US3626638A - Wrong-way traffic safety barrier - Google Patents

Abstract

A SAFETY BARRIER IS PROVIDED TO PREVENT WRONG-WAY TRAFFIC FROM ENTERING A ONE-WAY STREET. THE BARRIER IS FORMED BY ONE OR MORE METAL PANS WHICH EXTEND TRANSVERSELY ACROSS THE ROADWAY. EACH PAN IS HINGED TO THE ROADWAY ON ITS LONGITUDINAL SIDE WHICH IS FIRST ENCOUNTERED BY VEHICLES MOVING IN THE NORMAL DIRECTION OF TRAFFIC FLOW. SPRING MEANS ARE PROVIDED UNDERNEATH THE PAN FOR NORMALLY HOLDING THE PAN IN AN ANGLED, ELEVATED POSITION. THE OTHER, NORMALLY ELEVATED LONGITUDINAL EDGE OF THE PAN IS PROVIDED WITH A DOWNWARDLY TURNED FLANGE WHICH IS CLEARLY VISIBLE TO TRAFFIC APPROACHING FROM THE WRONG DIRECTION, AND GIVES THE APPARATUS OF A CURB.

Description

14, 1971 E. J. WQLA FFERTY 3,625,638

WRONG-WAY TRAFFIC SAFETY BARRIER 2 Sheets-Sheet 1 Filed Aug. 5, 1970 IIIIIIIIIIII III IIIIIII II a: In. I:

(MM/L /wm United States Patent 3,626,638 WRONG-WAY TRAFFIC SAFETY BARRIER Edward J. W. Laiferty, 1749 /2 Westmoreland Ave., Los Angeles, Calif. 90006 Filed Aug. 5, 1970, Ser. No. 61,057 Int. Cl. E01f 13/00 US. Cl. 49-49 Claims ABSTRACT OF THE DISCLOSURE A safety barrier is provided to prevent wrong-way traffic from entering a one-way street. The barrier is formed by one or more metal pans which extend transversely across the roadway. Each pan is hinged to the roadway on its longitudinal side which is first encountered by vehicles moving in the normal direction of traflic flow. Spring means are provided underneath the pan for normally holding the pan in an angled, elevated position. The other; normally elevated longitudinal edge of the pan is provided with a downwardly turned flange which is clearly visible to traffic approaching from the wrong direction, and gives the appearance of a curb.

In the operation of the device the wheel of a vehicle traveling in the normal trafiic direction first depresses the pan, and then holds it flat until the Wheel has passed over it, when the spring means returns the pan to its normally elevated position. A vehicle approaching in the wrong direction, however, strikes the raised edge of the pan, producing an impact similar to that experienced in driving over a curb, and thus providing an extremely clear warning to the driver of the vehicle that something it wrong.

The purpose of the above abstract is to provide a nonlegal technical statement of the disclosure of the contents of the instant patent application and thus serve as a searching-scanning tool for scientists, engineers and researchers. Accordingly, this abstract is not intended to be used in understanding or otherwise comprehending the principles of the present invention hereinafter described in detail, nor is it intended to be used in interpreting or in any way limiting the scope or fair meaning of the claims appended hereto.

BACKGROUND OF THE INVENTION Increasing congestion of cities has provided a rapid increase in the number of streets that are routed for traffic in one direction only. A continuing problem with such one-way traffic patterns, unfortunately, is that drivers frequently fail to see the signs indicating that a particular street is limited to trafiic flow in one particular direction. Many trafiic accidents are caused as a result.

A problem which appears even more acute exists at the olf-ramps of freeways. Here the vehicles leaving a freeway frequently travel at very high speeds, much higher than normally encountered in trafiic on city streets. The problem is made even worse by the fact that the trafirc which exits on any one particular off-ramp may be quite irregular or spasmodic, with the result that a driver approaching from the wrong direction may find the off-ramp entirely empty and hence an inviting place on which to drive. In recent times many head-on collisions have occurred on freeway off-ramps and many persons have died as a result.

SUMMARY OF THE INVENTION The basic concept of the present invention is to present to the wrong-way driver the appearance of a curb extending across and hence blocking the roadway which he proposes to enter. The rationale behind this concept is believed quite significant. First, an automobile driver, or

3,626,638 Patented Dec. 14, 1971 any human being for that matter, has a practical understanding of things which he can see and feel, which often cannot be achieved on a conceptual basis alone. Every driver has seen a curb, almost every driver at some time or other has run over a curb in the wrong (upward) direction and hence has learned that he should try to avoid that experience. So the visibility of the simulated curb, as an apparent physical barrier, is extremely important. Even if it is assumed, theoretically, that the curb is no better a warning sign than the normal roadway sign placed in an elevated position above the street surface, the fact remains that when the driver is looking in one particular direction he only sees whatever thing is in his line of sight, hence if he is looking down at the roadway surface he would see the simulated curb but would not see the elevated sign.

