FIELD OF THE INVENTION

This invention relates generally to delineators that are used to control vehicle traffic on roadways and the like. The invention also relates to associated articles, systems, and methods.

BACKGROUND

Traffic delineators are known. Delineators are typically used on or near roadways or other paved or unpaved surfaces where automobiles, trucks, or other motorized or unmotorized vehicles travel. Often a series of delineators are arranged along a road, lane, or path so as to highlight or increase its visibility for the benefit of vehicle operators. FIG. 1 is an idealized perspective view of a roadway 110 along which delineators 112 have been placed to mark the path or direction of the roadway. Delineators can also be used in construction work zones to help guide vehicles along rerouted paths that may be unfamiliar to the vehicle operators. Perhaps because delineators can be used to direct or "channel" traffic in a given direction, they are sometimes also referred to as channelizers.

In some cases, delineators may be used in applications where visibility from only one direction is considered important. In other cases, e.g., when placed between lanes of traffic that move in opposite directions, it may be important for the delineator to exhibit high visibility from both such directions. In still other cases, such as at intersections, it may be important for the delineator to exhibit high visibility from four or more different directions, e.g., north, south, east, and west.

An example of a known delineator design is simply a post attached to a base. For improved visibility, the post may comprise high visibility materials. For daytime visibility, the post may be fabricated from bright diffuse materials, such as white or orange paint. For nighttime visibility, retroreflective sheeting may be wrapped around a portion of the post. Retroreflective sheeting has the characteristic of directing incident light back in the general direction from which it came, regardless of the angle at which the light impinges on the surface of the sheeting. Thus, as a vehicle approaches a roadway sign or other structure on which a retroreflective sheet is mounted, light from a vehicle headlamp may impinge on the sheeting, which then reflects the light back in the general direction of the headlamp. The retroreflection occurs in a small but finite angular cone, which cone encompasses the eye of the vehicle operator so that the operator perceives the sign as being conspicuously bright and highly visible.

FIGS. 2 and 3 are provided for background purposes to exemplify two angles that may have some significance when discussing retroreflective sheeting, or other reflective sheeting. FIG. 2 is a top view of a vehicle 210 traveling in a direction 212 along a roadway 214. Reflective sheeting 216 is provided near the side of the road. Sheeting 216 is assumed to be flat and planar, and the axis 218 is perpendicular to the plane of the sheeting. (In cases where the reflective sheeting is not flat, each portion of the sheeting may be considered to be flat if the size of the portion is small enough.) Axis 220

represents the direction along which light from the vehicle headlamp impinges upon the sheeting 216. The angle β between the axes 218 and 220 is referred to as the entrance angle for the light. A side view of this situation is shown in FIG. 3, where the vehicle headlamp (or other light source) is shown separately and labeled as 310, and the eye of the vehicle operator (or other observer) is shown separately and labeled 312. An axis 314 extends directed between the headlamp 310 and the sheeting 216. Another axis 316 extends between the sheeting 216 and the observer 312. The angle a between the axes 314, 316 is referred to as the observation angle.

Some delineators are designed to be oriented in an upright position but are not designed to withstand an impact from a moving vehicle. If an automobile or other vehicle collides with or runs over such a delineator, the delineator will break or bend, but it will typically not return to its upright position. Such a delineator may be completely acceptable for applications in which the delineator will be mounted a significant distance from lanes of traffic, or where the delineator will be mounted atop a Jersey barrier or similar structure.

Other delineators are designed to be oriented in an upright position, and are also designed to withstand an impact from a moving vehicle. If an automobile or other vehicle collides with or runs over such a delineator, the delineator "bounces back" or otherwise restores itself to a substantially upright position. These delineators may be referred to as self-uprighting delineators. BRIEF SUMMARY

Many of the designs for self-uprighting delineators use complex mechanisms involving bellows, springs, cables, or the like. We have developed a design feature for delineators that can, in at least some cases, be used to provide self-uprighting delineators of simplified and robust construction.

