US20140270940A1

US20140270940A1 - Channelizer post

Info

Publication number: US20140270940A1
Application number: US13/830,128
Authority: US
Inventors: Dennis A. Butler; Craig Michael Schulz
Original assignee: Pexco LLC
Current assignee: Pexco LLC
Priority date: 2013-03-14
Filing date: 2013-03-14
Publication date: 2014-09-18

Abstract

A channelizer post suitable for delineating traffic lanes, identifying road gore zones, road verges, and pedestrian areas, and the like, is disclosed. While replaceable, the post is normally permanently installed. The post has spring-back capabilities, such that after the post is hit by an object such as a vehicle, the post springs back to a normal vertical position. The post includes a capped tube, preferably formed of an engineered plastic, such as UV stabilized thermoplastic polyurethane (TPU) and a base also preferably formed of an engineered plastic, such as a UV-stable high-impact thermoplastic alloy. The plastics are such that they are weldable together when the post is formed. The cap includes a plurality of holes that allow air to escape from the capped tube when the post is hit by an object and air to reenter the capped tube when the post springs back to its normal vertical position. Molded into the base is a threaded bolt designed to thread into a threaded cup permanently installed in a roadway or other location. Finally, located inside of the vertical component is a kicker tube, preferably formed of the same material as the tube and the cap. All of the plastic components are welded to one another.

Description

BACKGROUND

Products for delineating areas, such as traffic lanes, road gore zones, road verges, and pedestrian areas, are well known and widely available. Many delineator products are surface items, such as painted stripes and plastic strips attached to an underlying surface, e.g., a roadway, by an adhesive. Some delineator products have vertical components formed of plastic materials that are mounted on bases that are placed at temporary locations during construction in order to delineate temporary traffic lanes, for example. Some delineator products with vertical components are more permanently attached to support elements, such as caps affixed to or embedded in an underlying surface. Some such delineator products are sometimes referred to as delineator or channelizer posts.
One of the problems with prior delineator or channelizer posts that are intended to be permanently installed at particular locations is their ease of destruction when impacted by an object, such as a vehicle, i.e., an automobile, truck, bus, etc. In the past, the components that have been used to create such posts have been mechanically or adhesively attached to one another. Also, such posts often have had a hole or several holes punched into them. Holes create notches or failure points that elongate or tear under stress. Adhesive attachment and other manufactured failure points created by holes result in premature post failure, both where post components are adhesively attached and where the holes are located when a post is impacted by an object such as a vehicle. When failure occurs, rather than springing back to a normal upright position, the posts must be removed and replaced with new posts, which is both time consuming and expensive and subjects roadworkers to potential risk of injury or death.

SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.
A channelizer post for use in delineating traffic lanes, identifying road gore zones and verges, identifying pedestrian areas, etc., is disclosed. The channelizer post is designed to spring back to a normal upright or vertical position after being impacted by an object, such as an automobile. The channelizer post includes a base formed of a suitable plastic that includes a threaded bolt designed to be screwed into a threaded cup permanently installed in an underlying surface. Preferably, the threaded bolt is molded into the plastic base. The channelizer post also includes a hollow vertical tube and may also include an optional cap, also formed of a suitable plastic. While not necessary to perform the function of the channelizer post, ideally a top cap serves to keep out water and prevents rubbish from being thrown into the hollow tube. The plastics used to form the base, hollow tube, and the cap are sufficiently compatible such that the hollow tube is weldable to the base, and the cap is weldable to the top of the hollow tube. The cap includes holes that allow air to leave and enter the hollow tube when, after installation, the channelizer post is hit by an object, such as the nose of an automobile, and thereafter the hollow tube springs back to its normal vertical position. Preferably, these are the only holes in the channelizer post.
The cap and the hollow tube are preferably formed of an engineered plastic, such as UV stabilized thermoplastic polyurethane (TPU). Also, preferably, the base is formed of a UV-stable high-impact thermoplastic alloy. As noted above, the chosen plastics are designed to be weldable to one another. Preferably, the base, the hollow tube, and the cap are cylindrical and spin welded together.
Also disclosed is a plastic kicker tube located inside of the outer tube. The kicker tube is welded to the base.
As will be readily appreciated by those skilled in the art and others, welding the various components of the channelizer post to one another and limiting the inclusion of holes to the cap creates a channelizer post that is less susceptible to failure than prior posts.

DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 illustrates an exemplary embodiment of a channelizer post formed in accordance with the disclosure just prior to impact by the nose of an automobile;

FIG. 2 illustrates how the channelizer post illustrated in FIG. 1 might deform in response to being impacted by the nose of the automobile;

FIG. 3 illustrates how the channelizer post illustrated in FIG. 1 might deform when the tire of an automobile runs over the channelizer post;

FIG. 4 illustrates an exemplary embodiment of a channelizer post formed in accordance with the disclosure and a cup suitable for receiving the post after being embedded in an underlying surface, e.g., a roadway;

FIG. 5 is an exploded view of the channelizer post illustrated in FIG. 4; and

FIG. 6 is a series of views illustrating the manufacturing steps used to construct the channelizer post illustrated in FIGS. 4 and 5.

