US3924958A

US3924958A - Highway retroreflecting marker

Info

Publication number: US3924958A
Application number: US358174A
Authority: US
Inventors: William P Rowland
Original assignee: Rowland Development Corp
Current assignee: Rowland Development Corp
Priority date: 1972-12-21
Filing date: 1973-05-07
Publication date: 1975-12-09
Anticipated expiration: 1992-12-09
Also published as: USB358174I5; CA999837A

Abstract

A highway retroreflecting marker comprises a housing including a base having a relatively rigid side wall, and a resiliently depressible cap projecting upwardly from the base. The cap is substantially sealingly engaged with the side wall of the base. At least the cap of the housing is formed from a relatively wearresistant synthetic resin. The cap has a prism which is transparent to enable light rays to pass therethrough and which redirects the light rays striking the prism at an angle different from the angle at which the light rays strike the prism. A retroreflecting means is supported in the housing to enable the light rays redirected from the prism to be received thereby and to enable the light rays received thereby to be retroreflected therefrom back to the prism. The housing is adapted to be positioned adjacent a roadway so that the light rays from an approaching vehicle will strike the prism, be redirected therefrom to the retroreflecting means, then be retroreflected to the prism, and thereafter be directed from the prism back towards the approaching vehicle.

Description

O a United States Patent 1191 1111 B 3,924,958

Rowland Dec. 9, 1975 HIGHWAY RETROREFLECTING MARKER 3,216,335 11/1965 Stolarczyk 404/11 [751 Inventor: William Rowland, Millbwok 3325323 311323 335321141111: 311135.921)? 52 Lane, Southington, Conn- 06489 3,377,930 4/1968 Kone 404/11 [73] Assignee: Rowland Development Corporation,

. Kensington, C Primary ExaminerNile C. Byers, Jr.

22 Pl d: M 7 1973 I 1 ay 57 ABSTRACT [211 Appl 358l74 A highway retroreflecting marker comprises a housing [44] Published under the Trial Voluntar P t t including a base having a relatively rigid side wall, and Program on January 28, 1975 as document a resiliently depressible cap projecting upwardly from B 358,174. the base. The cap is substantially sealingly engaged Related us. Application Data, :ith the side wall of the base. At least the cap of the ousmg is formed from a relatively wear-resistant syn- [63] gg of 317,263 thetic resin. The cap has a prism which is transparent abandoned to enable light rays to pass therethrough and which redirects the light rays striking the prism at an angle difgg Cell. .hhiFmlii/lg fereht from the angle at which the hght rays strike the [58] .ld l 12 /0 prism. A retroreflecting means is supported in the 1 2 2? 6 6 housing to enable the light rays redirected from the prism to be received thereby and to enable the light rays received thereby to be retroreflected therefrom [56] References cued back to the prism. The housing is adapted to be posi- UNITED STATES PATENTS tioned adjacent a roadway so that the light rays from 1,797,498 3/1931 an approaching vehicle will strike the prism, be redi- 1,902,440 3/1933 rected therefrom to the retroreflecting means, then be 311322 retroreflected to the prism, and thereafter be directed 2:627:784 2/1953 from the prism back towards the approachmg vehlcle. 2,991,698 7/1961 Leubaz 404/16 17 Claims, 14 Drawing Figures US. Patent Dec. 9, .1975 Sheet 1 of 3 3,924,958

US. Patent Dec. 9, 1975 Sheet 2 of3 3,924,958

US. Patent Dec. 9, 1975 Sheet3of3 3,924,958

HIGHWAY RETROREFLECTING MARKER This application is a continuation-in-part of my copending patent application, Ser. No. 317,263, filed Dec. 21, 1972, and now abandoned.

BACKGROUND OF THE INVENTION It is known in the prior art to employ reflecting markers as a means to delineate the lanes including the shoulders of a highway. Particularly in Europe and in warm climates this type of highway marker is frequently used to glide motorists at night because such markers show up brighter and last longer than conventional glass filled painted highway stripes.