The present application therefore discloses, among other things, traffic delineators that include a tubular body and a transversely slotted region that enhances flexing of the tubular body in response to vehicle impacts. The tubular body has first and second ends, the first end being configured as a base or being adapted for affixing to a base. The slotted region includes one or more slots formed transversely in the tubular body. In some embodiments, the one or more slots may include one or more discrete slot, each of which may define a hinged section of the tubular body. In some embodiments, the one or more slots may include at least one continuous transverse slot having a helical configuration. In any case, the slotted region may be disposed proximate the first end of the tubular body. In some embodiments a second slotted region or other window region may be provided, and disposed elsewhere on the tubular body so as to expose a refiective sheet that may be applied to an inner core disposed within the tubular body.

Related methods, systems, and articles are also discussed.

These and other aspects of the present application will be apparent from the detailed description below. In no event, however, should the above summaries be construed as limitations on the claimed subject matter, which subject matter is defined solely by the attached claims, as may be amended during prosecution.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a perspective view of a roadway with delineators positioned along the roadway;

FIG. 2 is a top view of a vehicle on a roadway encountering a reflective sheet; FIG. 3 is a schematic side view of selected elements of the arrangement depicted in

FIG. 2;

FIG. 4 is a schematic elevational view of a delineator having a transversely slotted region;

FIGS. 4a and 4b are enlarged views of a portion of the delineator of FIG. 4; FIGS. 4c and 4d are schematic sectional views taken along lines 4c-4c and 4d-4d in FIG. 4b;

FIG. 5 is a schematic elevational view of a portion of the delineator of FIG. 4 when a lateral bending force is applied to the delineator;

FIGS. 6-8 are schematic elevational views of portions of alternative delineators, each of which incorporates a transversely slotted region;

FIG. 9 is an exploded perspective view of an exemplary delineator incorporating two transversely slotted regions;

FIG. 10 is a schematic perspective view of another exemplary delineator;

FIGS. 1 la-c depict in schematic elevational view portions of delineators that include a narrowing feature;

FIGS. 12a-e are schematic views of some shapes that can be used for the cross- sectional shape of the tubular body of the disclosed delineators; and

FIG. 13 is an exploded elevational view of a delineator having a core/shell construction.

In the figures, like reference numerals designate like elements.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

In FIG. 4, we see a schematic elevational view of a delineator 410 that incorporates a slotted region 416. The delineator 410 includes a tubular body 412 having a first end 412a and a second end 412b, and a base 414. For reference purposes, a Cartesian x-y-z coordinate system is also included in the figure. A delineator axis 413, which is parallel to the z-axis, defines the longitudinal axis of the delineator.

The first end 412a of the body 412 is shown as being adapted to fit tightly within an opening of the base 414. Alternatively, the end 412a can itself be configured as a base. The base, which can be of any known design, has a sufficient weight and/or is provided with sufficient attachment mechanism(s) to the pavement or ground so as to keep the delineator in an upright position after installation. In some cases, the base may be integrally formed with the tubular body, while in other cases the base may be press-fit, adhered, or otherwise permanently, semi-permanently, or releasably attached to the body 412. If the delineator is not omnidirectional, i.e., if it is designed to have one or more preferred viewing orientation, then the base 414 may be provided with a distinctive shape, marking, or other alignment feature that indicates to an installer how to properly orient the delineator relative to the direction of traffic or another characteristic of the surroundings.

In exemplary embodiments, the delineator 410 may comprise high visibility materials and components. For example, the tubular body may be made of a brightly colored (e.g., white, orange, or other color) polymer or other suitable material, or brightly colored paints or other substances, including fluorescent materials or films, may be applied to the body for enhanced visibility. In FIG. 4, three reflective sheets 422a, 422b, 422c are shown attached to an outer surface of the body 412, but more or fewer sheets (including no reflective sheets) can also be used. One, some, or all of these sheets may provide high daytime visibility, and/or high nighttime visibility. Sheeting that is retroreflective can provide high nighttime visibility. Retroreflective sheeting can be characterized by the sheeting's coefficient of retroreflectivity, which is typically measured in units of candelas per lux per square meter, or cd/(lux*m ² ). Retroreflective sheeting may in some cases have a retroreflective coefficient of at least 10, or at least 100, or at least 500 cd/(lux*m ² ) for head-on viewing (β = 0), but the retroreflectivity may decrease or otherwise change with increasing entrance angle. The amount of decrease as a function of entrance angle depends on design details of the retroreflective sheeting. Although retroreflective sheeting from any vendor may be used, retroreflective sheeting sold by 3M Company is preferred. Such sheeting may include 3M™ Diamond Grade™ DG ³

Reflective Sheeting Series 4000, 3M™ Diamond Grade™ Conspicuity Markings Series 983, and/or 3M™ Diamond Grade™ Flexible Prismatic School Bus Markings Series 973, for example.

