This invention relates generally to a portable roadway warning device comprising any desired number of portable modular rumble strips for use in various roadway conditions to alert drivers of automotive vehicles including both passenger vehicles and trucks of an approaching condition.

BACKGROUND OF THE INVENTION

It is generally known to use rumble strips in roadway applications to provide a perceptible noise and warning vibration when automotive vehicles including passenger vehicles and trucks drive over the rumble strips to warn the drivers of an approaching condition such as a work site, construction site, slow speed zone, checkpoint, tollbooth and so on, without alarming the drivers and without adversely affecting the stability of the vehicles. Some types of rumble strips are intended to be permanently installed for long-term use while others are intended to be portable for use at work zones and other applications of relatively short duration. Portable rumble strips should be reusable and quick and easy to deploy and remove. Also they should have the ability to remain in place under heavy traffic conditions.

SUMMARY OF THE INVENTION

The above and other benefits and advantages of portable rumble strips are accomplished in accordance with the present invention by providing one or more modular rumble strips each comprised of two or more modular strip sections each having a substantially greater length than width, and top and bottom surfaces and end and side edges, and each fabricated of a suitable flexible polymeric material such as rubber or polyurethane or other polymeric material with similar properties.

In accordance with one aspect of the invention, each rumble strip comprises at least two modular strip sections each having a plurality of aligned alternating notches and tabs at at least one of the end edges of each of the strip sections, and connecting links hingedly connecting the tabs at one of the end edges of one of the strip sections to respective aligned tabs at another of the end edges of another strip section.

In accordance with another aspect, the tabs at the respective end edges of each of the strip sections have aligned lateral through holes axially inwardly spaced from the respective end edges, and each of the connecting links comprises two laterally spaced rods extending through the respective through holes in the aligned tabs at the one and the another end edges of the one and the another strip sections, and a pair of link plates attached to respective opposite ends of the two rods to maintain a desired lateral spacing between the two rods that is slightly greater than the spacing between the through holes in the respective aligned tabs when the one and the another end edges of the one and the another strip sections are in parallel alignment with one another.

In accordance with another aspect of the invention, the notches adjacent opposite side edges of the respective tabs have a depth greater than the length of the end portions of the link plates extending radially outwardly beyond the respective rods to allow for folding of the interconnected strip sections in overlying relation to one another. BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a top plan view of one form of modular strip section of the present invention.

Fig. 2 is an enlarged fragmentary longitudinal section through a portion of the strip section of Fig. 1 , taken on the plane of the line 2-2 thereof.

Fig. 3 is a perspective top view of a modular rumble strip of the present invention comprising two of the strip sections of Fig. 1 hingedly connected together in end to end relation to one another.

Fig. 4 is an enlarged fragmentary top perspective view of the encircled area A of the hingedly connected end edges of the two strip sections of Fig. 3.

Fig. 5 is a further enlarged fragmentary longitudinal section through the hingedly connected end edges of the two strip sections of Fig. 4, taken on the plane of the line 5-5 thereof. Fig. 6 is a perspective top view of the modular rumble strip of Fig. 3 but showing the two hingedly connected strip sections folded in overlying relation to one another.

Fig. 7 is an enlarged fragmentary top perspective view of the encircled area B of the hingedly connected end edges of the two strip sections of Fig. 6 folded in overlying relation to one another.

Fig. 8 is a further enlarged fragmentary longitudinal section through the hingedly connected end edges of the two folded over strip sections of Fig. 7, taken on the plane of the line 8-8 thereof.

Fig. 9 is an enlarged top perspective view of a portion of the hingedly connected end edges of the two folded over strip sections of Fig. 7.

DETAILED DESCRIPTION

Referring now more particularly to the drawings, wherein the same reference numbers are used to designate like parts, and initially to Figs. 1 and 2, there is shown one form of a modular strip section 1 of the present invention which may be hingedly connected to one or more other modular strip sections as described hereafter to form a portable modular rumble strip for use in various roadway conditions to alert drivers of automotive vehicles including both passenger vehicles and trucks of an approaching condition such as a work site, construction site, slow speed zone, checkpoint, tollbooth and so on. Each strip section 1 desirably has substantially flat top and bottom surfaces 2 and 3 and opposite side edges 4 and 5 and end edges 6 and 7. Also each strip section is desirably made of a suitable high strength, weather-resistant polymeric material such as rubber or polyurethane or other polymeric material with similar properties. Suitable hand grip slots 10 may be provided in each rumble strip section adjacent one or both ends for ease of picking the rumble strip sections up.

