US20080038058A1

US20080038058A1 - Retro-Reflective Pavement Markers

Info

Publication number: US20080038058A1
Application number: US11/835,775
Authority: US
Inventors: Douglas Forrer; Peter Hedgewick
Original assignee: Pac-Tec Inc
Current assignee: Pac-Tec Inc
Priority date: 2006-08-08
Filing date: 2007-08-08
Publication date: 2008-02-14

Abstract

Disclosed is a protector for a retro-reflective road marker mounted in a road that includes a top portion that has a generally flat region where the retro-reflective road marker can be mounted and a bottom portion oppositely disposed from the top portion. The protector is made from a moldable polymer and the top portion is operable to protect the road reflector from motor vehicle tires passing thereover and the bottom portion of the protector has a bottom arcuate surface that defines an arc extending from the top portion.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority of U.S. Provisional Patent Application Ser. No. 60/821,709, filed Aug. 8, 2006, which is incorporated herein by reference.

FIELD OF THE INVENTION

This invention relates generally to a retro-reflective marker for mounting to roads. More specifically, the invention relates to a plastic protector for retro-reflective markers mounted to roads.

BACKGROUND OF THE INVENTION

In many regions, plastic retro-reflective road markers are mounted to the road surface to delineate the lanes. Retro-reflective markers mounted directly onto or into the road surface are damaged by the passing of motor vehicle tires over the markers. In particular, heavy motor vehicles such as trailer-hauling trucks can cause significant damage and shorten the useable lifetime of retro-reflective road markers placed on the highway.
Additionally, it has been difficult to accurately position plastic retro-reflective road markers with respect to the road surface. If the retro-reflective marker is placed too low within the pavement surface, the lens is obscured and there is insufficient light reflected from the lens to delineate the lane. In contrast, if the retro-reflective marker extends too far above the road surface, it can become a hazard for vehicles passing over it and suffers premature damage due to tires passing over it.
Accordingly, it is desirable to have a protector for retro-reflective road markers which properly provides protection for the marker from damage by motor vehicle tires and can be accurately positioned with respect to the road surface.

