MXPA98010657A

MXPA98010657A - Barrier and protection rail for carret

Info

Publication number: MXPA98010657A
Application number: MXPA/A/1998/010657A
Authority: MX
Inventors: S Denman Owen; A Leonhardt Patrick; C Cobb Lincoln; H Oberth Michael; B Welch James
Original assignee: Energy Absorption Systems Inc
Priority date: 1997-12-15
Filing date: 1998-12-14
Publication date: 2000-08-01

Abstract

The present invention relates to a road protection rail including an elongated metal plate forming at least one ridge, the plate includes attenuated regions extending at least partially across the plate and these attenuated regions are oriented obliquely to the longitudinal direction to form at least one elongated bend region in which the plate tends to buckle when subjected to a sufficiently large column load, this fold region being obliquely oriented in the longitudinal direction to push the leading end from the protection rail down into an axial fold, at the front end of the protection rail includes a cable that passes through an opening in the front support post, a split sheave is placed around this cable adjacent to the front support post The split sheave includes the first and second load transfer members that separate easily from each other after the first support post breaks in the opening of an axi impact

Description

BARRIER AND RAIL PROTECTION FOR ROAD BACKGROUND OF THE INVENTION This invention relates to road barriers that include protection rails that extend to the side of a road and to protection rails suitable for use in such a barrier. The patent of E.U.A. 5,407,298 to Sicking and the patent of E.U.A. 5,547,309 from Mak describe road barriers that include grooved protection rails. The protection rails are conventional steel bars that are W-shaped in cross section. Such a protection rail is well adapted to continue steering a car after it has gone off the road, but can provide excessive rigidity against column loads. Such excessive stiffness can result in a tendency of the guard rail to lance a vehicle that collides axially. In order to reduce that tendency, the rail described in the '298 Sicking and' 309 Mak patents includes longitudinally extending slots, which reduce the maximum column load that can be supported by the protection rail. The patent of E.U.A. No. 5,503,495 to Mak describes a cable release mechanism of the protection rail, designed to be used with a support post against road runs. The cable release mechanism includes a plate defining a indented edge parallel to a V-shaped entry to the indentation. This plate is placed between the threaded nut at the end of the barrier cable and the first support post against road accidents. When a support post is broken against an overrun on an axial impact, the cable exits the V-shaped opening gap to uncouple from the release mechanism. A potential problem, associated with the longitudinally grooved guard rail of the '298 Sicking and' 309 Mak patents, is that the longitudinal grooves separate the guardrail by forming four parallel strips. Since the metal plate between the grooves is relatively long and thin, there is little directional control with the direction of flexure of the guard rail in the longitudinal grooves. This creates the possibility that during an impact the protection rail can be bent into an elbow that rises to the height of the vehicle's impact windows. If this were to occur, there would be an increased danger that the guardrail could penetrate through the windows into the vehicle occupant compartment, continuously interacting with the installation of the guard rail. A potential problem associated with the cable release mechanism of the '495 Mak' patent protection rail is the grooved support plate could not be released as quickly as desired, when a support post is broken against hitting in an impact axial, particularly if the support post can be broken at an oblique angle to the horizontal.

BRIEF DESCRIPTION OF THE INVENTION The present invention is defined with the following claims and nothing in this section should be considered as a limitation on those claims. As an introduction, the preferred embodiments described below include a road protection rail having attenuated regions, such as grooves, holes, thinned regions, ridges or teeth that are oriented obliquely to the longitudinal direction of the guard rail. These attenuated regions form one or more elongated bend regions in which the protection rail tends to progressively buckle when a sufficiently large column load is applied, such as when released by a vehicle impacting axially. The fold regions are oriented obliquely to the longitudinal direction of the guard rail, such that the rear portion of the guard rail has a reduced tendency to move towards up as the protection rail buckles. The protection rail is secured by a tension member (such as a cable) or a support post. The first and second load transfer members form a split sheave that is interposed between an enlarged portion of the tension member and the support post. These load transfer members extend to opposite sides of the tension member and are positioned to prevent the enlarged portion of the tension member from passing between the load transfer members. The load transfer members are easily separated from one another to release the tension member after the support post breaks on an axial impact.