The reflective sheets 422a, 422b, 422c may be wrapped around the entire circumference of the body 412, or they may be applied to only a portion of the

circumference. If they are wrapped around the entire circumference, the delineator may be said to be omnidirectional, since the delineator maintains high visibility for all viewing directions in or near the x-y (horizontal) plane. Alternatively, one or more of the sheets 422a, 422b, 442c may be applied to only a portion of the circumference of the body 412, such that high visibility is provided along only one viewing direction or range of viewing directions (unidirectional delineator), or along only two distinct viewing directions or ranges of viewing directions (bidirectional delineator), for example. Significantly, the delineator is provided with a slotted region 416 which includes at least one transverse slot. In the embodiment of FIG. 4, four discrete transverse slots 418a, 418b, 418c, 418d are provided, but in other embodiments any other number of slots may be used as desired. The slots 418a, 418b, 418c, 418d, which may be referred to collectively as slots 418, are arranged in an alternating fashion on opposite sides of the body 412 and are arranged with a uniform spacing. In alternative embodiments, transverse slots may be provided in more than two sides or in only one side of the tubular body, and the slots may be arranged to have a non-uniform spacing. The slots 418 are shown as being inclined at a particular angle relative to the x-y plane, but other angles of inclination, including zero inclination, may also be used. Some of these design details are discussed later in connection with FIGS. 4a-d.

By selectively removing or otherwise omitting material from the tubular body 412 in the form of the transverse slots, remaining portions of the body 412 become easier to move and flex. For example, each of the discrete transverse slots 418 allows a portion of the body 412 proximate the slot to flex in a manner analogous to a hinge or cantilever, the amount of flexing being dependent on material properties of the body and on the slot gap (or width), the slot depth, and other slot geometry. Each transverse slot 418 can thus be said to produce a corresponding hinged section, the hinged sections being indicated in FIG. 4 generally at 420a, 420b, 420c, 420d, and collectively referred to as hinged sections 420.

FIGS. 4a and 4b are enlarged views of the portion of delineator 410 in the vicinity of the slotted region 416. FIGS. 4c and 4d are schematic sectional views taken along lines 4c-4c and 4d-4d, respectively, in FIG. 4b. Collectively, these FIGS. 4a-d identify the following design features or parameters:

• pi, p2, p3, and p4, which represent approximate pivot points or pivot axes of the hinged sections.

• γ, which represents the angle of inclination of the slots.

• sOl, which represents the vertical distance (along the z-axis or longitudinal axis

413 of the delineator) from the base of the delineator to the lowest slot on the left hand side, and s02 is the analogous parameter for the lowest slot on the right hand side. • sl, which represents the vertical distance between adjacent slots on the left hand side, and s2 represents the analogous parameter for adjacent slots on the right hand side.

• wl, which represents the width (or gap dimension) of the left-side slots as

measured along the z-axis, and w2 represents the analogous parameter for the right-side slots.

• wl ', which represents the width of the left-side slots as measured along an axis perpendicular to the slots, and w2' represents the analogous parameter for the right-side slots.

• dl, which represents the depth of the left- side slots as measured along the x-axis

(perpendicular to the z- or delineator longitudinal axis), and d2 represents the analogous parameter for the right-side slots.

• t, which represents the wall thickness of the tubular body 412 of the delineator.

• D, which represents the outer diameter of the tubular body. Note that the

tubular body as depicted in FIGS. 4c-4d has a circular cross-sectional shape. For non-circular shapes, the outer diameter D can be considered to be the maximum transverse dimension of the cross-sectional shape. Alternatively, in some cases the outer diameter D for non-circular cross-sectional shapes may be considered to be the transverse dimension of the shape of the tubular body in the horizontal plane in the vicinity of the slot, measured along an axis associated with the direction of the slot as projected in the horizontal plane. For example, for the slots depicted in FIGS. 4c and 4d, the axis associated with the direction of the slot as projected in the horizontal plane is an axis parallel to the x-axis.

