RETROREFELCTIVE ROADWAY DELINEATOR BACKGROUND ., The present disclosure relates to a roadway delineator for indicating roadway directional conditions to drivers, capable of being mounted on road structures such as guardrails arranged on either side of a roadway along the roadway. More particularly, it relates to a roadway delineator capable of being mounted on a rail member of a guardrail for reflecting incident light from an oncoming vehicle to indicate roadway directional structures.

Various road structures such as guard rails or wall surfaces in tunnels are generally provided with"delineators"so that observers or vehicle drivers can easily recognize road structures at night. The delineator generally includes a main body with a retroreflective plane that reflects incident light from headlights of an oncoming vehicle back to the vehicle. Up to now, various types of delineators have been proposed, for example, in the following Japanese utility model laid-open publications.

Japanese utility model laid-open publication No. 58-120213 discloses a delineator 901 as illustrated here in Figs. 1A and 1B, having a reflective plane 902 provided on one surface of a main body bent into a triangular shape in profile. The delineator 901 is attached at its fixing portion 903 provided on the bottom thereof to a trough 904 in a rail element 905. The fixing portion 903 is provided at its distal end with aU-shaped cut having a curved recess. The guide marker 901 is fixed to the rail element 905 by inserting a bolt into a hole of the rail element 905 through the cut of the fixing portion 903 located on the hole and then fastening a nut. The delineator 901 illustrated in Figs.

1A and 1B is so designed as to have size that it is wholly fitted in the trough 904 of the rail element 905 without being protruded from the top surface 906 of a longitudinally extending convex buffers 907 of the rail element 905. Accordingly, the length of the retroreflective inclined reflective plane 902 extending along the trough 904 can be

extended by decreasing the oblique angle of the inclined surface. But retroreflectivity is compromised if the oblique angle becomes too small. Further the vertical length of the delineator 901 is limited by the width of the trough 904.

Japanese utility model laid-open publication No. 63-156216 discloses a delineator 901 including a main body bent generally in the form of trapezoid and having a reflective plane formed at the outer portions thereof, as illustrated here in Figs.

2A and 2B. The delineator 910 illustrated in Figs. 2A and 2B has a retroreflective inclined plane 911 similar to that shown in Figs. 1A and 1B and a parallel reflective surface 912 which is generally parallel to the rail element 905. The delineator 910 suffers from the same disadvantages disclosed above with respect to delineator 901.

Japanese utility model laid-open publication No. 58-124514 discloses a delineator 915 as illustrated here in Fig. 3. The delineator 915 comprises a main body including an inclined plate 916 inserted into a trough 904 of a rail element 905 and a front plate 917 covering buffers 907. The delineator 915 is provided on its main body with a reflective article 918 covering an exposed plane facing the roadway. Thus, marker 915 has no retroreflective elements extending beyond top surface 906 of buffers 907. The parallel reflective plane 917 in delineator 915 of Fig. 3 does not reflect the incident light directed thereon at a low angle relative to the front plate back to the light source. Accordingly, the delineator 915 shown in Fig. 3 is small in effective reflective area.

Japanese utility model laid-open publication No. 6-24010 discloses a delineator 919 adapted to be mounted on inner walls of tunnels or guard cables 920 as illustrated in here Fig. 4. The delineator 919 comprises a main body 921 with a T- shaped cross section and a fixing base portion 922 to be attached to the roadway structures such as tunnel inner walls or guard cables. The main body 921 includes a protrusion 923 extending toward the central portion of the roadway and a retroreflective plane 924 provided on the surface of the projection 923. As illustrated

here in Fig. 4, the delineator 919 for mounting on the guard cables 920 has the retroreflective plane 924 protruded beyond the guard cables 920 toward the medial portion of the roadway. Thus, the delineator 919 can be larger and thus more visible than the delineators described above. In order to enhance visibility, the protrusion 923 is extended toward the central portion of the roadway. However, if the protrusion 923 of the delineator 919 is lengthened, it can be damaged when the moving vehicles brush against or near the delineators mounted on the guard cables. Also, the delineators 919 may be damaged during road maintenance, for example, by impact of high pressure water jetted from jet-cleaning vehicles, contact with cleaning brushes of sanitation vehicles, contact with snow blade of snow-removing cars, or the like. Thus, the delineator 919 is generally designed to have a protrusion 923 with a length of not exceeding 50 mm.

Accordingly, there is a need for a roadway delineator easily visible to drivers of oncoming distant vehicles, having a retroreflective medial protrusion plane enlarged in effective reflective area. Further, there is a need for a roadway delineator prevented from damages by contact with moving vehicles or by external forces applied thereto during road maintenance even if the delineator has a medial protrusion with a prominent distance exceeding the design limitation for roadway delineators.

SUMMARY According to the present disclosure, there is provided a delineator with the following construction in order. to solve the above problems.