Each of these markers commonly consists of a strong metal housing which houses a glass or plastic prism type reflector. The marker is generally either set in a bored hole in the pavement or else is glued to the road surface by means, for example, of an "epoxy cement, in such a manner that the reflector portion of the marker projects above the road surface a sufficient distance to provide a visible reflecting surface. A disadvantage, however, of such markers is that occasionally a marker will work loose and will be hurled by a passing vehicle into the path of another vehicle.

Some use has been made of the aforementioned type of marker in snow climates. However, when so employed, the markers have exhibited a tendency to be easily dislodged by passing snow plows. Various attempts have been made heretodate to eliminate this problem as well as the problem mentioned in the preceding paragraph. In general, these effort have been directed primarily at changing the-configuration of the marker in order to provide allegedly more protection to the reflectin g surface of the marker. The markers which have been provided as a result thereof have not however, proven to be entirely satisfactory. Basically this is because the markers as modified most often are found to be more complex in structure and therefore more costly to manufacture. Also, in many instances in order to afford added protection to the reflecting surface of the marker, it has been necesssary to reduce the visible area of the reflecting surface which in turn disadvantageously affects the optical efficiency of the marker.

Another undesirable characteristic possessed almost universally by all prior art types of highway reflecting markers is the susceptibility exhibited thereby for collecting dirt, sand and road generated dust on thereflecting surface of the marker. This, of course, after a period of time will significantly reduce the optical efficiency of the marker. In an attempt to obviate this deficiency, there have been embodied into some markers some form of self-cleansin g means which is intended to be operable to periodically wipe off the reflecting surfaces. Even though many of these self-cleansing menas have in operation proven to be generally effective in accomplishing their intended function, it has nevertheless been found that to equip a marker with such a selfcleansing means normally adds significantly to the cost of manufacture of the marker. Thus, since economic considerations are generally of paramount importance in determining the extent to which such markers are employed, the net effect of increasing the cost thereof is to discourage increase usage of highway reflecting markers.

Accordingly, it is an object of the present invention to provide a novel and improved highway retroreflecting marker wherein light rays striking the reflecting surface of the marker are redirected within the marker, and then are directed back from the marker in the direction of the source of the light rays.

It is also an object of the present invention to provide such a highway retroreflecting marker wherein the redirecting surface bearing portion of the marker depresses upon being engaged by a vehicle and automatically restores itself to its orginal undepressed condition upon its disengagement therewith by the vehicle.

Another object of the present invention is to provide such a highway retroreflecting marker wherein at least the redirecting surface bearing portion thereof is formed a wear-resistant material so as to resist abrasion caused by blowing sand and grit, and suffing caused by engagement with the tires of passing vehicles or the blade of a passing snow plow.

A further object of the present invention is to provide such a highway retroreflecting marker wherein the redirecting surface bearing portion thereof is sufficiently flexible so that dirt, mud or ice which may accumulate thereon will be cracked off, i.e., dislodged therefrom when the bearing portion is caused to depress.

A still further object of the present invention is to provide such a highway retroreflecting marker which is relatively inexpensive to manufacture, is easy to employ, has a relatively long operating life, while yet being capable of efficiently directing light rays which strike the marker back in the direction of the source thereof.

Yet another object of the present invention is to provide an effective method of delineating particular portions of a road surface by causing light rays, produced by a passing vehicles lights, to strike markers designating particular road surface portions be reflected within the markers, and then be directed from the markers back towards the vehicle.

SUMMARY OF THE INVENTION It has now been found that the foregoing and related objects can be readily attained by means of a highway retroreflecting marker comprising a housing which includes a substantially rigid base, and a resiliently depressible cap projecting upwardly from the base. The cap is preferably formed of a relatively wear-resistant synthetic resin and has a prism which is transparent to enable light rays to pass therethrough. The prism also functions to redirect the light rays within the housing at an angle different from the angle at which the light rays strike the prism. A retroreflecting means is supported in the housing in such a manner as to enable the retroreflecting means to receive light rays redirected from the prism and to enable these light rays to be retroreflected back to the prism. To employ the highway retroreflecting marker, the latter is positioned such that the base thereof is located below road level and the cap thereof is located above road level whereby light rays striking the prism are redirected within the housing, and then redirected back to the prism and from the prism directed back in the direction of the striking light rays.