BRIEF DESCRIPTION OF THE DRAWINGS Figures 1, 2 and 3 are isometric, vertical and plan views, respectively, of a road barrier incorporating the presently preferred embodiments of the present invention. Figure 4 is a vertical view of the most front plate of the protection rail of the embodiment of Figures 1 to 3, before assembly. Figure 5 is a vertical view of the protection rail plate which is arranged immediately behind the protection rail plate of figure 4 in the embodiment of figures 1 to 3, before assembly. Figure 6 is an isometric view of a support post suitable for use in the front portion of the embodiment of Figures 1 to 3. Figure 7 is an isometric view of a support post suitable for use behind the post of support of figure 6 in the embodiment of figures 1 to 3. Figure 8 is a fragmentary perspective view showing the front support post of the embodiment of figures 1 to 3. Figure 9 is an isometric view of one of the transfer members of Figure 8. Figures 10 to 14 are isometric views of alternate modalities of attenuated regions suitable for defining a bend region in regions of the protection rail of alternative modes. Figure 15 is an isometric view of a section of a protection rail that includes attenuated regions to define two fold regions.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Returning to the drawings, figures 1 to 3 use various views of a road barrier 10 incorporating the preferred embodiments of this invention. The barrier 10 includes a protection rail 12 constituted by a plurality of plates 14, 16 and 18 of the protection rail. The plates 14, 16, 18 of the protection rail are sufficiently rigid to deflect a motor vehicle in many cases. For example, the plates 14, 16, 18 on the protection rail may be formed by a steel bar W of measure 12 and the bar in W may be configured as defined in specification M18D-89, class A, type 3 , from AASHTO. The protection rail 12 is supported above ground level by support posts including the front support posts 20 and the intermediate support posts 22. As best shown in Figure 3, the road barrier 10 is placed beside a road R and includes an end section 24 that is damped to reduce any tenure of the road barrier 10 to lance an impacting vehicle, which travels in the longitudinal direction L. As shown in figure 3 , the front section 32 of the road barrier 10 is bent away from the road R. A strut 26 is placed between the front support posts 20 in the conventional manner. A tension member, such as a cable 28, is secured to plate 14 of the protection rail, between the front support posts 20. The front end of this cable 28 passes through an opening in the front support post 20 as It is described below. Figure 4 is a vertical view of a plate 14 of the protection rail. In Figure 4, the front portion of the plate 14 of the protection rail that supports the end section 24 is positioned to the left. An arrangement of holes 42 is formed in the forward end of the plate 14 of the protection rail to receive bolts (not shown in Figure 4) that secure the plate 14 of the protection rail and the end section 24. The holes 44 are provided to secure a fastening plate (not shown in Figure 4) that engages with the rear end of the cable 28 (not shown 'in Figure 4) in the conventional manner. The back holes 46 allow the plate 14 of the protection rail to be bolted to the plate 16 of the protection rail of Figures 1 to 3. The longitudinally extending slots 40 are provided to attenuate the plate 14 of the protection rail. and to arrange for buckling of the column when subjected to considerable column loads in an axial impact. In this modality, the slots 40 are approximately 19 by 178 mm, and are centered in the valley and on the crests of the plate 14 of the protection rail. The slots 40 can be replaced by other means, to prevent the plate 14 from launching an impacting vehicle, such as an array of openings, for example. Figure 5 shows a vertical view of the plate 16 of the protection rail. The plate 16 includes the front and rear holes 50, 52 positioned to receive, the fasteners securing the plate 16 the protection rail to the plates 14 and 18, respectively. The plate 16 of the protection rail also includes the attenuated regions 34 that form a fold region 56 oriented obliquely with respect to the longitudinal direction L. In the embodiment of Figure 5, the attenuated regions 54 are formed by recesses placed on the edges. of plate 16 of the protection rail. These recesses are staggered along the length of the plate 16 of the protection rail and are positioned along the fold axis A which is oriented obliquely at an angle de of about 30 ° C, with respect to the longitudinal direction L of plate 16 of the protection rail. The first and second portions 58, 60 of the plate 16 of the protection rail are positioned forwards and backwards of the fold axis A, respectively. Since the lower attenuated region 54 is positioned forward in the attenuated upper region 54, the second portion 60 tends to move downward, when the plate 16 of the protection rail is bent with the extreme axial load associated with an impacting vehicle. axially. In this way, the road barrier 10 is provided with a preferred fold or fold direction, which has been designed to maintain the fold region 56 of the guard rail plate 16 near the ground and to help control the life of the barrier. displacement of the vehicle that makes impact decelerated, according to the bar 16 for road responds to the impact. In the embodiment of FIG. 1, protective example 12 is secured to the support posts 20, 22 only the first, fifth and tenth support posts, counted from the end section 24. The attenuated regions 54 are preferably positioned between the posts 6 and 7 and optionally between the posts 6 and 4. Figure 6 shows an isometric figure of one of the front posts 20 suitable for use in the first and second positions of the road barrier 10. Each front support post 20 includes a slot 70 and a transverse hole 72. In this embodiment, the slot is approximately 10 mm in width and 610 mm in length, and the hole 72 is approximately 61 mm in diameter. Each front support post 2o is preferably formed of wood and the slot 70 is provided to reduce the force