These design features and parameters, in addition to the total number of discrete transverse slots and their placement along the circumference of the tubular body or the azimuthal angle Θ (as measured relative to the x-axis or relative to some other desired reference direction associated with the delineator, see generally FIG. 4c), may be selected as desired to provide a multitude of different designs for the slotted region. The reader will also understand that a plurality of different slotted regions may be provided in a given tubular body, if desired. Without wishing to be limited, in embodiments such as that shown in FIGS. 4a-d, it may be desirable to specify that wl ' ~ w2', and that S I ~ S2.

In the embodiment of FIGS. 4a-d, the transverse slots are oriented such that the pivot axes pl-p4 of the hinged sections 420a-d, respectively, are all substantially parallel to each other and to the y-axis. Such a relationship provides a delineator that has an azimuthally asymmetric bending property. In particular, the delineator 410 preferentially bends in the x-z plane (azimuthal angles of Θ = 0 and 180 degrees), rather than in the y-z plane (azimuthal angles of Θ = 90 and 270 degrees). If the delineator were redesigned so that pivot axes of the hinged sections were all aligned with the x-axis, then the delineator would preferentially bend in the y-z plane rather than in the x-z plane. In another embodiment, the delineator can be provided with some (e.g. , half) of the discrete transverse slots arranged to provide pivot axes parallel to the y-axis, and the remainder (e.g. , half) of the discrete transverse slots arranged to provide pivot axes parallel to the x- axis. Such a delineator has two preferred bending planes, namely, the x-z plane and the y- z plane. The reader will understand that these design principles can be extended to provide slotted regions that exhibit preferential bending in only one plane, or in exactly two planes, or in any other number of planes.

These design principles may be important depending on the desired properties of a particular delineator. For example, if a delineator is intended to be mounted close to vehicle traffic that moves along a particular direction of traffic, the delineator may be provided with a slotted region characterized by a preferred bending plane that is oriented parallel to the direction of traffic. Such preferred bending plane may be the only preferred bending plane associated with such slotted region, or it may be one of multiple preferred bending planes. If the delineator is omnidirectional or bidirectional, such that reflective sheeting is exposed on only one side or on only two sides of the delineator, the one or two directions of enhanced visibility may be configured to have a specific orientation relative to the preferred bending plane. For example, the one (omnidirectional) or two

(bidirectional) directions of enhanced visibility may be configured to be substantially aligned with the preferred bending plane. Other orientations and relationships between direction(s) of enhanced visibility, direction(s) of enhanced bending, and/or direction(s) of traffic are also contemplated. Turning now to FIG. 5, we see there a schematic elevational view of a portion of the delineator of FIG. 4 when a lateral bending force is applied to the delineator. The bending force, which may be applied by a vehicle that has impacted the delineator, may be applied to a portion of the tubular body 412 above the slotted region 416. The view of FIG. 5 demonstrates how some transverse slots may become wider, and some may become narrower, depending on the azimuthal direction of the applied force. In order to reduce stress and avoid cracking or other failure of the wall of the tubular body in the hinged sections, the cusps (terminuses) of each transverse slot may optionally be designed to have a continuously rounded shape with no sharp angles or points at which stress could exceed material breaking points. In exemplary embodiments, the design details of the slotted region 416 and of the remainder of the delineator allow the delineator to withstand bending angles φ of at least 90 degrees and to withstand being run over by a vehicle. In such cases the delineator may be of the self-uprighting type, so that it readily returns to its original vertical orientation.

FIGS. 6-8 are schematic elevational views of portions of alternative delineators, each of which incorporates a transversely slotted region. In FIG. 6, a delineator 610 comprises a tubular body 612 having a first end 612a configured as a base or being adapted for affixing to a base. A slotted region 616 is provided in the tubular body, the slotted region comprising four discrete transverse slots 618a-d which form four hinged sections 620a-d respectively. Slots 618a, 618c are provided on one side of the body 612, and slots 618b, 618d are provided on an opposite side of the body, resulting in a design having a preferred bending plane in the x-z plane. The diameter of the body 612 (see discussion above with regard to diameter for circular and non-circular cross sectional shapes) is D. The depths dl and d2 of the slots are each greater than D/2, and dl + d2 > D. If desired, dl ~ d2. Unlike the slotted region 416, the transverse slots of region 616 are oriented at an inclination angle γ = 0.