In accordance with the preferred embodiment of the invention, the housing of the highway retroreflecting marker is made in two parts, and means are provided for joining the cap in sealingly engaging relation with the base such that a substantially air-tight seal is formed therebetween, and whereby under the influence of an external force the cap is free to depress into the base compressing the air therein and upon removal of the external force the cap will be returned by the air to its former undepressed condition. The cap of the housing is formed in a plurality of four or five steps with each step including a prism. By virtue of the step construction, each prism is afforded the protection of a natural protective shoulder. A retroreflecting means is mounted on the bottom wall of the base to receive light rays which are redirected within the housing by the prism and to retroreflect the light rays back to the prism. For the the most effective operation thereof, the retroreflecting means is positioned so that the light rays will incident thereon at an angle within of normal. The base is provided with a small vent means which enables water vapor to be vented therefrom, while at the same time permitting the housing to remain sufficiently air tight that the cap upon being depressed is still capable of restoring itself to its undepressed condition.

Certain objects of the invention may be attained in accordance with the method wherein portions of a highway are delineated by a retroreflecting marker having a reflective surface. In accord with this method, a marker is placed in a hole below road level so that the redirecting means of the marker projects above road level. The marker is positioned so that the redirecting means thereof will be struck by the horizontal light rays produced by an approaching vehicles lights. Upon striking the redirecting means the horizontal light rays are redirected 90 in an approximate downward beam onto a retroreflecting means. The beam is then retroreflected upwardly from the retroreflecting means back to the redirecting means. From the redirecting means the beam is directed back horizontally towards the approaching vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a top plan view of a highway retroreflecting marker constructed in accordance with the present invention;

FIG. 2 is a side elevational view of the highway retroreflecting marker of FIG. 1 in accordance with the present invention;

FIG. 3 is a side elevational view similar to FIG. 2, of the highway retroreflecting marker of FIG. 1, but with parts broken away for purposes of clarity of illustration;

FIG. 4 is a cross-sectional view on an enlarged scale 4 a road surface and with parts broken away for purposes of clarity of illustration;

FIG. 11 is a side elevational view of a portion of a prism of a highway retroreflecting marker in accordance with the present invention illustrating the angle of reflection of light rays striking the prism;

FIG. 12 is a side elevational view of a portion of a distorted prism illustrating the angle of reflection of light rays striking a distorted prism;

FIG. 13 is a side elevational view of yet another embodiment of highwaysretroreflecting marker in accordance with the present invention; and

FIG. 14 is a side elevational view of yet still another embodiment of highway retroreflecting marker in accordance with the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS Referring to FIGS. 1-4 of the drawings, there is illustrated therein a highway retroreflecting marker, generally designated by reference numeral 10. The marker 10 includes a cap 12, a base 14, and means 16 for seof a portion of the prism of the highway retroreflecting marker of FIG. 1 in accordance with the present invention;

FIG. 5 is a cross-sectional view of another embodiment of highway retroreflecting marker in accordance with the present invention;

FIG. 6 is a side elevational view with parts broken away for purposes of clarity of illustration of still another embodiment of highway retroreflecting marker in accordance with the present invention;

FIG. 7 is a cross-sectional view of a further embodiment of highway retroreflecting marker in accordance with the present invention;

FIG. 8 is a cross-sectional view of a still further embodiment of highway retroreflecting marker in accordance with the present invention;

FIG. 9 is a top plan view of an alternate construction of a base employable with a highway retroreflecting marker constructed in accordance with the present invention;

FIG. 10 is a side elevational view of the base of FIG. 9 illustrated positioned in a hole provided therefor in a curing the cap 12 to the base 14. The cap 12 is formed from a relatively wear-resistant synthetic resin. In this connection it has been found that a synthetic resin suitable for this purpose is aliphatic isocyanate type urethane Dupont No. 2699, manufactured by Dupont Company of Delaware, which has been cured with polyol type curing agent 80, part I, 4 butanediol and 20 part trimethylol propane modified to be as resistant to weathering and ultraviolet light as possible.

