80constructed in accordance with the present invention in which the asymmetry relating to the slide/stop mechanism occurs on opposite sides of the clip80when viewed from its end. That is, one set of corresponding base stops and tab stops is on side82, and one set is on side84of the clip80.

The clip80has a clip base86and a sliding clip tab88. For convenience of reference and clarity, like numbers will be used where applicable in the description of the clip80as those used for the clip40. Thus, the clip80has a first tab stop48and a second tab stop50, each extending from opposing sides82,84, respectively, and the clip80has a first base stop54and a second base stop56, each supported by the clip base86on opposing sides84,82, respectively, of the clip80.

The first tab stop48, extending from side82of clip tab88, cooperates with the second base stop56formed on the clip base86to act as one pair of interfering stop elements to limit the slide travel of clip tab88in one direction62. The second tab stop50, extending from side84of clip tab88, and the first base stop54formed on the clip base86act as another pair of interfering stop elements to limit the slide travel of the clip tab88in the opposite direction60. A panel support member90is formed on the clip base86for the purpose of supporting a panel corrugation (not shown) of the standing seam roof panel to which the floating clip80is attached.

The clip tab88can slide the distance denoted as length L1(inFIG. 7, the distance between the second base stop56and the first tab stop48) in direction62, or it can slide the distance denoted as length L2(inFIG. 7A, the distance between the first base stop54and the second tab stop50) in direction60. It should be noted that the total travel distance (L1and L2) is greater than the length of either the clip tab88or the clip base86separately. This clip slide travel far exceeds that of previous clips, the slide travel of which is limited to less than half of the longest of the clip tab or the clip base.

While a single pair of right and left tab stops48,50are shown inFIGS. 7 through 7B, it will be appreciated that the clip tab74also can be provided with a plurality of alternate tab stops formed during manufacture but left in an inoperative state until the clips are received at an installation site. Once the clips are at the installation site, workmen can select and bend such tab stops as may be applicable for a particular installation and desired length of the travel path for the relative movement of the clip tab74to the clip base72.

The present invention will now be described with reference toFIGS. 8 through 8C, which are views of yet another floating clip100constructed in accordance with the present invention in which the asymmetry relating to the slide/stop mechanism occurs on opposite sides of the clip100. That is, the clip100has a clip base102and a sliding clip tab104, and one set of corresponding base stops and tab stops is on side106of the clip tab104, and one set is on the other side108thereof.

For convenience of reference and clarity, like numbers will be used where applicable in the description of the clip100for the embodiments described herein above, such as the clip80. Thus, the clip100has a first tab stop48and a second tab stop50, each extending from opposing sides106,108, respectively, and the clip100has a first base stop54and a second base stop56, each supported by the clip base102on opposing sides106,108, respectively, of the clip100.

The clip tab104and the clip base102are interconnected by a rolled slide track110that permits relative sliding movement of the clip tab104and the clip base102, while holding the clip tab104and the clip base102in close alignment. The clip tab104has an upper hook portion112that is configured to attach over, and engage with, a standing seam of interconnected adjacent roof panels (not shown).

The first tab stop48, extending from side106of clip tab104, cooperates with the second base stop56formed on the clip base102to act as one pair of interfering stop elements to limit the slide travel of clip tab104in one direction62.

The second tab stop50, extending from side108of clip tab104, and the first base stop54formed on the clip base102act as another pair of interfering stop elements to limit the slide travel of the clip tab104in the opposite direction60.

The clip tab104can slide the distance denoted as length L1(the distance between the second base stop56and the first tab stop48) in direction62, or the clip tab104can slide the distance denoted as length L2(the distance between the first base stop54and the second tab stop50) in direction6o. The total travel distance (L1and L2) of the clip tab104is greater than the length of either the clip tab104itself or the clip base102separately. Thus, the slide travel of the clip tab104of the clip100far exceeds that of any previous clip, since the total movement accommodated by prior art floating clips has been limited to less than half of the longest of the clip tab or the clip base.

The clip base102is provided with several attachment holes114to secure the clip100to a purlin understructure via fasteners (not shown) extending there through. When installed with the clip tab104attached to a standing seam of interconnected roof panels (not shown), as pointed out above, the length of slide travel provided by the clip100is substantially equal to the sum of the lengths of the clip tab and clip base (such clip movement diminished only by the dimensions of the inner, or inboard, stop members), thereby far exceeding that provided by prior art sliding clips.

While a single pair of right and left tab stops48,50are shown inFIGS. 8 through 8C, it will be appreciated that the clip tab104also can be provided with a plurality of alternate tab stops formed during manufacture but left in an inoperative state until the clips are received at an installation site. Once the clips are at the installation site, workmen can select and bend such tab stops as may be applicable for a particular installation and desired length of the travel path for the relative movement of the clip tab104on the clip base102.

It is clear that the present invention is well adapted to carry out its objects and to attain the ends and advantages mentioned as well as those inherent therein. While presently preferred embodiments of the invention have been described in varying detail for purposes of the disclosure, it will be understood that numerous changes may be made which will readily suggest themselves to those skilled in the art and which are encompassed within the spirit of the invention disclosed and as defined in the above text and in the accompanying drawings.