The delineator according to the present disclosure is adapted to be fixed to a rail element of a guard rail, said guard rail being arranged on either side of a roadway along the roadway and including at least one convex portion relatively swelled towards a medial portion of the roadway and at least one trough relatively caved towards an edge side of the roadway. The delineator comprises a main body adapted to

be fixed to the rail element and including first and second portions extending from the rail element toward the medial portion of the roadway when fixed to the rail element.

The first portion is designed as to be fitted in the trough of the rail element, while the second portion protrudes from the prominent plane of the convex portion of the rail element towards the medial portion of the roadway. The first and second portions each include a retroreflective plane on a surface extending towards an extended direction thereof.

The delineator of the above construction includes a reflective plane provided at its primary portion to be arranged in the trough of the rail element, in addition to a reflective plane with relatively excellent visibility to distant drivers that is provided at the second portion of the rail element. That is, the delineator is provided with a large reflective area by effective use of space in the trough of the rail element and a space around the associated rail element extending from the prominent plane of the convex portion of the rail element towards the roadway. Since the delineator has a retroreflection plane with a large area, it is effectively improved in visibility to distant drivers.

The second portion of the main body includes an elastically deformable polymer. This makes it possible to prevent the second portion extending in the direction of the median line of the roadway from being damaged when any external force is applied to the second portion. The external force applied to the second portion is absorbed by its elastic bending deformation of the second portion.

In another embodiment of the present disclosure, the delineator comprises a main body capable of being fixed to the rail element and including first and second portions extending from the rail element toward the medial portion of the roadway when fixed to the rail element. The first portion is adapted to be located in the trough portion of the guardrail and fixed to a bottom portion of the trough, while the second portion is separated from the first portion and extending from the prominent

plane of the swelled portion of the rail element towards the medial portion of the roadway. At least the second portion is provided with a retroreflective plane a surface extending towards an extended direction thereof and pivotally connected to and elastically forced against the first portion by joining mechanism for allowing the second portion to be turned between a longitudinally extending direction of the rail element and a protruding direction of the body member.

In the above construction, the second portion is pivotally connected to and elastically forced against the first portion so that the second portion is swung between a first position extending in the direction of medial line of the road and a second position parallel to the longitudinally extended rail element. If an external force in the extending direction of road, i. e., if an external force in the direction perpendicular to the prominent surface of the second portion, is applied to the second portion, the second portion is turned in the direction parallel to the rail element. The second portion is returned to its original position, i. e., the position extending in the extended direction of the first portion by the joining mechanism when the external force applied to the second portion is removed. Even if the second portion is extended beyond the design limitation for the roadway delineator, the second portion is effectively prevented form being damaged by the external forces since the force applied thereto by the running vehicles or road maintenance works is absorbed by the joining mechanism. In this case, there is no need to use elastically deformable polymers as a material for the second portion of the main body since the external force applied to the second portion is absorbed by the joining mechanism. Thus, it is possible to use various materials as materials for the first and second portions, which in turn makes it possible to improve the design freedom for first and second portions.

In the embodiment as mentioned above, there is no need to provide a retroreflection plane covering substantially the whole area of the front face of the main body. It is possible to effectively prevent damage of the second portion due to any

external force even if the second portion of the main body is so designed as to have a prominent distance exceeding the design limitation. In other words, it is possible to enlarge the area of effective reflective plane by elongating the prominent distance of the second portion as much as possible. Thus, it is sufficient for the retroreflective plane to cover a part of the whole surface of the main body (in which the second portion is certainly included). Preferably, the retroreflective plane should be so provided as to cover substantially whole surfaces of the main body (i. e., almost whole surfaces of the first and second portions of the main body).

The joining mechanism may be provided on either right face (a face directed to the observer) or rear face (a face opposite to the observer). Preferably, the forcing means is provided on the rear face. In case of that the forcing means is provided on the rear face, it is possible to secure a retroreflective plane having a larger area on the right face as the right face has no the forcing means. Thus, the reflected lights from the retroreflective plane can be recognized with ease by the observers such as drivers on the running vehicles.

The retroreflective plane may be constituted by the first and second portions having retroreflective ability per se. In general, the retroreflective plane is formed by mounting retroreflective members on the first and second portions.

The retroreflective members may be mounted separately on each right face of both the first and second portions. Preferably, the retroreflective plane on the first and second portions of the main body is formed by a single retroreflective member continuously covering the right faces of both the first and second portions. In this case, the retroreflective member is fixed only on the right face of the second portion so that is free from the first portion.

In this case, when the second portion is turned towards the longitudinally extending rail element by any external force, the retroreflective member fixed only on the right face of the second portion is turned along with the second

portion. When the second portion is returned to its original condition, the retroreflective member is returned its original condition along with the second portion.