required to break the post 20 of the hole 72 in an axial impact. Figure 7 shows an isometric view of one of the intermediate support posts 22 which in this embodiment are also made of wood and are used in positions 3 to 11, counted from the front part of the road wall 10. Each intermediate support post 22 includes two holes 34 that are approximately 51 mm in diameter. Figures 8 and 9 provide further details with respect to the manner in which the front end of the shift 28 is secured to the first front support post 20. As shown in Figure 8, the forward end of the cable 28 includes a threaded end 80 which receives a nut 82 and a sheave 84. The nut 82 and the sheave 84 copra to form an enlarged portion of the cable 28 having a first area. In alternative embodiments, the enlarged portion may be forged in stamp or otherwise permanently molded on the end of the cable.28, or releasably secured thereto. A glass sheave 86 is interposed between the sheave 84 and the post. This split sheave 86 is formed by two load transfer members 88 having a combined cross-sectional area adjacent to the post 20 which is greater than the first area of the sheave 84. In this way, the load transfer means 88 perform a load diffusion function. As best shown in Figure 9, each of the load transfer members 88 includes a first part 90 that is located next to the post 20 and a second part 92 divided to fit the hole 72 (Figure 8) . The first and second parts, 90, 92 preferably define a nib 93 to partially receive the cable. As shown in Fig. 8, each of the load transfer members is literally placed on a respective side of the vertical plane passing behind the center of the cable 28 and the gap between the load transfer members 88 is preferably oriented in vertical direction. From a sufficiently severe axial impact, the impacting vehicle will break the support post in the hole 72. This will allow the load transfer means 88 to move away from each other, thereby releasing the threaded end 80 of the cable 28, including the nut 82 and the sheave 84. The attenuated regions described above can choose many alternative forms, as shown in figures 10 and 14. Each of these figures shows an isometric view of an alternative form of the plate 16 of the protection rail and in each case the bending axis is indicated above reference A. In figures 10-14, the front part of the plate 16 of the protection rail is on the left and the attenuated regions are near the front end of the plate 16 In the embodiment of figure 10, the attenuated regions are formed by the circular holes. Since the circular holes 100 are formed on the uppermost portion of the ridge and the lowermost portion of the central bath, they will not appear colonial from the isometric view of Figure 10, but would appear colonial in the vertical view. In the embodiments of Figures 11 and 12, the attenuated regions are formed by the slot 102 and the non-circular holes 104, respectively. As shown in Figure 13, the attenuated regions may be formed by one or more ridges 106 and in Figure 14 the attenuated regions are formed by a combination of hole 108 and flange 110. In alternative embodiments, the attenuated regions may correspond to thinned regions of the protection rail plate. Many changes and modifications can be made to the preferred embodiments described above. For example, this invention is not limited to the use with W defining two ridges extending longitudinally of the bar. Rather, this invention may be adapted for use with a wider variety of guard rail plates, including those having one, two, three or more ridges that extend longitudinally, as well as box sections. Due to the tension the cable shape illustrated above is not limited; rather, any suitable structure can be used to transmit stress loads, including metal plates, rods, chains and the like. The load transfer means may be configured differently than as illustrated and the second part 92 may be drawn deeper into the opening 72. If desired, the nicks 93 may be removed in the first and second parts 90, 92 The edges can be formed of any suitable material. The bend region does not have to be configured as a straight line and can be positioned and configured as appropriate for the particular application. The fold region can be defined by attenuated regions of similes. For example, a bend region may be defined for combination of a circular hole, a non-circular hole and a flange. In alternative applications, the attenuated regions can be partially or completely extended through the section of the protection rail. The attenuated regions may be oriented in other oblique (not perpendicular) directions with respect to the longitudinal direction, such as 45 ° for example. A plurality of attenuated regions may also be expanded to provide controlled bending of the guard rail plate. For example, Figure 15 shows a figure of a plate 16 of the protection rail on which two bending axes, A and B, are defined by perforations of the guard rail plate added along the bending axes when Observe vertically. By appropriately placing one or more regions in bending and through the adjustments of the angles of the bending axes thus created, the time regulation and the response magnitude of the fold of the protection rail plate can be adjusted for particular applications as along the road The protective rail plates described above can be used in a wide variety of barriers, including simple protective rail barriers, converging guard rail barriers and energy absorbing barriers. Although shown in use on a front portion of a guard rail barrier, these guard rail plates can be used at any desired point along the barrier of the guard rail. Similarly, the load transfer means of support posts other than the forwardmost pole illustrated can be used. As used herein, the term "set" of elements is illustrated in general terms in one more global elements. The present detailed description has described only a few of the many forms that can be chosen by this invention. For that reason, it is intended that this detailed description be considered as illustrative and not as limiting. It is only the following claims, including all equivalents, which are intended to define the scope of the invention.