In FIG. 7, a delineator 710 comprises a tubular body 712 having a first end 712a configured as a base or being adapted for affixing to a base. A slotted region 716 is provided in the tubular body, the slotted region comprising four discrete transverse slots 718a-d which form four hinged sections 720a-d respectively. Slots 718a, 718c are provided on one side of the body 712, and slots 718b, 718d are provided on an opposite side of the body, resulting in a design having a preferred bending plane in the x-z plane. The diameter of the body 712 is D. The depths dl and d2 of the slots are each less than D/2, and dl + d2 < D. If desired, dl ~ d2. Similar to the slotted region 616, the transverse slots of region 716 are oriented at an inclination angle γ = 0.

In FIG. 8, a delineator 810 comprises a tubular body 812 having a first end 812a configured as a base or being adapted for affixing to a base. A slotted region 816 is provided in the tubular body. Unlike the slotted regions depicted in previous figures, the slotted region 816 comprises a continuous transverse slot 818 having a helical

configuration. The continuous slot 818 extends in a spiral fashion ("spiral" and "helical" are used here in a broad sense, and are not meant to limit the cross-sectional shape of the tubular body 812 to a circle) between points 818a and 818b. The transverse slot 818 forms a helical section 820 of the tubular body. In the depicted embodiment, the helical section 820 extends over a range of azimuthal angles of at least 360 degrees,

corresponding to at least one complete "turn", but larger or smaller ranges of azimuthal angles can also be used. The continuous nature of the slot 818, and its angular extent of at least one turn, may result in a slotted region design that can bend substantially equally in any bending plane. The inclination angle of the slot 818 can be adjusted if desired to angles other than that shown in FIG. 8, and other design parameters can also be changed.

A wide variety of delineator embodiments are contemplated herein. In some embodiments, such as that of FIG. 4, only one slotted region may be provided. In other embodiments, multiple slotted regions may be provided. In some cases, a first slotted region can be provided proximate the first or lower end of the tubular body, and a second slotted region can be provided proximate the second or upper end of the tubular body. In other cases, both the first and second slotted regions may be provided proximate the first or lower end. In still other cases, the first and second slotted regions may be provided elsewhere on the tubular body. Combinations of all of these cases are also contemplated. Any one of the slotted regions may be of the type that comprises discrete transverse slots (see e.g. FIG. 4) or a continuous transverse slot (see e.g. FIG. 8), for example.

Turning now to FIG. 9, we see there an exploded perspective view of an exemplary delineator 910 incorporating a tubular body 912 having two transversely slotted regions 916a, 916b. The body 912 has a first end 912a configured as a base or being adapted for affixing to a base. The body 912 also has a second end 912b and a central portion 912c. The slotted region 916a is shown to have four discrete transverse slots, and may have a design similar to that of slotted region 416 described previously, but it may instead have any of the alternative designs described herein. The body 912 is hollow to allow for the insertion of a first inner core 920, which may be held in place via a friction fit or by other suitable attachment mechanisms. When properly inserted, the core 920 preferably extends at least along the length of the slotted region 916a. The core 920 may be hollow or solid, and may be composed of an elastic material such as rubber. A suitable core 920 may thus function to help restore the delineator 910 to an upright position after being struck by a vehicle. Such an elastic core may also be utilized in connection with the other delineators described herein. Although in some embodiments the elastic core can extend substantially the entire length of the tubular body, in many cases the elastic core is provided over only a fraction of the length of the tubular body, e.g., less than ½ or less than 1/3 or less than ¼ thereof, for cost savings.