Since both the first and second portions of the main body are covered with the retroreflective member, it is possible to obtain a retroreflective plane with a large area.

BRIEF DESCRIPTION OF THE DRAWINGS Figs. 1A and 1B are schematic diagrams illustrating a conventional delineator installed on a guard rail; Figs. 2A and 2B are schematic diagrams illustrating another conventional delineator installed on a guard rail.

Fig. 3 is a schematic diagram illustrating another conventional delineator installed on a guard rail.

Fig. 4 is a schematic diagram illustrating another conventional delineator installed on guard ropes.

Fig. 5 is a perspective view illustrating a delineator of the present invention installed on a guard rail.

Fig. 6 is end view of the guard rail on which the delineator of Fig. 5 has been mounted; Fig. 7 is an enlarged fragmentary sectional view of a fixing member used in the delineator of the present invention; Fig. 8 is an enlarged fragmentary sectional view illustrating a delineator fixed on the rail element ; Fig. 9 is a perspective view illustrating a helical spring used as an elastic member in the delineator of the present invention ; Fig. 10 is a fragmentary sectional view illustrating of the main body with the joint mechanism fixed to the rear side of the main body; Fig. 11 is a rear view of the joint mechanism illustrated in Fig. 10 ;

Fig. 12 is a schematic diagram illustrating the delineator installed to the guardrail; Fig. 13 is a schematic diagram illustrating the delineator with the second portion. being swung by an external force applied thereto; Fig. 14 is an end view illustrating a guard rail with a delineator of another embodiment of the present invention mounted thereon; Fig. 15 is an end view illustrating a guard rail with a delineator of still another embodiment of the present invention mounted thereon; Fig. 16 it is an end view illustrating a guard rail with a delineator of another embodiment of the present invention mounted thereon; Fig. 17 is an elevation view illustrating a delineator of a first comparative example; and Fig. 18 is an elevation view illustrating a delineator of a second comparative example.

DESCRIPTION The preferred embodiments of the delineator according to the present invention will be explained below with reference to Figs. 5-18.

A guard rail 4 is disposed as a road structure parallel to and inside an associated roadway and comprises a large number of rail elements 40 with a predetermined length and a large number of posts set in the ground at certain intervals.

The rail elements 40 are previously provided with fasteners composed of a bolt 71 and a nut 72. The rail elements 40 are connected to one another by the fastener to form a rail continuously extending along the direction of traffic on the roadway. As illustrated in Figs. 5 and 6, the rail elements 40 are generally formed of metal sheets such as sheet iron or steel by bending into a generally W-shaped configuration which comprises two convex portions 41 a, 41b relatively protruded toward the roadway, and one trough

portion 42 integrally formed between them and relatively disposed toward the edge side of the roadway. One convex portion 41 a is comprised of a convex end surface 410a and inclined surfaces 430a and 430b. Similarly, the other convex portion 41b is comprised of a, convex end surface 410b and inclined surfaces 430c and 430d. The trough portion 42 is comprised of a bottom surface 420a and inclined surfaces 430b, 430c.

As illustrated in Figs. 5 and 6, a delineator 1 includes a plate main body 11 and a retroreflective member 12 with a retroreflective plane 14. The main body 11 is protruded from the surfaces of the rail element 40 towards the inside of the roadway when fixed to the rail element 40. The main body 11 includes a first portion 111 and a second portion 112. Further, a right face (or a plane facing to drivers of oncoming vehicles) of the main body 11 constitutes a prominent (protruding) surface 110, as illustrated in Figs. 7 and 8.

The first portion 111 is located in the trough portion 42 of the rail element 40 and fixed to the bottom wall 420a of the trough 42. The second portion 112 is protruded from the two convex end surfaces 410a and 410b of convex portions 41a, 41b of the rail element 40 towards the roadway.

As illustrated in Figs. 5 and 6, the first portion has a cross sectional configuration that generally conforms to that of the trough portion 42. This makes it possible to increase an area of the retroreflective plane 14 of the first portion 111 covered with the retroreflective member 12, resulting in effective enhancement of distant visibility.

The second portion 112 of the main body 11 may take various configurations that provide an effective retroreflective plane with a large area.

Preferably, the second portion 112 is so designed as to have a rear edge which conforms to the configurations of the convex end surfaces 410a and 410b of convex portions. 41 a and 41 b of the rail element 40, as illustrated in Figs. 5,6,14 and 15. This

makes it easy to enlarge the effective retroreflective area of the delineator. The second portion 112 may be formed into a symbolic shape. For example, the second portion 112 may be formed into an arrowhead as illustrated in Fig. 15. It is possible to completely cover a whole area of the prominent surface 110 with the retroreflective member 12 by removing marginal parts from the main body 11, as illustrated in Fig. 14.