SUMMARY OF THE INVENTION

Disclosed is a protector for a retro-reflective road marker that includes a top portion with a generally flat region where the retro-reflective road marker can be mounted and a bottom portion oppositely disposed from the top portion. The protector is made from a moldable polymer and the top portion is operable to protect the road reflector from motor vehicle tires passing thereover.
The top portion of the protector has a pair of spaced apart side ramps that are parallel to a longitudinal axis of the protector, the side ramps extending above the bottom portion. The side ramps can each have a flange that extends in a generally outward direction from the longitudinal axis and can support the protector on a top surface of the road when the bottom portion is located within a recess in the pavement. The top portion also has a center portion that extends between the spaced apart side ramps, the center portion having a pair of upper surfaces that extend transversely between the side ramps and are inclined downwardly toward a mounting surface. The retro-reflective road marker can be mounted onto the mounting surface. The upper surfaces can include a center ramp that is aligned on the longitudinal axis of the protector.
The bottom portion of the protector has a bottom arcuate surface that defines an arc when viewed from the side. The bottom arcuate surface extends from the top portion and the arc has a height dimension defined between a bottom surface of the flange and the outermost point of the bottom arcuate surface spaced apart from the bottom surface of the flange. The bottom arcuate surface can include a cavity that extends from the bottom surface towards the top portion. In some instances, the cavity extends generally perpendicular to the longitudinal axis of the protector and has a depth, the depth divided by the height of the arc defining a ratio ranging between 0.2 and 0.8. In other instances, the cavity is generally parallel to the longitudinal axis and extends from the bottom arcuate surface towards the top portion and is directly under one of the center ramps.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of an embodiment of the present invention;
FIG. 2 is a bottom perspective view of an embodiment of the present invention;
FIG. 3 is a bottom view of the embodiment shown in FIG. 2;
FIG. 4 is a side view of the embodiment shown in FIG. 2; and
FIG. 5 is a side cross-sectional view of the section 5-5 shown in FIG. 3.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention includes a plastic protector for a retro-reflective road marker. As such, the present invention has utility as an article that provides protection to road markers placed on the highway to delineate the lanes.
The protector for the retro-reflective road marker is a moldable plastic body of material that includes a top portion and a bottom portion. In some instances, the protector is made from a moldable polymer. The moldable polymer can be a hard, durable material such as polycarbonate. The top portion has a flat surface whereupon the retro-reflective road marker can be mounted and at least two side rails that extend above the retro-reflective road marker mounted onto the flat surface. In some instances, a center ramp can be included between the two side rails, the side rails and/or center ramp affording protection of the retro-reflective road marker from motor vehicle tires passing thereover. The protector can also include a bottom portion that has a bottom arcuate surface in the shape of an arc when viewed from the side. The bottom arcuate surface extends from the top portion. The bottom portion can include at least one cavity that extends from the bottom arcuate surface towards the top portion. The at least one cavity can extend in a direction that is generally perpendicular to a longitudinal axis of the protector or in a direction that is generally parallel with the longitudinal axis. The cavities afford for reduced weight, reduced cross-sectional thickness and increased bottom surface area of the protector.
Referring now to FIGS. 1-5, a low profile protector for a retro-reflective road marker is shown generally at reference numeral 10. The protector 10 includes a top portion 100 and a bottom portion 200. The top portion is operable for a reflector R to be mounted thereto.
The top portion 100 can include a pair of side rails 112 which are spaced apart from each other. Between the side rails 112 is a center portion 150. The center portion 150 includes a pair of upper surfaces 152 that extend transversely between the side rails 112 and are inclined downwardly toward a mounting surface 156. As illustrated in FIG. 1, the retro-reflective road marker R can be mounted to the mounting surface 156. The pair of upper surfaces 152 can also include a slot 154 which affords for the removal of the road reflector R from the protector 10 by use of an instrument that fits at least partially within the slot 154 and applies leverage to the reflector R. For example, a screwdriver can be used to remove the reflector R from the protector 10 by placing the head of the screwdriver (not shown) within the slot 154 and prying up and/or against the reflector R.
Each of the upper surfaces 152 can include a center ramp 162. As illustrated in FIG. 1, the center ramp has a side wall 163 that extends above the upper surface 152. It is appreciated that the pair of side rails 112 and the pair of center ramps 162 extend above the bottom portion 200 to a height such that the reflector R when mounted on the mounting surface 156 is protected by items rolling thereover. In some instances, the height of the center ramps 162 is equal to the height of a plane extending across top surfaces 114 of the pair of side rails 112. In other instances, the height of the center ramps is not equal to the height of the plane extending across top surfaces 114 and is less than or greater than this height.
The pair of side rails 112 include a side wall 113 which extends in a generally upward direction from the bottom portion 200 to the top surface 114. In some instances, the top surface 114 is an arcuate surface that increases in height from an end proximate to an edge 156 of the center portion 150 to the mounting surface 156. In this manner, a pair of low profile protective surfaces is provided for the protection of the reflector R.