Claims

NOVELTY OF THE INVENTION CLAIMS

1. - A protective rail (12) for road comprising an elongated metal plate (16), said plate (16) forming at least one ridge extending along a longitudinal dimension and having a rigidity adapted to deflect an automobile that has left the road, said plate (16) comprising a set of attenuated regions (54) extending at least partially through the plate (169, said regions being oriented obliquely to the longitudinal direction (L ) to form an elongated fold region (56) in which the plate (16) tends to buckle when subjected to a sufficiently large column load, said bend region (56) being obliquely oriented to the longitudinal direction (L

2. A road barrier (10) comprising a protection rail according to claim 1 and installed on the side of the road, said barrier (10) comprising: a plurality of support posts (20, 2). 2) comprising a first support post (20), said first support post defining an opening (62) therethrough; a protection rail (12) supported above the ground level by the support posts (20, 22), said protection rail (12) comprising the metal plate (16) defined by claim 1, in such a way that the The back portion of the protection rail (12) has a reduced tendency to move upwards when the plate (16) is bent along the fold region (569 on the axial impact, a tension member (28) secured to one of the protection rails (14) and passing through the opening (72) in the first support post (20), said tension member (28) comprising an enlarged portion (82, 84) near the first post of support (20); and first and second load transfer members (88) interposed between the enlarged portion (82, 84) and the first support post (20), said load transfer members (88) extending to opposite sides. of the tension member (28) and placed to prevent the enlarged portion (82, 84 ) pass between the load transfer members (88) easily separating said load transfer members (88) from each other after said first support post (20) breaks in the opening (72).