As illustrated in Fig. 16, the second portion 112 of the main body 11 may have extended portions 118, 119 each being extended beyond an upper or lower edge of the convex end surface 410a or 410b and having a rear edge extending along the inclined surface 430a or 430d connected with the convex portion 41a or 41b of the rail element 40. The provision of such extended portions makes it possible to effectively increase the effective reflective area provided by the second portion 112, without increasing the prominent distance of the second portion 112 protruded towards the roadway.

The main body 11 is set on the rail element 40 at an angle of approximately 90 degrees relative to a longitudinally extending plane of the associated rail element 40. If the angle between the main body 11 and the longitudinally extending plane of the rail element 40 is extremely greater or smaller than 90 degrees, the visibility of the retroreflective plane 14 becomes lowered. For this reason, the angle of the main body 11 relative to the longitudinally extending plane of the rail member is generally determined in the range of 70 to 120 degrees, preferably, in the range of 75 to 110 degrees. The most preferred angle of the main body relative to the longitudinally extending plane of the rail ranges from 80 to 110 degrees.

As illustrated in Figs. 7 and 8, the main body 11 is provided with an L- shaped fixing member 113 at a base portion of the first portion 111 close to the rail element 40. The fixing member 113 is provided with a U-shaped cut (with a curved recess) 115 for attachment to the rail element. In addition, the prominent distance of the second portion 112 of the main body 11 generally ranges from 20 to 50 mm,

through it varies with the width of the roadway with which the delineator 1 is associated. At least the second portion 112 of the main body 11 is made of an elastically deformable polymer. The first portion 111 and second portion 112 are generally formed in one united body with an elastically deformable polymer. For this reason, the main body may absorb any external force (including impacts) applied thereto, thus making it possible to prevent the main body from being broken by the external force.

The elastically deformable polymer may be those such as acrylic resin, polyvinyl chloride resin, polyurethane, polyolefin, acrylonitrile resin, polystyrene, rubber, elastomers and the like. These materials may be used alone or in combination.

Example of commercially available polymers are sold under the trade designation Acrypet available from Mitsubishi Rayon Co., Ltd. under code numbers: IR H-l l, IR H-30, IR H-50.

Preferably, the polymer constituting the main body 11 has a modulus of elasticity in bending within the range of 5000 to 35000 kg/cm2 (approximately 490 to 3430 MPa) to effectively prevent the main body 11 from being broken. In some applications, if the modulus of elasticity in bending becomes too large, the main body encounters difficulty in elastic deformation. In these applications, if the modulus of elasticity in bending becomes too small, there is a fear that the main body 11 cannot be restored to its original shape because of its plastic deformation due to repeated deformation. As a matter of course, this depends on the magnitude of the external force applied to the main body. In case where the main body 11 cannot be restored to its original shape, the angle of the main body, or an angle of the reflective plane 14, relative to the longitudinally extending plane of the rail member 40 is changed, resulting in lowering of distant visibility. From this point of view, the elastic modulus in bending of polymer for the main body 11 preferably ranges from 10,000 to 30,000

kg/cm2 (about 980 to about 2,940 MPa), in particular, from 12,000 to 25,000 kg/cm2 (about 1,180 to about 2,450 MPa).

Other physical properties of polymer for main body 11 can be determined as to effectively prevent the main body 11 from being damaged. For example, the bending strength (measured in conformity with ASTM D790) is generally 100 to 1,500 kg/cm2 (about 10 to about 150 MPa), preferably, 300 or more 1,000 kg/cm2 (about 30 to about 100 MPa). The Izod impact value (measured in conformity with ASTM D256) is generally 1 to 40 kg-cm/cm, and preferably, 1.5 to 20 kg-cm/cm.

Rockwell hardness (measured in conformity with ASTM D785) is usually 25 to 100 and preferred Rockwell hardness is in the range of 30 to 80. Further, when taking account of balance between mechanical strength and elastic bending deformation ability, the thickness of the main body 11 generally ranges from 3 to 10 mm.

The retroreflective member 12 generally includes a retroreflective sheet or retroreflective plate and fixed on the prominent surface 110 of the main body 11 so as to cover almost all the right faces of the first and second portions 111 and 112, except for narrow marginal areas of the prominent surface 110 of the main body 11.

The retroreflective member 12 may be provided on the rear faces of the first and second portions 111 and 112 (a surface opposite to the right surface facing to drivers of oncoming vehicles) in addition to the right face. The retroreflective sheet or retroreflective plate may be solely used as it is. In addition, the retroreflective sheet may be used in a laminated structure by fixing it to other rigid substrate to improve mechanical strength, durability and impact resistance.