In addition to the slotted region 916a disposed proximate first end 912a, delineator 9 also comprises another slotted region 916b disposed proximate second end 912b. As shown, the slotted region 916b may have a substantially similar design to that of region

916a, except that it includes additional transverse slots. Alternatively, slotted region 916b may have substantially the same design as that of region 916a, or it may have a completely different design. In any case, the delineator 910 also includes a second inner core 922, which is substantially shorter than the body 912, and inserts into only the upper portion of such body. For example, the inner core 922 may have a length (height) that is less than half that of the tubular body, or less than one-fourth that of the tubular body, for example. A reflective sheet 924 is applied to an outer surface of the inner core 922, e.g. by an adhesive or other suitable means. As applied to the core, the sheet 924 has an upper edge 924a, a lower edge 924b, and an axial edge 924c. A cap or cover 926 is bonded or otherwise attached to one end of the inner core 922. After the inner core 922 is inserted into the end 912b of the body 912, portions of the sheet 924 are exposed by the slots of region 916b, which region can be considered to also constitute a window region. Other suitable window region designs can be found in copending U.S. Patent Application Serial No. 61/288581, "Delineator With Core/Shell Construction" (Attorney Docket No.

65819US002), filed on even date herewith and incorporated herein by reference, the teachings of which may be used in combination with the teachings of the present application. In the embodiment of FIG. 9, the slots of region 916b are inclined at an angle relative to a horizontal plane, and the depth of the slots is great enough to expose to at least some portion of the reflective sheet 924 for any given azimuthal angle over an entire 360 degree range. Consequently, the region 916b may be adapted to avoid exposing the upper edge 924a and the lower edge 924b of the sheet 924, but portions of the axial edge 924c will be exposed through at least some of the transverse slots (i.e., windows or apertures) of region 916b. In alternative window region designs, discussed in the above- cited U.S. Application (Attorney Docket No. 65819US002), substantially no edges of the sheet 924 may be exposed.

The tubular body 912 may be tapered or otherwise narrowed in central region 912c as shown, or at another place on the body 912. Such a narrowing may impart a distinctive appearance to the delineator, or may serve other purposes. Alternatively, such a narrowing feature may be omitted. Depending on the method of construction, the wall thickness of the tubular body 912 may be less than, greater than, or substantially equal to the wall thickness elsewhere in the body 912.

FIG. 10 is a schematic perspective view of another exemplary delineator 1010.

Delineator 1010 comprises a tubular body 1012 having a transversely slotted region 1016. The body 1012 has a first end 1012a configured as a base, or being adapted for affixing to a base as shown. The body 1012 also has a second end 1012b and a central portion 1012c. The slotted region 1016 is shown to have four discrete transverse slots, and may have a design similar to that of slotted region 916a described above, or it may have any alternative design described herein. The body 1012 may be hollow, and it may

incorporate an elastic core as described in connection with FIG. 9 to assist in restoring the delineator 1010 to an upright position after being struck by a vehicle.

Delineator 1010 also comprises reflective sheets 1022a, 1022b wrapped around an upper portion of body 1012 as shown. The sheets may have high daytime visibility, high nighttime visibility, or both. One or both of the sheets may be retroreflective. The sheets may have the same color, or be of different colors. Similar to delineator 910, delineator 1010 is tapered in a central region 1012c of the tubular body 1012.

FIGS. 1 la-c depict in schematic elevational view portions of delineators 1110, 1120, 1130 that include alternatives to the narrowing feature shown in FIGS. 9 and 10. In delineator 1110, an angled taper is used. In delineator 1130, an abrupt narrowing provides a narrow central portion of reduced diameter. In delineator 1120, a combination of an angled taper and central portion of reduced diameter is used.

FIGS. 12a-e are schematic views of some shapes that can be used for the cross- sectional shape of the tubular body of the disclosed delineators.