As shown in FIGS. l-4 the cap 12 is preferably molded so as reference have a stepped construction. More particularly, the cap 12 is made so as to include a plurality of steps 18. Although the cap 12 is depicted in the drawings as including four steps 18, it is to be understood that the cap 12 could also include a greater or a lesser number of such steps without departing from the essence of the invention. The cap 12 further includes a plurality of prism elements or portions 20. The latter are suitably mounted on the inner surface of the cap 12 adjacent to the three uppermost steps 18 as viewed with refereence to FIGS. 3 and 4 of the drawings. For this purpose, the cap 12 is molded so as to be provided with three triangularly shaped portions 22. Each of the portions 22 includes a surface 22a which is inclined at an angle of approximately 45 to the planes of the steps 18. The surfaces 22a constitute the light reflecting surfaces and accordingly must be smooth and shiny to function properly. At least the three triangularly shaped portions 22 of the cap 12 are made so as to be transparent whereby to enable light rays, in a manner to be more fully described subsequently, to pass therethrough and strike the light reflecting surfaces 22a. Finally, the cap 12 also is preferably provided along its open end with a rim 24 capable of co-operating with securing means 16 in a manner which will be described more fully hereinafter.

Turning now to a consideration of the base 14, the latter constitutes a canister having a substantially rigid cylindrically shaped side wall 26 closed at one end by a bottom wall 28. Although the base 14 is preferably made of metal, it is to be understood that other materi als, including synthetic resins, or tempered glass, capable of providing the desired degreee of rigidity to the side wall 26 could also be employed without departing from-the essencce of the invention. A retroreflecting means 30 comprising one or more reflecting elements is suitably mounted on the inner surface of bottom wall 28. Retroreflecting means 30 is retained on bottom wall 28 by any suitable securing means 32. The securing means 32 may take the form of an adhesive, retaining members and fasteners for fastening the members to the bottom wall 28, etc. If the base 14 is formed from resin, the retrorefiecting means 30 may be secured to the bottom wall 28 by being molded thereto, or by being embedded therein. The retrorefiecting means 30 is located on the bottom wall 28 so as to receive light rays redirected, in a manner yet to be described, from the light reflecting surfaces 22a. In accordance with the preferred embodiment of highway retrorefiecting marker 10, the base 14 is provided with a small vent means 34 suitable provided in the side wall 26. The vent means 34 functions as a means of enabling water vapor to pass from the interior of the base 14 to the exterior of the marker without permitting water to flow into the base 14.

Considering next the method of assembling the marker 10, the cap 12, which as previously described is formed from the resilient material, is slid over the open end of the base 14, the latter being provided with a substantially rigid side wall 26. For this purpose, the internal diameter of the open end of cap 12 dimensionally corresponds to the external diameter of the base 14. With the cap 12 positioned on the side wall 26 in frictional engagement therewith, the means 16, which as sown in FIGS. 2 and 3 of the drawings preferably comprises a conventional snap ring, is slid over the cap 12 and snapped into place against the rim 24 whereby to hold the cap 12 securely positioned on the base 14. The securing force imparted by the snap ring 16 is selected to be such that the joint between cap 12 and base 14 is substantially air-tight.

With particular attention directed to FIG. 2, the method of employing the marker 10 will now be set forth. The marker 10 is first assembled as described in the preceding paragraph. A hole 36 is bored in the road surface 38 to receive the marker 10. Accordingly, the circumference of the hole 36 is made such that it corresponds to the circumference of the rim 24 of cap 12. Preferably the hole 36 is bored clear through the hard surface, bituminous concrete, or plain concrete of the road surface 38 so that water will be free to drain to the rock drainage bed under the road. The depth of the hole 36 therefore exceeds the depth of the base 14. Thus, the hole 36 is commonly filled with sand to a depth whereat when the marker 10 is positioned in the hole 36, the bottom step 18 as viewed in FIG. 2 is substantially at road level. The marker 10 is then placed in the hole 36, and is oriented therein such that the prism portions 20 of the marker 10 are facing in the direction of approaching vehicles.