The retroreflective sheet may have reflective elements including transparent beads or microprisms such as cube-corner-type prisms. Examples of commercially available retroreflective sheets includes are sold under the trade designations"Diamond Grade reflective sheetings Series 3970"and"Series 981"made by Minnesota Mining and Manufacturing Company of St. Paul, Minnesota,"High

Intensity reflective sheetings, Series 3820"and"Series 580"made by Minnesota Mining and Manufacturing Company, and"Crystal Grade series"made by Nippon Carbide Industries Co. The rigid substrate for attachment of the retroreflective sheet is generally made, of a material having physical properties (impact resistance and flexibility) equal to or substantially equals to the material for the main body 11. There is no limit to a thickness of the rigid substrate, but a preferred thickness ranges from 0.5 to 10 mm to provide an appropriate mechanical strength. The retroreflective sheet is generally fixed to the substrate with a binding agent such as an adhesive.

The retroreflective member 12 may be transparent as a whole. In this case, if the main body 1 fis transparent, the delineator 1 may be recognized by sunlight transmitted through the delineator at dawn or dusk. Further, the retroreflective plane 14 may be provided with self-luminous devices such as electroluminescent elements, LEDs and the like to give the retroreflective plane 14 a self-luminous property in addition to retroreflective ability.

The main body 11 of polymer may be produced by various processes such as machining including cutting and grinding, or molding including injection molding, cast molding or the like. In case where the fixing member 113 is separate from the main body 11, the fixing member 113 is made by cutting of sheet metal or sheet polymer or by molding of polymer.

The retroreflective member 1 is generally fixed the main body 11 with binding agents or fastening screws. In addition, the retroreflective member 12 may be fixed to the main body 11 by fusion bonding of polymer. This may be done, for example, by placing the retroreflective member 11 (retroreflective sheet with or without substrate) on the main body 11 and then applying heat or supersonic wave to their peripheral portions. In this case, it is preferred to bond the retroreflective member 12 to the main body 11 by applying an adhesive agent to the rear side of the retroreflective member 12 to reinforce the adhesion of the retroreflective member 12 to

the main body 11, before fusion bonding between them. This makes it possible to effectively prevent the retroreflective member 12 from being peeled off from the main body even when impact loads are applied to retroreflective member 12 by jet water of high-pressure washing vehicle.

The delineator 1 with the retroreflective member 12 is fastened to the bottom wall 420a of the trough portion 42 of the guard rail 4 by means of various fastening devices such as fastening bolts or screws, as illustrated in Figs. 7 and 8. It is also possible to use fastening bolts for interconnection between two rail elements.

The delineator 1 is fixed to the bottom wall 420a of the trough portion 42 of the guard rail 4 by inserting the leg of fixing member 113 with the U-shaped cut 115 into a gap between a head of bolt 71 and rail element 40, and then fastening the bolt 71 to tightly hold the fixing member 113 between bolt head and rail element 40.

The fixing member 113 may be formed as an integral part of the main body 11 or as a separate member as illustrated. In the latter case, the separate fixing member 113 is fixed to the main body 11 by fastening members such as screws and bolts, or adhesive agents.

There is no limit to a vertically extending length (hereinafter referred to as"vertical length") of the main body 11 when the main body 11 is fixed to the rail element 40 unless the vertical length of the main body 11 neutralizes the effect of the device. For example, the main body 11 may be so designed as to have a vertical length never exceeding the vertical length of rail element 40 ( (i. e., a width of rail element 40)), as illustrated in Figs. 5 and 6. This makes it possible to wholly observe appearance of the rail elements 40. Further, as illustrated in Fig. 14, the main body 11 may have a vertical length exceeding the width of the rail member 40. The visibility of the delineator can be enhanced by increasing the length of the second portion as large as possible. The optimum value for the vertical length of the main body 11 of the

delineator 1 generally ranges from 200 to 700 mm, though it is determined on the basis of the width of the associated rail element or its application.

The second embodiment of the delineator will be explained below with reference to Figs. 7 to 13 illustrating the delineator applied to the guard rail as well as the first embodiment of the present invention.

As illustrated in Figs. 12 and 13, the delineator 1 has a separable structure in which a main body 11 is separated into 2 parts, i. e., a first portion 111 and second portion 112. In normal conditions, the first portion 111 and second portion 112 are arranged in a row so that the main body 11 takes a flat plate form and extends from the rail element 40 towards the roadway, as illustrated in Fig. 12. The front face of the main body 11 protruded from the rail member 40 toward the roadway is a prominent face 110.

The first portion 111 is located in the trough 42 of the rail element 40 and fixed to the bottom wall 420a of the rough 42 in the same manner as that of the first embodiment. Similarly, the second portion 112 is protruded from the prominent surfaces 410a, 410b of the convex portions 41a and 41b of the rail element 40 towards the roadway.