A second basis for the rationale of the present invention is the physical impact which results if the wrong-way driver does attempt to enter the roadway. His vehicle strikes something which, initially, provides an impact like striking a curb, however, the simulated curb of the present invention has a fairly limited mass, and when struck by a wrong-way vehicle it will depress with sufficient rapidity so that the total shock to the vehicle is much less than that resulting from driving upward over a conventional curb structure. However, initially, for the first small fraction of a second the reaction is the same. This initial, split-second reaction is very important, because the entire object and purpose of the present invention is to convey a necessary warning message to the driver in order to save his life and the lift of other drivers.

Thus, the primary object and purpose of the present invention is to provide a simple but eifective safety device which will prevent drivers from entering a one-way roadway from the wrong direction. More specifically, the object of the invention is to provide such a device which is economical to make and install, reliable in operation, and has a long useful life.

According to the preferred form of the invention the exposed vertical wall portion "of the simulated curb is provided either with individual reflectors or with light reflecting material, so that when approached at night it will provide a clearly visible warning to the wrong-way driver.

DRAWING SUMMARY FIG. 1 is a perspective view of a freeway exit ramp across which a simulated curb has been installed in accordance with the present invention.

FIG. 2 is a top plan view of two of the curb sections of FIG. 1.

FIG. 3 is a vertical cross-sectional view taken on the line 3-3 of FIG. 2.

FIG. 4 is a vertical cross-sectional view taken on the line 44 of FIG. 2.

FIG. 5 is a vertical cross-sectional view taken on the line 5-5 of FIG. 4.

FIG. 6 is a vertical cross-sectional view like FIG. 4, but shows the simulated curb section in its depressed position.

PREFERRED EMBODIMENT 1 Reference is now made to the drawing, FIGS. 1 to 6 inclusive, illustrating the presently preferred embodiment of the invention.

As shown in FIG. 1 a freeway exit ramp 10 is bounded by curbs 11, 12 on respective sides thereof, and the forward end of the exit ramp 10 discharges into a cross street 13. A row of simulated curb members 20, 40 extend across the end of the exit ramp 10, so that any motorist attempting to enter the exit ramp 10 from the cross street 13 would be confronted by the row of simulated curb devices.

Referring now to the other dramings, each curb device 20 has an elongated rectangular configuration, being for example about two feet wide and about three feet long. Any required number of the simulated curb devices 20 are placed in end-to-end relationship in order to extend across the main portion of the exit ramp The curb devices 40 are used at the ends and each of the devices 40 has one end which is square, for fitting with the adjoining square end of a curb device 20, and the other end of the curb device 40 is curved in such manner as to fit closely beside a curved portion of the permanent street curb 11 or 12. Thus, the curb devices 40 are generally the same in their structure and operation as the curb devices 20 but are simply made of a different shape in order to more conveniently fill the space between the permanent standard curbs of the freeway exit ramp 10.

Each simulated curb member 20 includes, as its principal element, a metal pan having a flat generally rectangular top portion 21 with a longitudinal edge 22 which is herein, rather arbitrarily, referred to as the rear edge of the pan. The rear edge 22 of the pan is hingedly supported at the roadway surface, as best seen in FIGS. 3, 4 and 6. The other longitudinal edge 23 of the pan is normally elevated, and has a downwardly turned front flange 24 which prtr vides the vertical wall surface of the simulated curb. The angle between the front flange 24 and the fiat portion 21 of the pan is made somewhat less than 90, so that in the normally elevated position of the pan as shown in FIG. 4 the front wall 24 is aligned in a precisely vertical position, or nearly so. For example, where the width of the pan between rear edge 22 and front edge 23 is about two feet the exposed portion of the front vertical wall 24 may be about eight inches. The flat portion 21 of the pan, in its raised position, then forms an angle with the roadway surface of about 20, and the angle between the flat pan portion 21 and the front flange 24 is about 70.

In order to install the wrong-way traflic safety barrier of the present invention in an existing street, a hinge recess 14 is cut in the roadway surface across the entire width of the roadway at the location that is desired for the hinged rear edges 22 of the simulated curb devices. FIG. 3 illustrates the hinge recess 14, which may typically be about four inches wide and about eight inches deep. A hinge bar 30, preferably of cylindrical configuration, is installed in the upper portion of the hinge recess 14, so that it extends across the entire width of the roadway and lies only slightly below the roadway surface. A number of anchor bolts 50 have previously been placed in vertical alignment under the hinge bar 30, with the upper end of each anchor bolt 50 being welded to the hinged bar as shown in FIG. 3. A large washer 51 is secured to the lower end of each anchor bolt 50. The depth of cut that is made for the hinge recess 14 may be so adjusted that the hinge bar assembly, including hinge bar 30, anchor bolts 50, and washers 51, may be lowered down into the recess and thereby establish the proper elevation of the hinge bar 30. After positioning of the hinge bar assembly the recess 14 is substantially filled with concrete which then forms an anchor for the hinge bar assembly. It will be noted from FIG. 3 that a pocket 16 is maintained in the upper surface of the concrete anchor 15, so that the hinge bar 30 is exposed and adequate working space is available around it. The hinge bar 30 throughout its full length is supported by at least two, and preferably several of the anchor bolts 50.