Some suitable cross-sectional shapes for the disclosed tubular bodies and delineators are provided in FIGS. 12a-e, but these should not be considered to be limiting. Shape 1210 is substantially circular, but elliptical shapes can also be used. Shape 1220 is somewhat flattened and elongated. Shape 1230 is substantially triangular. Shape 1240 is substantially square or rectangular. Shape 1250 is similar to shape 1210, but comprises slightly curved upper and lower "sides" as described more fully in the copending U.S. Application (Attorney Docket No. 65819US002) referenced above. For tubular bodies having cross-sectional shapes such as these, reflective sheeting can be provided on, or can be exposed via window region(s) formed in, one or more "sides" of the body. In this regard, a "side" of the tubular body may refer to the portion of the body that is visible from a particular azimuthal angle Θ (refer to FIG. 4c). Thus, for example, the delineator 910 shown in FIG. 9 has a window region (slotted region 916b) provided on all sides of the outer shell. As such, the delineator 910 may be referred to as an omnidirectional delineator, since it can provide high visibility from all azimuthal directions. For the shapes of FIGS. 12a-e, reflective sheets and/or window regions may be provided on only one side, or on multiple sides of tubular bodies represented by the shapes. For shape 1210, one or more reflective sheets and/or window regions may be provided on only one side, to provide a unidirectional delineator, or they may be provided on two sides to provide a bidirectional delineator, or on more than two sides to provide a substantially

omnidirectional delineator (which provides high visibility for any azimuthal angle). For shape 1220, one or more reflective sheets and/or window regions may be provided on only one of the long, flat sides, or on both such sides. Note that the relatively flat sides of shape 1220 may be provided with a small amount of curvature to enhance mechanical strength. For shape 1230, one or more reflective sheets and/or window regions may be provided on only one, or only two, or on all three sides of the triangle, which may result in a unidirectional, bidirectional, or tri-directional delineator, respectively. For shape 1240, one or more reflective sheets and/or window regions may be provided on only one, or only two, or only three, or all four of the substantially flat sides of the tubular body. For shape 1250, one or more reflective sheets and/or window regions may be provided on one, some, or all of the sides.

To the extent a tubular body having any of the shapes of FIGS. 12a-e is provided with one or more discrete transverse slots as part of a slotted region, such slots can be provided on any of the sides of these shapes as desired in order to promote flexing or bending of the body along any desired axial direction(s).

FIG. 13 is an exploded elevational view of a delineator 1310 having a core/shell construction. Such delineators are disclosed more fully in the copending U.S. Application (Attorney Docket No. 65819US002) referenced above. The delineator 1310 comprises an inner core 1312 and a tubular body (alternatively referred to as an outer shell) 1314.

Reflective sheets 1332, 1334 are applied to the outer surface 1312a of the inner core 1312. The shapes of the sheets 1332, 1334, their placement on the inner core 1312, and the shapes and placement of the window regions 1322, 1324 in the outer shell 1314, are preferably designed such that the sheet edges 1332a, 1334a are not exposed by the respective window regions. When the inner core is properly positioned in the outer shell, the sheet edges 1332a, 1334a preferably correspond to the dashed-line outlines that surround window regions 1322, 1324 respectively.

Preferably, the delineator is designed to be flexible so that it can bend by 90 degrees or more in response to a vehicle strike, and then rebound or recover to a vertical orientation, and one or more slotted regions as disclosed herein (not shown in FIG. 13) are provided in the outer shell 1314 proximate the bottom end 1318 to promote bending. In such flexible delineator design, the core and shell may be made of a thermoplastic polyurethane, such as such as Desmopan™ 392LS/LE material sold by Bayer, or other suitable flexible materials. The exterior height of the inner core 412 may also be made somewhat smaller than the interior height of outer shell 414, in order to provide a small gap between the top of the inner core and the bottom inside surface of the upper end 1320 of the outer shell, so as to allow for flexing.

The reflective sheets 1332, 1334 may comprise the same type of reflective sheeting, or they may comprise different sheeting. In exemplary embodiments, the sheet 1332 may comprise white (clear) retroreflective sheeting, and the sheet 1334 may comprise red-colored retroreflective sheeting. Sheetings of other colors may also be used, as desired. Although retroreflective sheeting from any vendor may be used, retroreflective sheeting sold by 3M Company is preferred. Such sheeting may include 3M™ Diamond Grade™ DG ³ Reflective Sheeting Series 4000, 3M™ Diamond Grade™ Conspicuity Markings Series 983, and/or 3M™ Diamond Grade™ Flexible Prismatic School Bus Markings Series 973, for example.