DETAILED DESCRIPTION

As will be better understood from the following description, a channelizer post that is ideally suited for delineating traffic lanes, identifying road gore zones and verges, identifying pedestrian areas, and the like is disclosed. For example, channelizer posts of the type disclosed are ideally suited for use in delineating where bike lanes adjoin automobile traffic lanes in urban thoroughfares and for assisting in identifying raised traffic medians in urban thoroughfares. Channelizer posts of the type disclosed are also ideally suited for use in delineating various types of roadway areas, such as road gores, and in separating verges located along roads from an adjacent road. Channelizer posts of the type disclosed can also be used to help define the edge of pedestrian plazas. As will be readily appreciated, the foregoing should be taken as examples of potential uses of channelizer posts of the type disclosed and not as limiting.
As will also be better understood from the following descriptions, channelizer posts of the type disclosed are designed to spring back to a normal upright or vertical position after being impacted by an object, such as the nose of an automobile, for example. In this regard, attention is directed to FIGS. 1, 2, and 3.
FIG. 1 illustrates the front end or nose 12 of an automobile 11 just prior to the nose impacting a channelizer post 13 of the type disclosed herein. As shown, just prior to impact, the channelizer post 13 is vertical. FIG. 2 shows, just after impact, the channelizer post 13 being “wrapped” around the nose 12 of the automobile 11. This depiction should be taken as exemplary and not as limiting. More specifically, FIG. 2 illustrates the base 21 of the channelizer post 13, which is attached to an underlying surface 14, such as a roadway, as located beneath the nose 12 of the automobile 11. The vertical component of the channelizer post 13 is shown as partially wrapped around the nose 12 of the automobile 11. After impact, the automobile can entirely roll over the channelizer post 13 or the automobile can be reversed and backed off the channelizer post. Regardless of how the automobile “clears” the channelizer post, after the channelizer post is cleared, the vertical component of the post returns to its normal vertical position, which is shown in FIG. 1.
Even if the channelizer post is rolled over by the tire 15 of the automobile 11, as shown in FIG. 3, after the automobile “clears” the area of the post, the vertical component returns to its normal upright, i.e., vertical position. Thus, even such an impact does not cause the channelizer post to fail under normal circumstances. Obviously, multiple impacts of this type over time could result in failure.
FIG. 4 illustrates an exemplary embodiment of a channelizer post is formed in accordance with this disclosure. FIG. 5 is an exploded view of the exemplary embodiment illustrated in FIG. 4. FIG. 6 is a sequence of views illustrating the manufacturing steps employed in creating the exemplary embodiment.
The channelizer post 13 illustrated in FIGS. 4, 5, and 6 includes the base 21, a hollow outer tube 23, a cap 25, and a kicker tube 27, all formed of plastic materials that are weldable to one another. The base 21 is generally cylindrical in shape and includes a serrated outer periphery that allows it to be gripped by a suitable gripping tool, such as channel lock pliers, for example, during installation. More specifically, extending downwardly from the main (plastic) part of the base 21 is a threaded metal bolt 29 designed to be inserted into a threaded hole in a cup 31 during installation of the channelizer post. As shown in FIGS. 1 and 2, the cup 31 is designed to be permanently installed in an underlying surface 14, such as a roadway. For example, the cup 31 could be cemented into a concrete roadway or installed in an asphalt roadway when the asphalt roadway is laid down, or later by heating and softening the asphalt roadway after drilling a hole. Preferably, the threaded bolt 29 is molded into the plastic base.
The upper surface of the base 21 includes a center circular aperture 33, which receives the lower end of the kicker tube 27. The kicker tube 27 is welded to the base 21. As shown, both the base and the kicker tube are cylindrical in shape. The currently preferred way of welding these components together is spin welding.
Surrounding the center circular aperture 33 is an outer ring-shaped circular aperture 35, which receives the lower end of the outer tube 23. As with the kicker tube, preferably, the lower end of the outer tube is spin welded to the base 21. The cap 25 is installed in the upper end of the outer tube 23. As with the other components, preferably, the cap 25 is spin welded to the upper end of the outer tube 23. The cap 25 includes a plurality of holes 37, which allow air to leave the tube 23 if the outer tube 23 partially collapses when the channelizer post is hit by an object, such as the nose of an automobile as shown in FIG. 2, or run over by a tire, as shown in FIG. 3, and allow air to reenter the tube when the outer tube 23 returns to its normal cylindrical shape and normal vertical position shown in FIG. 1.
FIG. 6 illustrates in more detail the process for making the delineator post illustrated in FIGS. 4 and 5. Initially, in step A, the bolt 29 is molded into the generally cylindrical base 21. In one actual embodiment, the base was constructed of a UV-stable high-impact thermoplastic alloy having the following properties:


Property	ASTM Test	Results

Specific Gravity (min.)	D 792	1.21
Gardner impact (min.)	N/A	160
Flexural Strength (min.)	D 790	20,000
Shore Hardness	D 2240	55 D