The first portion 111 of the main body 11 is generally formed so that it has a shape similar to the cross section of the trough 42. Alternately, the first portion 111 of the main body 11 may be formed into a rectangular shape slightly smaller than the cross-section of the trough 42, as illustrated in Fig. 14. As described later, the second portion 112 is so constructed as to absorb external forces by its free turn and thus it is very easy to increase an area of the retroreflective plane 14 by increasing the prominent distance in the direction perpendicular to the longitudinally extending surface of the rail element. For this reason, it is relatively free to design the first portion 111 with any desired configuration and size. In other words, the first portion 111 can be formed into a rectangular plate with a relatively small size independently of

shape or size of the rail element 40. This makes it very easy to manufacture delineators with high flexibility of installation. An angle of the main body 11 relative to the longitudinally extending plane of the rail element is generally determined in the range of from 70 to 90 degrees, preferably, in the range of 75 to 110 degrees. The most preferred angle ranges from 80 to 110 degrees.

The main body 11 of the delineator is provided with a fixing member 113 on the side of the first portion 111 close to the rail element 40. The fixing member is fixed to the main body 11 with fastening members such as screws and bolts, or adhesive agents in the same manner as in the first embodiment.

Because of the fact that the main body 11 has a separable construction composed of the first and second portions 111 and 112, there is no limit to a material for the main body 11 and physical properties thereof. The first portion 11 may be made of a relatively hard material including metals such as aluminum, stainless steel, light alloys in addition to polymers mentioned in the first embodiment. Preferably the main body 11 has a thickness of 1 to 20 mm, preferably, 2 to 15 mm, to meet conditions of both mechanical strength and weight saving.

. The main body 11 is provided on its rear side (opposite to the plane facing to drivers of oncoming vehicles) with a joining mechanism 8 (not shown in Figs.

12 and 13). The mechanism 8 comprises a hinge 9 for joining the first and second portions 111 and 112 and allowing the second portion 112 to swing around the first portion 111, and an elastic member 51 associated with the hinge 9 for forcing the second portion 112 to hold its normal condition aligned with the first portion 111.

The second portion 51 is swung around the first portion 111 in the direction parallel to the longitudinally extending plane of the convex portions 41a and 41b by an external force applied to the second portion 112. The elastic member 51 is adapted to force the second portion to swing back to the normal condition perpendicular to the longitudinally extending plane of the convex portions 41a, 41b

when the external force applied to the second portion 112 is removed. To this end, various types of spring such as helical coil springs, leaf springs and the like may be used as the elastic member 51.

, As the hinge 9, there may be used commercially available products generally made of a metal for a hard plastic. It is preferred to use a hinge as illustrated in Fig. 10 and 11. The preferred hinge 9 comprises a first plate 82a with a pair of spaced bearings 8 la, a second plate 82b with a pair of spaced bearings 81b, and a pivot 114 supported by the bearings 81a and 81b. The first plate 82a and the second plate 82b are rotatably connected to one another by bearings 81a, 81b and the pivot 114 made of a metal rod. The helical coil spring 51 is mounted on the pivot 114 and held in a space formed between two bearings 81a of the first plate 82a.

As illustrated in Fig. 9, the helical coil spring 51 serving as the elastic member is made of a metal wire by winding the wire, leaving both ends thereof straight to form legs 512a, 512b. The helical coil spring 51 illustrated in Fig. 9 form are held on the shaft so that an opening angle between legs 512a, 512b is 180 degrees at steady state. If the helical coil spring 51 is compressed so that the angle between two legs thereof becomes smaller than 180 degrees, the helical coil spring 51 produces an elastic restoring force. This restoring force is used for forcing the second portion 112 towards the first portion 111.

The helical coil spring 51 is arranged in the space between two bearings 81 a as previously described above, and their legs 512a, 512b are respectively brought into contact with the back sides of the first and second hinge plates 82a and 82b. In this case, the legs 512a, 512b may be fixed to the first and second hinge plates 82a and 82b. In the embodiment illustrated in the drawings, the legs 512a, 512b are respectively brought into contact with the first and second hinge plates 82a and 82b by the restoring force of the helical coil spring 51. The function of the means 8 composed

of the hinge 9 and the associated helical spring 51 will be described below, making reference to Figs. 12 and 13.

The first portion 111 of the main body 11 is fixed to the trough 42 of the rail element 40 at its one end opposite to the other end joined to the second portion 112 by the hinge 9, while the second portion 112 is extending from the first portion 111 in the direction perpendicular to the longitudinally extending plane of the convex portions 41a, 41b. The pivot (rotating shaft) 114 is located between the first and second portions 111 so that the second portion 112 is allowed to swing around the pivot 114 at the other end of the first portion 111.

The hinge 9 with the helical is coil spring is fixed to the backside (plane opposite to the right plane facing to drivers of oncoming vehicles) of the first portion 111 and second portion 112 by a suitable adhesive agent or fastening members (screws or bolts). The retroreflective member 12 is attached to the body member 11 so-as to cover the right plane facing to drivers of oncoming vehicles and to be directed to the drivers of oncoming vehicles including washing vehicles.