With the marker 10 so positioned in hole 36, when a vehicle approaches with its lights ON, the horizontal light rays produced by the vehicles lights strike as schematically represented in FIG. 3 by the dotted line 40 the prism portions 20. Only one dotted line 40 has been depicted in FIG. 3 in the interest of clarity of illustration, but it is to be understood that other light rays would be simultaneously striking the other prism portions 20. The prism portions 20 which function similar in nature to a 90, 4545 binocular prism, reflect the horizontal light rays, i.e., beam of light 90 to an approximate downward beam whih is schematically depicted in FIG. 3 by dotted line 42. Supported in a substantially horizontal attitude on the bottom wall 28 of base 14 is the retrorefiecting means 30 which receives the aforedescribed downward beam of light. Upon striking the retrorefiecting means 30, which may be comprised of a plurality of small glass bead type reflectors or may be comprised of a plurality of small cube corner reflectors, the beam of light made up a plurality of substantially parallel incoming light rays is retroreflected back in the direction of dotted line 42 to the prism portions 20. Upon once again striking the prism portions 20, the beam of light is redirected and is directed horizontally back towards the approaching vehicle. The reflecting elements which comprise the retroreflecting means 30 preferably are made as small as practicable so that the light rays being retroreflected therefrom are as close to the incoming light rays as possible in addition to being parallel to the incoming light rays. Otherwise, some of the light rays being retroreflected from the retrorefiecting means 30 to the prism portions 20 will hit the steps 18 of the cap 12 rather than the prism portions 20 thereof and will not be directed towards oncoming traffic. For convenience of manufacture, the prism portions 20, if so desired, may be supported in cap 12 at some angle other than that depicted in FIGS. 1-4 of the drawings. That is, the prism portions 20 may be so mounted such that horizontal light rays which strike the prism portions 20 will not be redirected vertically but rather at some lesser or greater angle thereto. In which case, the retrorefiecting means 30 should be supported in the base 14 such that the beam of light being redirected by the prism portion 20 will incident, for purposes of most effective usage of the retrorefiecting means 30, upon the latter at an angle of no more than 10 from normal. However, it has been found that the marker 10 is operable for angles of up to 30. For light to enter a transparent body such as glass or plastic, it can do so most efficiently when the light enters at a path normal to the surface. As the angle of incidence increases, more and more light is reflected off the surface and what light does enter the body is refracted at an angle. Accordingly, the markers constructed in accordance with the present invention are all preferably provided with a stepped vertical surface to receive the light from a motor vehicles headlights. As shown in FIG. 6 however, if so desired, a marker having a non-stepped vertical surface may be provided, as will be described more fully hereinafter. The marker of FIG. 6 although still operable, will reflect light less efficiently than the marker wherein a stepped vertical surface is provided.

Referring again to FIGS. 1-4 of the drawings, the cap 12 of marker 10 as described previously is sealingly engaged to the base 14 such that an air-tight seal is formed therebetween. Thus, when the resilient cap 12 is hit by a tire of a passing vehicle or the blade of a passing snow plow, the cap 12 is free to depress into the base 14 compressing the air therein. When the tire or snow plow blade which hit the cap 12 passes out of engagement therewith, the air in the base 14 which has been compressed returns the cap 12 to its former undepressed condition without any damage having been incurred by the cap 12. The type of polyurethane material from which the cap 12 is preferably formed is specifically selected to be resistant to abrasion from blowing sand and grit, and scuffing from ties and scraping of snow plow blades. ln addition, this material resists hydrolysis at elevated temperatures. By having the surface of the cap 12 made in several steps 18, a natural protective shoulder is provided to keep tires and other objects from contacting the reflecting surfaces of the cap 12. The practical effect of the step construction in this connection is that it reduces the overall angle of attack of vehicle tires and snow plow blades striking the cap 12. In addition, the stepped construction reduces the amount of material needed to form the cap 12 while it simultaneously inherently protects the optically smooth prism surfaces thereof. Another characteristic of the cap 12 is that it is substantially flexible so that any dirt, mud or ice which accumulates thereon will be cracked off the surface of the cap 12 when the latter depresses.