Although the dimensions of each rumble strip section 1 may vary, each rumble strip section has a width that is preferably between approximately eight inches and approximately sixteen inches and more preferably of approximately thirteen inches. Also each rumble strip section is of sufficient thickness to create a noticeable audible and vibration warning to drivers of automotive vehicles including trucks and passenger vehicles when driven over the rumble strip sections, but not so severe as to alarm the drivers, and without adversely affecting the stability of the vehicles. To that end, each rumble strip section preferably has a thickness of between approximately one-half inch and approximately one inch and more preferably of approximately three-quarter inch.

To provide a better grip between the bottom surface 3 of the rumble strip sections 1 and the roadway and to reduce possible skidding of vehicle tires against the top surface 2 of the rumble strip sections when wet, both the top and bottom surfaces 2 and 3 of the rumble strip sections may have texturing 15 and 16. Also the texturing may be in the form of an open diamond pattern as schematically shown, for example, in Figs. 4 and 7, to provide a channel effect to permit the escape of water from both underneath and above the strip sections.

The leading side edge 4 or 5 of each rumble strip section that faces oncoming vehicle traffic or both side edges 4 and 5 of each rumble strip section may be beveled to help eliminate any possible movement of the rumble strips caused by initial contact of the vehicle tires with the rumble strips. The included angle of the beveled leading side edge 4 or 5 or both side edges 4 and 5 of the rumble strip sections is preferably between approximately 10° and approximately 15° and more preferably approximately 12°.

As seen for example in Fig. 1 , each strip section 1 has aligned alternating tabs 20 and notches 21 , 21 ' and/or 21 " in opposite end edges 6 and 7 for connecting the end edges of two or more strip sections together to form a rumble strip of any desired length as described hereafter.

In one form of the invention, each of the individual strip sections 1 preferably has a length of between approximately five feet and approximately six feet and more preferably approximately five and one-half feet, whereby a rumble strip 26 comprised of two strip sections 1 hingedly connected together in end to end relation as shown in Fig. 3 will be of sufficient length to reach across a single highway lane, which is typically approximately eleven feet wide. Each of the individual strip sections 1 may be somewhat longer or shorter than that or of different lengths if desired. Also more than two modular strip sections may be used to make up a single rumble strip if desired. However, a single rumble strip comprised of two modular strip sections hingedly joined together as described hereafter, each having a length of approximately five and one-half feet, can easily be folded in half with the folded strip sections in overlying relation to one another with their top surfaces facing each other, can easily be fitted in the bed of a pickup truck for easy transport and deployment. This makes the rumble strips particularly easy to deploy and remove and reuse for work zones of relatively short duration.

If each rumble strip 26 comprised of two (or more) strip sections 1 hingedly connected together is found not to be heavy enough to remain in place under heavy traffic, a plurality of laterally spaced, transversely extending metal plates or bars 28, preferably made of steel or cast iron, may be embedded within the approximate center of the thickness of each rumble strip section as schematically shown in Fig. 2 to provide the necessary ballast to keep each rumble strip in place without having to use any adhesive or fasteners. Alternatively, the plates or bars may be partially embedded in the strip sections, or cavities may be provided in the strip sections to accept the plates or bars, or the plates or bars may be mechanically fastened or adhesively affixed to the top surfaces of the strip sections if desired. The metal plates or bars 28 preferably run transversely across the width of the strip sections to provide stiffness in the transverse direction so the side edges of the strip sections don't curl in use, and are desirably embedded the approximate center of the thickness of each strip section.

The number and combined weight of the individual plates or bars 28 embedded in the strip sections 1 should be sufficient to cause the rumble strips to stay in place under heavy traffic, but not make the rumble strips so heavy they cannot easily be folded in half and moved by two persons. For example, the overall weight of each strip section that is approximately five and one-half feet in length may be between approximately fifty pounds and approximately sixty pounds and more preferably approximately fifty-five pounds, whereby the overall weight of a rumble strip comprised of two strip sections hingedly connected that are each approximately five and one-half feet in length will be between

approximately one hundred pounds and approximately one hundred twenty pounds and more preferably approximately one hundred ten pounds. As seen for example in Figs. 4 and 5, the tabs 20 at the respective end edges 6 and 7 of each of the strip sections 1 have aligned lateral through holes 30 axially inwardly spaced from their respective end edges to facilitate hingedly connecting the tabs 20 at one of the end edges 6 of one of the strip sections to respective aligned tabs 20 at another of the end edges 7 of another of the strip sections using suitable connecting links 31 .