In case where contact with the oncoming vehicle with the delineator or application of jet water, the external force is applied to the second portion 112 in the direction normal to its right plane (i. e., in the direction directed from the right face to the rear face). As a result, the second portion 112 is swung around the pivot 114 in the longitudinally extending direction of the convex portions 41a, 41b so that the main body 11 is deformed into an L-shaped condition as illustrated in Fig. 13. Thereafter, the second portion 112 is swung in the opposite direction by means of the helical spring of the joining mechanism 8 and returned to its original state aligned with the first portion 111.

In Figs. 12 and 13, the retroreflective member I2 covering both the first and second portions 111 and 112 is fixed to not the right face of the first portion 111

but only to the right face of the second portion 112. This results from the fact that manufacturing process of delineator can be simplified.

When providing separately prepared retroreflective members on the right faces of the first and second portions 111 and 112, it is necessary to perform a fixing step twice. In contrast, if the retroreflective member 12 with a size covering both the first and second portions is fixed only on the second portion 112, manufacturing efficiency can be improved. In addition, since such a retroreflective member is a continuous plane free from parting line and gap, it contributes to improve the design.

It is not necessary required to use a separate hinge 9 for the jointing mechanism 8. The first and second portions 111 and 112 may be joined together with a shaft similar to the pivot 114. In this case, the first and second portions 111 and 112 are respectively provided with bearings at their joining portions.

Further, the helical spring 51 may be replaced with a leaf spring. It is also possible to join the first and second portions 111 and 112 together with a film or plate of an elastic polymer such as rubber or elastomer. In the latter case, the film or plate polymer is used as an elastic material and joined together with the pivot 114.

However, it is possible to constitute the joining mechanism having no pivot. For example, the first and second portions 111 and 112 may be joined together by placing an elastic polymer plate or film on the backside of first and second portions 111 and 112 closely arranged side by side, and then fixing it to the first and second portions 111 and 112. Thus, the polymer film or plate serves as the joining means similar to the spring-loaded hinge. In this case, the second portion 112 may be swung around the associated end of the first portion 111, and returned to its original state by the restoring force of the elastic polymer.

In case where the second portion 112 is so designed as to have a prominent distance of less than 50 mm, the whole area of the prominent surface of the

main body 11 is covered with the retroreflective member 12. However, if the second portion 112 is designed so as to have a prominent distance exceeding 50 mm, the retroreflective member may be designed so that the main body is covered with the retroreflective member only on the prominent surface of the second portion 112. The prominent distance of the second portion 112 that extends in the direction of the roadway varies with the width of associated roadway is generally set to less than 150 mm, though it varies with the width of the associated roadway. However, it is possible to enhance the long distance visibility, provided that the prominent distance of the second portion 112 is determined within the range of 20 to 100 mm.

The main body 11 of polymer is produced by cutting a polymer plate of a size greater than the predetermined size into a desired shape of predetermined size, or by molding a polymer material with various moldings processes such as injection or casting into a desired shape of predetermined size. When using a plate metal, the metal plate with size greater than the predetermined size is cut to form a main body with a desired shape and size. In case where the fixing member 113 is separated from the main body 11, the fixing member 113 is also prepared in the same manner.

For the retroreflective member 12, the same material as those disclosed in the first embodiment can be used. The retroreflective member 12 is fixed to the main body 11 in the same manner as the first embodiment mentioned above, by fusion bonding, adhesive agents, or fastening members. Also, the delineator I provided with the retroreflective member 12 is fixed to the bottom surface 420a of the trough 42 of the rail element 40 in the same manner as the first embodiment mentioned above, using a suitable adhesive agent or fastening members such as bolts or screws.

The main body 11 of the delineator 1 is generally designed so as to have a length ranging from 200 to 700 mm as well as that of the first embodiment, though it depends on the width of the associated rail element or its application.

Examples The first example is directed to a delineator 1 according to the first embodiment the present invention.

., Using elastically deformable polymer (Acrypet IR-150), there was prepared a main bodies 11 in the form of a flat plate with a planer front face 110 having a solid construction of first and second portions 111 and 112, as illustrated in Figs. 5 and 6.

The elastically deformable polymer used for main bodies 11 has the following physical properties: Elastic modulus in bending (measured in conformity with ASTM D790): 18000 kg/cm2 (about 1770 MPa) ; Bending strength (measured in conformity with ASTM D790): 660 k g/CM2 (about 65 MPa); Izod impact value (measured in conformity with ASTM D256) : 3.5 kg-cm/cm ; Rockwell hardness (measured in conformity with ASTM D785) is usually 25 to 100 and preferred Rockwell hardness is in the range of 30 to 80.