3. The invention according to claim 1 or 2, further characterized in that said plate (16) comprises at least two sets of attenuated regions (100), each set extending at least partially through the plate (16) , said attenuated regions (100) being oriented in each set obliquely to the longitudinal direction (L) to form a plurality of elongated bend regions in which the plate (16) tends to buckle when subjected to a sufficient column load. large, said bending regions being oriented obliquely to the longitudinal direction.

4. - The invention according to claim 1 or 2 or 3, further characterized in that the attenuated regions (54) comprises at least one opening (100, 102, 104) in the plate (16).

5. The invention according to claim 1 or 2 or 3, further characterized in that the attenuated regions (54) comprises at least one region thinned in the plate (16).

6. - The invention according to claim 1 or 2 or 3, further characterized in that the attenuated regions (54) comprise at least one toothed region (106) in the plate (16).

7. - The invention in accordance with the claim 1 or 2 or 3, further characterized in that the plate (16) forms two parallel ridges.

8. A barrier (10) for road comprising a protection rail according to claim 1, further characterized in that said protection rail is oriented on the road barrier, such that the first portion (58) of the plate (16) is located forward of a second portion (60) of plate (16) in an anticipated direction of axial impact, because the fold region (56) is between the first and second portions (58, 60) of the plate (16) and because the fold region (56) is oriented to reduce any tendency of the bend region (56) to rise when the plate (16) is bent along the fold region (56) at the axial impact.

9. - The road barrier according to claim 8, further characterized in that the road barrier (10) comprises a front section (32) and that the front section (32) with each protection rail in accordance with claim 1

10. A road barrier (10) comprising: a plurality of support posts (20, 22) comprising a first support post (20) and a first support post (20) defining an opening (72). ) through it; a protection rail (12) supported above the ground level by the support posts (20, 22); a tension member (28) securing the protection rail (12) and passing through the opening (72) in the first support post (20), said tension member (28) comprising an enlarged portion (82; 84) near the first support post (20); and first and second load transfer members (88) interposed between the enlarged portion (82, 84) and the first support post (20), said load transfer members (88) extending to opposite sides of the tension member ( 28) and being positioned to prevent the enlarged portion (82, 84) from passing between the load transfer members (88), said load transfer members (88) easily separating from each other after the first support post (20) breaks in the opening (72).

11. The invention according to claim 2 or 10, further characterized in that the protection rail (12) further comprises a plurality of longitudinally extending grooves (40), which extend therethrough, reducing said grooves (11). 40) and the column resistance of the protection rail (12).

12. - The invention according to claim 2 or 10, further characterized in that each of the load transfer members (88) comprises a first part (90) which is located next to the first support post (20) and a second part (92) after an opening (72) in the first support post (20).

13. - The invention according to claim 10, further characterized in that the protection rail (12) comprises an attenuated portion (54), said attenuated portion (54) reducing the column resistance of the protection rail (12).

14. - The invention according to claim 2 or 10, further characterized in that each of the first and second load transfer members (88) is arranged entirely on a respective side of a plane passing through the opening ( 72) on the first support post (20).

15. The invention according to claim 2 or 10, further characterized in that the first and second load transfer members (88) comprise to form a measuring sheave (86).

16. - The invention according to claim 2 or 10, further characterized in that the first and second load transfer members (88) define a first cross-sectional area to the opening (72) in the first support post (20), because the enlarged portion (82, 84) defines a second cross-sectional area to the opening (72) in the first support post (20) and because the first area is greater than the second area, such that the transfer members of load (88) perform a load extension function.

17. The invention according to claim 2 or 10, further characterized in that the load transfer members (88) are operative to separate from each other after the first support post (20) breaks in the opening ( 72) of an axial impact, thus accelerating the libration of the tension member of the first support post.