In the example disclosed herein, each connecting link 31 desirably comprises two laterally spaced parallel rods 32 extending through the respective through holes 30 in the aligned tabs 20 at the one and the another end edges of the one and the another strip sections. Each of the rods 32 has opposite ends extending outwardly beyond respective ends of the through holes 30. Attached to the respective opposite ends of the two rods are a pair of link plates 33 and 34 to maintain a desired lateral spacing between the two rods 32 of each connecting link 31 that is slightly greater than the spacing between the through holes 30 in the respective aligned tabs 20 when the one and the other end edges of the one and the another strip sections are in substantially parallel alignment with one another as shown in Figs. 4 and 5.

One of the link plates 33 may be permanently attached to one of the ends of the two rods 32, whereas the other link plate 34 desirably has a slip fit over the other ends of the two rods, and may be releasably secured to the other ends by a connecting pin 35 that may be transversely slidably received in aligned annular grooves 36 in the other ends of the two rods outwardly of the link plate 34 when the two modular strip sections 1 are placed one on top of another with their top surfaces 2 facing each other as shown in Figs. 7-9 for ease of attachment of the connecting links to the aligned tabs of the two strip sections.

Each of the link plates 33 and 34 of the connecting links 31 used to hingedly connect two or more strip sections 1 together desirably has a width no greater than the thickness of the strip sections, whereby when the joined strip sections are placed on the ground in parallel alignment with one another as schematically shown in Figs. 3-5, the link plates will not interfere with the flat placement of the strip sections against the ground or interfere with automotive vehicle tires passing over the hingedly connected strip sections. Also each of the link plates 33 and 34 has opposite end portions 37 and 38 extending radially outwardly beyond the respective rods 32 when connected thereto a length no greater than one-half the thickness of the strip sections, whereby when the strip sections are folded one on top of another (with their top surfaces 2 facing each other), the ends of the link plates won't extend outwardly beyond the bottom surfaces 3 of the interconnected strip sections as shown in Fig. 8 so as not to interfere with the stacking of multiple folded interconnected strip sections one on top of another. Likewise, the notches 21 , 21 ' and/or 21 " adjacent opposite sides of the tabs 20 have a depth slightly greater than the length of the end portions 37, 38 of the link plates 33, 44 extending radially outwardly beyond the respective rods 32 to allow for the folding of the

interconnected strip sections in overlying relation to one another.

Although the number as well as the length and spacing of the tabs 20 at the end edges 6, 7 of the strip sections 1 that are hingedly connected together may be varied within certain limits depending on the width of the strip sections, the end edges of each of the strip sections preferably have at least two tabs 20, and more preferably three tabs, and still more preferably four tabs at the end edges of each of the strip sections that are hingedly connected together by respective connecting links 31 in order to strengthen the attachment of the interconnected strip sections.

In the example shown herein, wherein four hingedly connected tabs 20 are provided at the end edges of the respective strip sections, the centermost notch 21 between two of the tabs 20 at the end edges of each of the strip sections has a width slightly greater than the length of the two rods 32 of the respective connecting links 31 to facilitate insertion of the free ends of the rods of the respective connecting links through the through holes 30 in the respective aligned tabs 20 of the strip sections as best seen in Figs. 4, 7 and 9. The outermost notches 21 ' desirably extend all the way out to the side edges 4, 5 of the strip sections to facilitate insertion of the free ends of the rods 32 of the connecting links 31 used to hingedly connect the outermost tabs of two strip sections together as also best seen in Figs. 4, 7 and 9. The notches 21 " between the inner and outermost tabs 20 need only have a width sufficient to accommodate the free ends of the rods of the two connecting links connecting the inner and outermost tabs together and the respective link plates 34 that have a slip fit over the free ends of the respective rods and are releasably secured to the free ends by transversely slidably inserting the connecting pins 35 in the aligned grooves 36 in the free ends of the respective rods outwardly of the respective slip-on link plates when the strip sections are folded one on top of another as shown in Fig. 9.

Although the invention has been shown and described with respect to certain embodiments, it is obvious that equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of the specification. In particular, with regard to the various functions performed by the above-described components, the terms (including any reference to a "means") used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component {e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed component which performs the function of the herein illustrated exemplary embodiments of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one embodiment, such feature may be combined with one or more other features as may be desired or advantageous to any given or particular application.