The main body has a thickness of about 3 mm. The second portion 112 of body 11 has a length of about 350 mm, a width of about 30 mm. The first portion 111 of the main body has a configuration generally corresponding to a shape in cross section of a trough 42 of a rail element 40 as illustrated in Fig. 6. Fixing member 113 was made of an aluminum plate with a thickness of 3 mm and fixed to the rear face of the first portion 111 with two sets of bolts 71 and nuts 72.

A retroreflective sheet sold under the trade designation Diamond Grade No. 3970, made by Minnesota Mining and Manufacturing Company, was fixed approximately all over the front face 110 of the main body 11 with an adhesive agent to prepare a delineator. A retroreflective plane 14 (a surface of the front face 110 of body 11 covered with the retroreflective sheet) has a surface area of about 135 cm2 (about 13500 mm2).

As a comparative example 1, a delineator 1 as illustrated in Fig. 17 was prepared in the same manner as Example 1, except that the retroreflective sheet was attached only on the first portion 111. An area of the retroreflective plane 14 covered with the retroreflective sheet was about 45 cm2 (about 4500 mm2). Similarly, a delineator 1 as illustrated in Fig. 17 was prepared as a comparative sample 2 in the same manner as Example 1, except that the retroreflective sheet was attached only on the second portion 112.

The delineators 1 prepared in Example 1, comparative example 1 and comparative example 2 were respectively fixed to the bottom wall 420a of the trough 42 of rail element 40 in guard rail 4. Although the guard rail 4 was set in the home ground of business establishment for the purpose of experiments, but its specification was the same as the actual guard rail except for the full length.

Night visibility was determined for the delineators 1 respectively prepared in Example 1, comparative example 1 and comparative example 2 in the following manner. That is, the delineator 1 was observed by an observer seated on a seat of a car which brought to a stop at a distance of about 50 m from the delineator in the direction of traffic parallel to the guard rail, using headlights of the car as a source of lights for illuminating the delineator 1.

The delineator 1 of example 1 was considerably superior in visibility to the delineators of comparative examples 1 and 2. Because, the delineator 1 of example 1 is provided with a retroreflective plane on its second body portion extending toward the roadway, in addition to the retroreflective plane provided on the first body portion to ensure a large reflective plane 14. In contrast thereto, the delineator of comparative example 1 possessed poor visibility because of its small retroreflective plane. This results from the facts the delineator of comparative example 1 has the retroreflective plane 14 only on the front face of the first portion and no retroreflective plane 14 is provided on the front face of the second portion. On the other hand, in case of the

delineator of comparative example 2, the retroreflective plane 14 is provided only on the front face of the second portion so that the visibility is not reasonably improved.

The delineator 1 of example 2 was prepared in the following manner: The main body, 11 was prepared in the same manner as in example 1 and then divided into two parts, i. e., a first portion 111 and a second portion 112. The first and second portions 111 and 112 were joined together with a joint mechanism 8 composed of a hinge 9 and a helical spring 51 as illustrated in Figs. 9 to 11. Then, a reflective sheet was fixed to the main body in the same manner as Example 1 to complete a delineator.

The retroreflective member 12 used in the above example 2 is of a laminated structure composed of a retroreflective sheet laminated with a solid substrate made of a polymer. The solid substrate was prepared using the same material as that used for the main body. The retroreflective sheet was the same as that used in example 1.

The retroreflective member 12 was fixed to the body 11 in the following manner. A main body 11 included first and second portions 111 and 112, and polymer substrate having the same shape and size as those of the main body 11.

Then, the substrate was fixed only on the front face of the second portion 112 of the main body 11. The installation of the substrate to the body was carried out by using epoxy adhesive and screw cramp (at five places, i. e., Four Corners and the central part of the second portion). The used screws were of a flat head, so that the front face of the screwed cramped polymer substrate was flat. The substrate was provided on its front face with a retroreflective sheet to cover its entire surface to complete the delineator 1.

The delineator 1 of Example 2 was mounted on the guard rail 4 in the same manner as in Example 1. Absorption capacity for external force of the delineator was evaluated by spraying high-pressure water intensively onto the retroreflective plane 14 of the second portion 112 with a high-pressure washing vehicle. The spraying was carried out under the following conditions:

Water pressure: 80 kg/cm2 Distance between spraying nozzle and reflective plane of the delineator: 30 cm , Time: 1 minute.

During spraying the high-pressure water onto the reflective plane 12, the second portion 112 of the main body 11 was swung around the pivot 114 towards the convex plane 410a, 410b of the rail element 40 so that the main body was folded into an L-shape as illustrated in Fig. 13. This revealed that the delineator has high impact load carrying capacity. After completing the above impact testing, observation of the appearance of the delineator and joint mechanism revealed that there is no abnormality and damage.