A number of hinge straps 3-5 are placed on the hinge bar 30 at positions intermediate to the anchor bolt 50. In general, the requirement is that there be at least two of the hinge straps 35 for each metal pan 20. Each hinge strap 35 has a curved end which encircles the hinge bar 30, and also has a flat end which is attached underneath the pan and Welded thereto, as best seen in FIGS. 3 and 5. One assembly procedure involves attaching the hinge straps 35 to the hinge bar 30 as part of the hinge bar assembly, and then welding the straps 35 to the metal pan only after the hinge bar assembly has been installed in the roadway. Another procedure which may be used is to manufacture the pan, its attached parts, and the hinge bar assembly, and fabricate the entire structure as one integrated assembly before delivering it to the field for installation. It will be seen that the hinge pocket 16 provides adequate working space for the hinge strap 35 so that they may freely rotate about the hinge bar 30.

The front flange 24 is preferably reinforced by means of an L-shaped reinforcing bar 25, welded to the upper portion of the wall 24 on its interior surface. A plurality of reflector devices 28 may be attached to the outer, normally exposed surface of the wall 24. A smaller L- shaped metal bar 26 is attached to the outer-wall surface of the wall 24 at its lower edge and a flat strip 27 of fiber belting material or the like is attached beneath the horizontal portion of the member 26.

A front flange recess 19 is cut into the roadway surface, across the entire width of the roadway, where the simulated curb walls 24 are to be positioned. The front flange recess 19 is therefore parallel to the hinge recess 14, and may have about the same dimensions, such as approximately four inches by eight inches. In the elevated position of the pan 20 as shown in FIG. 4, the front flange 24 is raised above the front flange recess 19, but the web strip 27 does occupy the upper portion of the recess 19 and maintain closure of the recess so that no excessive amount of dirt and trash can be spilled down into recess 19. In the depressed condition of the pan, as shown in FIG. 6, the web strip 27 is positioned at the very bottom center of the recess 19, and the rounded front edge 23 of the pan member comes sufficiently close to the flat forward wall of the recess 19 so that it is effective in keeping out dirt and the like.

Each pan member 20 is normally held in its angled, ele vated position by means of springs 36. At least two of the springs 36 are required for each pan member 20. A number of spring recesses 18 are formed in the roadway surface in front of the hinge recess 14. As best seen in FIG. 2 all of the anchor bolts 50, hinge straps 35, and spring 36 (with associated spring recess 18) are spaced longitudinally of the hinge bar 30, so that no two of these devices occupy the same longitudinal position relative to the hinge bar.

FIGS. 4 and 6 illustrate the spring action. A fiat spring plate 37 is placed in each spring recess 18. An anchor bolt 38 has its upper end welded to the under surface of spring plate 37, and a vertical hole is formed so that the anchor bolt 38 may be driven downward into the roadway material and thereby firmly retain the spring plate 37 in place. Each spring 36 is an elongated fiat strap of spring steel, the forward end portion 41 being of a normally flat configuration and being welded to the under surface of the rectangular pan 20 in its front portion near the wall 24. The central portion of the spring 36 is bent somewhat away from the pan 21 and its rearward end portion 42 is curved back in the direction toward the pan. The rearward end portion 42 of the spring 36 engages the spring plate 37 with a sliding contact. When the pan 20 is depressed, the central and rearward end portions of spring 36 are bent toward the pan, and the curved rearward end 42 of the spring slides rearwardly on the spring plate 37 until the depressed position shown in FIG. 6 is reached.

The operation of the device is as follows. When a vehicle is traveling on the exit ramp 10 in the normal direction of traffic flow, the vehicle wheel 60 first strikes the rear edge 22 of the pan 20, and very soon causes the pan to depress downwardly to the position shown in FIG. 6. Then when the particular wheel has traversed the full width of the pan, the resilient action of spring 36 raises the pan back to its normal elevated position as shown in FIG. 4. The driver of the vehicle experiences some sensation of having struck an obstacle, but the impact is a mild one and entirely consistent with the speed which the vehicle should be traveling upon exiting from the freeway exit ramp. For normal traflic, flowing in the proper direction, the device has the effect of reducing the traffic speed somewhat but presents no difliculties.