As shown in step B of FIG. 6, next, one end of the kicker tube 27 is spin welded to the center circular aperture 33 in the base 21. Then, as shown in step C, the lower end of the outer tube 23 is spin welded to the base 21. Finally, the cap 25 is spin welded to the top of the outer tube 23.
In one actual embodiment referenced, the outer tube had a diameter of 3.15 inches and a wall thickness of 0.125 inch. The material used in this embodiment to form the kicker tube (which had a smaller diameter), the outer tube, and the cap was a UV-stabilized thermoplastic polyurethane (TPU) having the following properties:


Property	ASTM Test	Results

Specific Gravity (min.	D 792	1.10
Hardness (min.)	D 2240	90 A
Tear Strength (min. lb/in.)	D 624, Die C	800
Tensile Strength @ yield (min PSI)	D 412	4,000
Tensile Elongation @ break (min %)	D 412	450
Cold Temp. Impact Test (−7° F.)	FL/DOT	Pass
Gloss (min. units)	N/A	12.1

In the manufacture of the actual embodiment referenced above, the kicker and outer tube were held stationary during spin welding. The base or cup was spun in the 800-1300 rpm range and pressure in the 50-150 psi range was applied, depending on the parts being welded. As a specific example, the outer tube was spun at 1300 rpm and 150 psi applied for 5.6 seconds. Spinning of the base stopped immediately after complete insertion and the components held for 7 seconds to allow sufficient cooling time to set up. The melt window of the resins was 15 degrees. The end result is molecular adhesion between the parts that occurs when plastic parts are spin welded together.
While the illustrated embodiment is cylindrical and the parts are welded together using spin welding, other types of plastic welding techniques, such as ultrasonic and high frequency vibration can be used. Further, while the illustrated embodiment is cylindrical in shape, if desired, other cross-sectional configurations can be used, such as oval, triangular, square, rectangular, etc. Obviously, the parts of non-cylindrical embodiments cannot be spin welded together. Rather, other types of plastic welding techniques, such as those noted above, i.e., ultrasonic and high frequency vibration welding techniques, must be used. Finally, if desired, depending on use, one or more rings of reflective tape 41 can be wrapped around the upper end of the outer tube as shown in FIGS. 1 and 2.
While a preferred embodiment has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the claimed subject matter.

Claims

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A channelizer post suitable for use in delineating regions such as traffic lanes, pedestrian areas, road gore zones, road verges, and the like, comprising:

a plastic base including a post suitable for attachment to an embedded retaining device; and

a hollow plastic tube suitable for attachment at one end to the plastic base;

wherein: (i) the plastics used to form the plastic base and the hollow plastic tube are weldable to one another; and (ii) the plastic base and the hollow plastic tube are welded to one another.

2. The channelizer post claimed in claim 1, including a plastic cap suitable for attachment to the other end of the hollow plastic tube, wherein: (i) the plastic used to form the plastic cap is weldable to the hollow plastic tube; and (ii) the plastic cap is weldable to the hollow plastic tube.

3. The channelizer post claimed in claim 2, wherein the cap includes holes.

4. The channelizer post claimed in claim 2, wherein the plastic base, the hollow plastic tube, and the plastic cap are generally cylindrical in shape.

5. The channelizer post claimed in claim 4, wherein the cap includes holes.

6. The channelizer post claimed in claim 4, wherein the plastic base, the hollow plastic tube, and the plastic cap are spin welded to one another.

7. The channelizer post claimed in claim 5, wherein the cap includes holes.

8. The channelizer post claimed in claim 2, also including a kicker tube formed of plastic that is weldable to the plastic used to form the base and wherein the plastic kicker tube is welded to the plastic base.

9. The channelizer post claimed in claim 8, wherein the cap includes holes.

10. The channelizer post claimed in claim 8, wherein the plastic kicker tube, the plastic base, the hollow plastic tube, and the plastic cap are generally cylindrical in shape.

11. The channelizer post claimed in claim 10, wherein the kicker tube, the plastic base, the hollow plastic tube, and the plastic cap are spin welded together.

12. The channelizer post claimed in claim 10, wherein the cap includes holes.

13. The channelizer post claimed in claim 8, wherein the plastic kicker tube is located inside of the hollow plastic tube.

14. The channelizer post claimed in claim 13, wherein the cap includes holes.

15. The channelizer post claimed in claim 2, wherein the plastic base, the hollow plastic tube, and the plastic cap are generally cylindrical in shape.

16. The channelizer post claimed in claim 15, wherein the plastic kicker tube, the plastic base, the hollow plastic tube, and the plastic cap are spin welded to one another.

17. The channelizer post claimed in claim 16, wherein the cap includes holes.

18. The channelizer post claimed in claim 16, wherein the plastic kicker tube is substantially shorter than the hollow plastic tube.

19. The channelizer post claimed in claim 1, wherein the hollow plastic tube and the plastic base are generally cylindrical in shape.

20. The channelizer post claimed in claim 19, wherein the hollow plastic tube and the plastic base are spin welded to one another.