The pair of side rails 112 can include a flange 122 that extends in a generally outward direction from a longitudinal axis 110 of the protector 10. Each of the flanges 122 extends beyond the bottom portion 200 and has a bottom surface 123. The bottom surface 123 is a generally flat surface and affords for support of the protector 10 on a pavement surface when the bottom portion 200 of the protector 10 has been placed within a cavity or recess produced within the pavement to accept the protector 10. The use of a recess in the pavement that accepts the bottom portion 200 but is not wide enough for the flanges 122 to fit within affords for accurate and proper placement of the protector 10 with the retro-reflective road marker mounted thereon with respect to lanes of the road.
Referring now to FIG. 2, a bottom perspective view of the bottom portion 200 is shown. The bottom portion 200 can include a side surface 220 extending to a bottom arcuate surface 210, the bottom arcuate surface 210 having the shape of an arc when viewed from the side as shown in FIGS. 4 and 5. In addition, the bottom arcuate surface 210 can have a height dimension h defined by the maximum distance of the bottom surface 210 spaced apart from the bottom surface 123 of the flange 122. In some instances the arc shape has a radius in is between 6½ inches and 8 inches. In other instances, the arc shape has a radius between 7½ inches and 7¾ inches. In still other instances, the arc shape has a radius equal generally to 7 15/32 inches.
The bottom portion 200 can include at least one cavity 222 and/or cavity 242. The cavity 222 extends in a generally perpendicular direction with respect to the longitudinal axis 110 of the protector 10. The cavity 242 extends in a generally parallel direction with the longitudinal axis 110. Both the cavity 222 and the cavity 242 extend from the bottom arcuate surface 210 towards the top portion 100. The cavity 222 and/or cavity 242 afford for an increased surface area of the bottom portion 200. In addition, the cavity 222 and/or cavity 242 afford for a reduction in the average cross-sectional thickness of the protector 10. The increased surface area of the bottom portion 200 that is provided by the cavity 222 and/or cavity 242 affords for increased area that adhesive used to hold the protector 10 within a recess in the pavement surface can adhere to.
In some instances, the cavity 222 and/or cavity 242 are included to afford a relatively consistent thickness of the protector 10 in order to decrease shrinkage and/or warpage during manufacture of the protector 10. As such, the design of a protector for a retro-reflective road marker can use cavities such as those shown in the figures to obtain a generally uniform thickness of the protector in order to reduce shrinkage and/or warpage during the molding process and thereby improve the consistency and/or quality of the product. In addition, a reduction in the average cross-sectional thickness of the protector 10 reduces expansion and contraction of the protector during temperature changes and affords for an increase in the useful lifetime of the retro-reflective road marker R mounted to the mounting surface 156. It is appreciated that the retro-reflective road marker R can be mounted to the protector 10 using any method, device or mechanism known to those skilled on the art, illustratively including adhesives, ultrasonic welding, nuts and bolts, screws and the like.
The cavity 222 has a depth d measured from the arcuate bottom surface 210 to the region of the cavity that is closest to the top portion 100, as illustrated in FIG. 4. In some instances, the depth d of the cavity 222 divided by the height h of the bottom portion 200 defines a ratio that ranges between 0.1 and 0.9. In other instances, the ratio d/h ranges from 0.2 to 0.8. In still other instances, the ratio d/h ranges between 0.25 and 0.5. It is appreciated that if more than one cavity is present, the depth of one cavity can be different than the depth of another cavity. It is also appreciated that the depth within a single cavity can vary.
In an embodiment of the present invention, the protector 10 has a bottom portion 200 with a plurality of cavities 222 and a pair of cavities 242. The cavities 242 extend from the bottom arcuate surface 210 towards the top portion 100 directly under the center ramps 162 on the top portion 100. In this manner, weight reduction and overall thickness of the protector 10 is afforded. Although not required, the protector 10 can include other features such as apertures 212, apertures 261 and slots 262. The apertures 212, 261 and slots 262 afford for increased weight reduction of the protector 10 and for additional surface area and structures for adhesive to bind the protector 10 to the highway. The aperture 212 extends from the bottom arcuate surface 210 towards the top portion 100 and the aperture 261 and slot 262 extend in a generally inward direction from the side surface 220 towards the longitudinal axis 110. In some instances, the aperture 261 has a diameter between ⅛ inch and ½ inch, inclusive, and a depth between 1/16 inch and ½ inch, inclusive. In other instances, the aperture 261 has a diameter of ¼ inch and depth of ⅛ inch.
As is known to those skilled in the art, a recess can be produced in a pavement surface that affords for the bottom portion 200 to fit at least partially within and allows for the flanges 122 to accurately and consistently place the protector 10 relative to the pavement surface. Within such a recess in the pavement, it is common to place an adhesive before positioning the protector therein. Thus the protector 10 is placed on top of and in contact with adhesive that is within the recess in the pavement surface and the adhesive binds to the bottom portion 200. Therefore, an increase in surface area, notches, and slots afford for improved adherence of the protector 10. In particular, structural features such as the aperture 261, when at least partially filled with adhesive, act as anchor or grasping regions for the adhesive and thereby improve the ability of the protector 10 to be held in place on and/or within the road for extended time periods. A stud 260 can also be provided within one of the cavities 222. In some instances, the stud 260 can have a rough or threaded surface in order to increase the surface area and thus increase the adherence of the bottom portion 200 to a highway.
In this manner, a low profile protector for a retro-reflector road marker is provided. The foregoing drawings, discussion and description are illustrative of specific embodiments of the present invention, but they are not meant to be limitations upon the practice thereof. Numerous modifications and variations of the invention will be readily apparent to those of skill in the art in view of the teaching presented herein. It is the following claims, including all equivalents, which define the scope of the invention.