When a wrong-way driver confronts the simulated curb of the present invention, the chances are very good that he will see the curb and will not enter the freeway exit ramp. If he does enter, however, his entering speed would normally be rather slow because of the fact that the exit ramp empties into a cross street. In making the corner from the cross street into the exit ramp the driving speed would normally be 25 m.p.h. or less. At this kind of a driving speed the wrong-way driver receives a very noticeable jolt upon striking the simulated curb, but the probability of any damage being caused to the vehicle or injury to the driver is very small, if it exists at all. In this connection it may be noted that the forward edge 23 of the pan is somewhat rounded, where the depending flange 24 is attached, and while the present drawings illustrate a rather small radius of curvature for the curved edge 23 it may be desired to use a larger radius of curvature, and thereby diminish somewhat the impact presented to the wheel of an approaching vehicle. FIG. 4 shows, in dotted lines, the wheel 61 of a vehicle which is approaching the barrier from the wrong direction.

The invention has been described in considerable detail in order to comply with the patent laws by providing a full public disclosure of at least one of its forms. However, such detailed description is not intended in any way to limit the broad features or principles of the invention, or the scope of patent monopoly to be granted.

What is claimed is:

1. A wrong-way traffic safety barrier comprising:

a flat generally rectangular metal pan disposed over a roadway and extending transversely to the direction of trafiic flow;

means hingedly supporting the rear longitudinal edge of said pan at the roadway surface, the front longitudinal edge of said pan having a downwardly turned front flange;

spring means supported from the roadway underneath said pan and normally holding said pan in an angled elevated position above the roadway surface such that the exposed portion of said front flange provides a clearly visible simulated curb constituting a physical barrier to wrong-way traflic; front flange recess formed within the roadway and within which said front flange may be received when the front longitudinal edge of said pan is depressed; whereby the wheel of a vehicle traveling in the normal direction first encounters the rear edge of said pan,

and then depresses said pan and holds it in a depressed position until passing over the front edge of said pan; and

the weight of said pan and the strength of said spring means being such that when a wrong-way vehicle strikes said front edge of said pan, a shock wave is effectively transmitted to the vehicle driver as a warning signal, but said pan nonetheless depresses with suflicient rapidity to avoid damage to the (vehicle.

2. A safety barrier as claimed in claim 1 having light reflecting material on the normally exposed portion of said front flange.

3. A safety barrier as claimed in claim 1 wherein said front flange is disposed at an angle somewhat less than to the undersurface of said metal pan.

4. A safety barrier as claimed in claim 1 wherein said front longitudinal edge of said metal pan is smoothly curved at the juncture between the flat generally rectangular portion thereof and said downwardly turned front flange thereof.

5. A safety barrier as claimed in claim 3 which further includes a horizontal flange attached to the lowermost extremity of said front flange and extending forwardly therefrom.

6. A safety barrier as claimed in claim 1 wherein said pan, in its depressed position, rests directly upon the road way surface intermediate the front and rear longitudinal edges of said pan.

7. A safety device as claimed in claim 1 wherein the width of said pan is approximately two feet and the front longitudinal edge thereof, in its raised position, is approximately eight inches above the roadway surface.

8. A safety barrier as claimed in claim 1 which further includes a hinge recess formed in the roadway beneath said rear longitudinal edge of said pan, and a hinge bar supported within said hinge recess slightly below the roadway surface.

9. A safety barrier as claimed in claim 1 which further includes a cylindrically shaped hinge bar, a plurality of hinge straps each having one end rotatably supported on said hinge 'bar and its other end secured to the under surface of said rear longitudinal edge of said pan, and a plurality of anchor bolts having their upper ends bolted to the under surface of the said hinge bar and extending downwardly therefrom;

a hinge recess being formed within the roadway surface, and said hinge bar assembly being disposed within said hinge recess with said anchor bolts thereof being covered by concrete forming a hinge anchor.

10. A safety barrier as claimed in claim 1 wherein said spring means includes a pair of flat springs having a fixed support at one end and a sliding support at the other end.

References Cited UNITED STATES PATENTS Re. 20,157 11/ 1936 Goodman 4949 3,134,184 5/1964 Neblett 4949 X 2,762,145 9/1956 Rupe 4949 2,187,513 1/1940 Evans 49-49 X 2,327,366 8/1943 Nampa 4949 X 2,362,912 11/1944 Logan 4949 X 2,735,202 Q/1956 King 4949 X 2,741,849 4/ 1956 Castle 4949 2,984,735 5/1961 Batterson 4949 U X 3,266,013 8/1966 Schmidt 4949 X DENNIS L. TAYLOR, Primary Examiner US. Cl. X.R. 49131

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