In cases where the delineator includes at least two distinct retroreflective sheets, which may correspond to at least two distinct window regions, it may be advantageous for one of the retroreflective sheets to have a first optical characteristic, and for the other retroreflective sheet to have a second optical characteristic that differs from the first optical characteristic. The optical characteristics may relate to the color of the

retroreflective sheets, and/or to the retroreflective coefficient or range of retroreflectivity of the sheets. In one case the sheet 1332 may comprise white 3M™ Diamond Grade™ DG ³ Reflective Sheeting Series 4000, and the sheet 1334 may comprise red 3M™

Diamond Grade™ Conspicuity Markings Series 983, for example. The latter sheeting (series 983) may be considered to provide enhanced retroreflectivity at long ranges, because its retroreflectivity is particularly high at very small observation angles a, which generally correspond to observation at large distances. The former sheeting (series 4000), even though it also provides very good retroreflectivity at large distances, may be considered to provide enhanced retroreflectivity at shorter ranges, because its

retroreflectivity decreases less than that of the series 983 sheeting as the observation angle a increases. Note that in addition to viewing distance, the observation angle a can also be affected by the vehicle size: in small vehicles, the distance from the vehicle headlamp to the vehicle operator's eye is generally smaller than for larger vehicles. Thus, at any given viewing distance, the operator of a small automobile, for example, will typically have a smaller observation angle a than the operator of a large truck or bus, for example.

In addition to exhibiting differences as a function of observation angle a (FIG. 3), different retroreflective products also exhibit differences as a function of entrance angle β (FIG. 2). Thus, for example, the retroreflectivity of the series 983 conspicuity sheeting mentioned above decreases less (for a given observation angle) than that of the series 4000 sheeting as the entrance angle increases, and can thus be said to have a wider entrance angularity.

The dimensions of an exemplary delineator such as that shown in FIG. 13 include: 800 mm for the height of the delineator; 440 mm for the height of the lower edge of window region 1322; 770 mm for the height of the upper edge of the window region 1322; 140 mm for the lower edge of the window region 1324; 320 mm for the upper edge of the window region 1324; and 90 mm for the maximum transverse dimension (width) of the outer shell.

The disclosed delineators and components thereof can be made using known manufacturing methods, such as injection molding, extrusion, roto-molding, sheet metal fabrication, and/or similar low cost fabrication processes.

The disclosed delineators, and components thereof, can be made of any suitable materials, including weatherable materials capable of long term use in outdoor

environments. For example, thermoplastic polyurethanes, such as such as Desmopan™ 392LS/LE material sold by Bayer, or other suitable flexible materials such as flexible rubber-like plastics or other plastics, may be used. In some cases the delineator may include one or more rigid component, made of a harder plastic or material, such as polycarbonate 15% glass filled, polycarbonate acrylonitrile butadiene styrene (ABS) glass filled, nylon glass filled, sheet metal, or other suitable rigid materials.

If a core/shell construction is used, the inner core and outer shell can be made of the same material, or different materials. The materials may both be rigid, or both be flexible, or one material may be rigid and the other may be flexible. For example, the inner core may be rigid and the outer shell may be flexible. Further, the inner core of such an embodiment may be substantially the same length as the outer shell, or it may have a length that is a fraction, e.g., ½ or less or ¼ or less, of the length of the outer shell or otherwise less than the length of the outer shell. An inner core of an elastic material such as rubber may be used with an outer shell composed of a flexible material or other suitable material.

Unless otherwise indicated, all numbers expressing quantities, measurement of properties, and so forth used in the specification and claims are to be understood as being modified by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and claims are approximations that can vary depending on the desired properties sought to be obtained by those skilled in the art utilizing the teachings of the present application. Not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, to the extent any numerical values are set forth in specific examples described herein, they are reported as precisely as reasonably possible. Any numerical value, however, may well contain errors associated with testing or measurement limitations.

Various modifications and alterations of this invention will be apparent to those skilled in the art without departing from the spirit and scope of this invention, and it should be understood that this invention is not limited to the illustrative embodiments set forth herein. For example, the reader should assume that features of one disclosed embodiment can also be applied to all other disclosed embodiments unless otherwise indicated. It should also be understood that all U.S. patents, patent application publications, and other patent and non-patent documents referred to herein are incorporated by reference, to the extent they do not contradict the foregoing disclosure.