Because the marker 10 when positioned in the hole 36 is continuously exposed to all types of weather conditions which may vary greatly from day to day particularly with regard to temperatures, it is preferred to provide the previously described small vent means 34 in the side wall 26 of base 14. The vent means 34 is intended to permit water vapor to pass from the interior of the base 14 while at the same time preventing a reverse flow of water into the base 14. To accomplish this function, the vent means 34 preferably includes a diaphragm membrane of the type which is well know to those skilled in the art and which has commonly been utilized heretofore for this purpose in other applications. In the absence of such a vent means 34 temperature differentials existing between the inside and outside of the marker 10 could conceivably lead to the establishment of the vacuum'within the base 14. Such a vacuum could cause the cap 12 to depress into the base 14 and remain so positioned therein. The vent means 34 functions to minimize the possibility of such a condition occurring. Of course, the vent means 34 must only be made as large as necessary to enable water vapor to escape from the inside of the base 14 while at the same time not being so large as to rupture the air-tightness of the marker 10 whereby the air in the base 14 would not be compressed when the cap 12 is depressed and thus the air would be incapable of functioning to return the cap 12 to its undepressed condition.

For optical purposes, the cap 12, of course, need not be provided with a step construction. The steps 18 are preferably provided primarily for mechanical and economical reasons as set forth with more particularity in the preceding paragraphs. As such, other forms of highway retroreflecting markers embodying configurations which differ from that of the marker 10 depicted in FIGS. 1-4 of the drawings are also contemplated in accordance with the present invention. In this connection, reference is made to FIG. of the drawings wherein another embodiment of highway retroreflecting marker, designated therein by reference numeral 44, constructed in accordance with the present invention is shown. The highway retroreflecting marker 44 insofar as concerns the structure thereof is very similar to the aforedescribed marker 10. That is, the marker 44 includes a cap 46, a base 48, and means 50 for securing the cap 46 to the base 48. As best seen with reference to FIGS. 5 and 3 of the drawings, the primary difference between the marker 44 and the marker resides in the configuration of their respective caps, i.e., cap 46 and cap 12, respectively. More specifically, whereas the cap 12 of marker 10 is provided with a stepped construction, the cap 46 of marker 44 is provided with a top hat-like configuration. The latter is circular in shape, and therefore is capable of reflecting light from any direction. As such, this construction makes the 8 marker 44 ideally suited for use in airports, parking lots, etc.

Prism portions 52 are mounted within the cap 46 in a manner similar to that described previously in connection with the description of the retention of prism por tions 20 in cap 12. That is, the prism portions 52 are lo cated in the cap 46 such as to lie at an angle to the plane of the top surface 46a of cap 46. Furthermore, as in the case of cap 12, the cap 46 is formed so as to be transparent at least in the vicinity of the prism portions 52 in order to enable light rays to pass through the cap 46 and strike the prism portions 52. The cap 46 is secured to the base 48 in the same manner as that described above in connection with the mounting of cap 12 on base 14. Similarly, the mode of operation of marker 44 is the same as marker 10. That is, the marker 44 is adapted to be positioned in a hole (not shown) suitably provided for this purpose so that the prism portions 52 thereof are oriented in the direction of ap proaching traffic and are visible thereto. With the marker 44 so positioned, light .rays produced by the lights of an approaching vehicle strike the prism portions 52 and are redirected downwardly where they are received by the retroreflecting means 54 mounted on the bottom wall 48a of the base 48. These light rays are then retroreflected from the retroreflecting means 54 to the prism portions 52 and directed therefrom back into the path of oncoming traffic. The reflection of the light rays from the marker 44 thus serves to delineate that portion of the highway surface where the marker 44 is located. As in the case of marker 10, should the marker 44 be struck by the tire of a passing vehicle, etc., the cap 46 will depress into the base 48, compressing the air therein. Once the tire or other object passes from engagement with the cap 46, the air in the base 48 will cause the cap 46 to return to its former undepressed state.