Claims

1. A protector for a road reflector mounted in a road, said protector comprising:

a body having a top portion and a bottom portion, said top portion having a generally flat region; and

a road reflector mounted on said generally flat region of said top portion;

said top portion also having a structure extending above said generally flat region where said road marker is mounted, said structure operable to protect said road reflector from motor vehicle tires passing over said road reflector;

said bottom portion oppositely disposed from said top portion and mounted in a road;

said top portion and said bottom portion made from moldable polymer.

2. The protector as claimed in claim 1, wherein said structure is a pair of spaced apart side rails parallel to a longitudinal axis of said protector, said side rails extending above said bottom portion.

3. The protector as claimed in claim 2, wherein each of said pair of spaced apart side rails has a flange extending in a generally outward direction from said longitudinal axis, said flanges operable to support said protector on a top surface of the road.

4. The protector as claimed in claim 2, wherein said top portion has a center portion extending between said rails, said center portion having a pair of upper surfaces extending transversely between said rails and inclined downwardly toward a mounting surface.

5. The protector as claimed in claim 4, wherein said road reflector is mounted onto said mounting surface.

6. The protector as claimed in claim 4, wherein each of said pair of upper surfaces has a center ramp aligned on said longitudinal axis.

7. The protector as claimed in claim 2, wherein said bottom portion has a bottom arcuate surface, said bottom arcuate surface defining an arc extending from said top portion, said arc having a height between a bottom surface of said flange and said arc surface.

8. The protector as claimed in claim 7, wherein said bottom arcuate surface has a cavity extending from said bottom surface towards said top portion.

9. The protector as claimed in claim 8, wherein said cavity extends generally perpendicular to said longitudinal axis.

10. The protector as claimed in claim 9, wherein said cavity extending generally perpendicular to said longitudinal axis has a depth, said depth divided by said height of said arc defining a ratio ranging between 0.2 and 0.8.

11. The protector as claimed in claim 8, wherein said cavity is generally parallel to said longitudinal axis.

12. The protector as claimed in claim 11, wherein said cavity extends from said bottom surface towards said top portion directly under said center ramp.

13. The protector as claimed in claim 7, wherein said bottom portion has an aperture extending from a sidewall of said bottom portion in a generally inward direction towards said longitudinal axis.

14. A protector for a road reflector mounted in a road, said protector comprising:

a road reflector mounted on said generally flat region of said top portion;

said top portion also having a pair of flanges extending in a generally outward direction from said protector and a structure extending above said generally flat region where said road marker is mounted, said flanges operable to support said protector on a top surface of the road and said structure operable to protect said road reflector from motor vehicle tires passing over said road reflector and;

said bottom portion oppositely disposed from said top portion and mounted in a road, said bottom portion having a bottom arcuate surface;

said bottom arcuate surface defining an arc extending from said top portion, said arc having a height between a bottom surface of said flange and said arc surface;

said top portion and said bottom portion made from moldable polymer.

15. The protector as claimed in claim 14, wherein said structure has a pair of spaced apart side rails parallel to a longitudinal axis of said protector and extending above said bottom portion, said pair of flanges extending from said pair of side rails.

16. The protector as claimed in claim 14, wherein each of said pair of spaced apart side rails has one of said pair of flanges extending in a generally outward direction from said longitudinal axis.

17. The protector as claimed in claim 16, wherein each of said pair of upper surfaces has a center ramp aligned on said longitudinal axis.

18. The protector as claimed in claim 14, wherein said bottom arcuate surface has a cavity extending from said bottom surface towards said top portion.

19. The protector as claimed in claim 18, wherein said cavity extends generally perpendicular to said longitudinal axis.

20. A protector for a road reflector mounted in a road, said protector comprising:

a body having a top portion and a bottom portion oppositely disposed from said top portion;

said top portion having a pair of spaced apart side rails parallel to a longitudinal axis of said protector and extending above said bottom portion, said pair of side rails each having a flange extending in a generally outward direction from said protector and operable to support said protector on a top surface of the road;

said top portion also having a center portion extending between said side rails, said center portion having a pair of upper surfaces extending transversely between said side rails and inclined downwardly toward a mounting surface; and

a reflector mounted on said mounting surface;

said pair of upper surfaces each having a center ramp aligned on said longitudinal axis and extending in a generally upward direction from said upper surface;

said bottom portion having a bottom arcuate surface defining an arc extending from said top portion, said arc having a height between a bottom surface of said flange and said arc surface, said bottom arcuate surface having a cavity extending from said bottom surface towards said top portion;

said top portion and said bottom portion made from moldable polymer.