Referring next to FIG. 6 of the drawings, there is illustrated therein another embodiment of a highway retroreflecting marker, generally designated by reference numerals 56, constructed in accordance with the pres ent invention, and which like the marker 44 is circular in shape. The marker 56, although structurally it also embodies a cap 58 and a base 60, differs somewhat in construction from either the marker 44 or the marker 10. The basic difference therebetween resides in the fact that in the marker 56, cap 53 is joined to the base 60 in a manner different from that which has been heretofore set forth in connection with the description of

markers

44 and 10. More specifically, in the marker 56 the open end of cap 58 is inserted into the open end of the base 60 rather than having the base inserted into the open end of the cap as in the case of both marker 44 and marker 10. Preferably, sufficient resiliency exists between the side wall 58a of cap 53 and the side wall 60a of base 60 so that the cap 58 can be inserted into the base 60 with a snap fit which is sufficiently tight to ensure a substantially air-tight seal therebe tween. However, if so desired, a suitable adhesive may also, of coursse, be utilized for purposes of affixing the cap 58 more securely to the base 60. In addition to the aforedescribed difference, the cap 58 also differs in configuration from either the marker 44 or the marker 10. In this connection, the cap 58 embodies a generally pyramidically shaped configuration, and has mounted thereon prism portions 62, suitably located such that lightrays striking the prism portions 62, as illustrated schematically by dotted line 64 in FIG. 6, are redi- 9 rected therefrom downwardly as shown by dotted line 66 to retroreflecting mens (not shown) suitably retained on the bottom wall of base 60 in a manner similar to that previously described above in connection with the retroreflecting means 54 and 30 of

markers

44 and 10, respectively. As noted previously, the marker 56 reflects light rays less efficiently than do any of the other markers described previously. This is because the configuration of the cap 58 is such that the light rays strike the cap 58 at an angle other than normal. Accordingly, some of the light rays are reflected off of the surface of the cap 58 while the light rays which enter the body of the latter are refracted at an angle. The mode of operation of the marker 56 is the same as that described hereinabove with regard to the

markers

44 and 10, and as such it is not deemed to be necessary to include herein a further description of the mode of operation of the marker 56, except to note that the cap 58 is also capable of being depressed into the base 60 and of being returned to its undepressed state by the air which is compressed in the base 60 when the cap 58 is depressed therein.

In FIG. 7 of the drawings, there is shown another embodiment of highway retroreflecting marker, identified therein generally by reference numeral 68, which is constructed in accordance with the present invention. The marker 68 structurally is substantially identical to the marker 56 except insofar as concerns the configuration of the

respective caps

70 and 58 of the

makrers

68 and 56. The manner in which the cap and base of

markers

56 and 68 are joined is more clearly understood with reference to FIG. 7 of the drawings, and the illustration therein of the joint between the cap 70 and base 72 of the marker 68. The cap 70 of marker 68 is formed such as to include a plurality of layer-

like portions

70a, 70b and 700 which have decreasing surface area. Each of these layer-

like portions

70a, 70b and 700 is suitably provided with prism portions 74. The prism portions 74 function in the same manner as that described previously for the respective prism portions of each of the other embodiments of markers. Thus, horizontal light rays striking the prism portions 74 are redirected downwardly onto the retroreflecting means 76 positioned on the bottom wall of base 70 and are retroreflected therefrom to the prism portions 74 which in turn direct the light rays received thereby back into the path of approaching vehicles. Here also, the cap 70 of marker 68 is preferably made from the same type of synthetic resins as the cap 12 of marker 10 such that the cap 70 is capable, when struck, of freely depressing into the base 72 and of being returned to its undepressed condition under the influence of the air compressed in the base 72 when the striking object passes from engagement with the cap 70.

FIG. 8 depicts a still further embodiment of highway retroreflecting marker constructed in accordance with the present invention, and which has been designated therein generally by reference numeral 78. The marker 78 includes a cap 80 and a base 82. The cap 80, which is formed preferably from the same type of transparent synthetic resin as the cap 12 of marker 10 has a generally dome-like configuration. The cap 80 along its interior is provided with a prism, i.e., reflecting surface 84. the marker 78 differs in two major respects from any of the other embodiments of markers which have been previously described. The first of these differences resides in the fact that in the marker 78 the retroreflecting means 86 are mounted in the cap 80 rather than on 10 the bottom wall of the base 82 as in the case of the other markers which have been previously described. Secondly, the marker 78 is provided with a spring 88 which imparts an upper force against the cap 80, i.e., biasing the cap 80 to its undepressed condition. Referring again to FIG. 8 of the drawings, it can be seen that the spring 88 is positioned within the base 82 so as to have one end thereof abutting against the seat 822 provided therefor on the bottom wall of base 82. 'With the spring 88 so positioned therein, the marker 78 is assembled by inserting the open end of base 82 into the open end of the cap 80. The diameter of the cap 80 and base 82 are made such that the fit between the cap 80 and base 82 is sufficiently tight that the side wall 80a of cap 80 will securely encircle the side wall 82b of base 82 and will remain insealingly engagement therewith notwithstanding the upward force being applied to the cap 80 by the spring 88, which in the assembled condition of the marker 78, has its other end in abutting engagement with a seat 80b suitably provided for this purpose in the cap 80. Because of the differences in construction, the manner of operation of the marker 78 differs in some respects from that described previously for the other embodiments of markers illustrated in FIGS. 17 of the drawings. More specifically the manner of operation of the marker 78 in such that with the latter suitably-positioned in a hole (not shown) with the cap 80 thereof projecting above road level, horizontal light rays coming from the light of an approaching vehicle will strike the prism surface 84, as depicted schematically by the dotted lines 90 in FIG. 8. As discussed above in connection with the marker 56 of FIG. 6, to the extent that the light rays striking the cap 80 do so at an angle other than 90, some of the light rays will be reflected from the surface of the cap 80 while those which do pass into the body of the cap 80 will be refracted at an angle. The latter light rays are then redirected upwardly from the prism surface 84, as schematically represented in FIG. 8 by the dotted lines 92, to the retroreflecting means 86 mounted in the top portion of the cap 80. The light rays striking the retroreflecting means 86 are then retroreflected back from the retroreflecting means 86 to the prism surface 84 and are thereafter directed back from the prism surface 84 into the .path of approaching vehicles. The reflection of these light rays back from the prism surface 84 functions to delineate that portion of the highway surface in which the marker 78 is positioned. In the event that cap 80 is struck by the tire of a passing vehicle, etc., the cap 80 will depress into the base 82 against the bias of spring 88. Thereafter, when the striking object passes from engagment with the cap 80, the spring 88 will return the cap 80 to its upper, i.e., normally undepressed position. Thus, because of the use of the spring 88, it is not esential that a substantially air-tight seal be provided at the joint between cap 80 and base 82 since the compression of the air in the base 82 when the cap 80 depresses therein is not being relied upon for purposes of returning the cap 80 to its undepressed condition. Further, there is less need to provide suitable vent means (not shown) in the side wall of the base 82. On the other hand, if so desired, the spring 88 could be eliminated from the marker 78 and the compression of air in the base 82 employed to return the cap 80 to its undepressed condition in the same manner as that set forth hereinabove in connection with the description of marker 10. Finally, as shown in FIG. 8, fillets 94 may be formed at suitable locations on the external surface of 1 1 the cap 80 as a form of guide means to be engaged by the blade of a passing snow plow should the latter strike the cap 80.

Turning next to a consideration of FIGS. 9 and 10 of the drawings, there is depicted therein a base 96, embodying an alternate construction, which is capa ble of being employed as one of the components of a highway retroreflecting marker constructed in accordance with the present invention. The base 96 includes a canister portion 98 and a stand 100 provided therefor. The portion 98 may be made from any suitable material such as metal, a synthetic resin, or even of glass which has been tempered so that in the event of breakage it will shatter to harmless small pieces. The portion 98 is substantially cylindrical in shape and is provided with a bulge 98a formed along its rim. The bulge 98a is intended to coact with the side wall portion of a cap to secure the latter to the base 96 to form a highway retroreflecting marker. Although not shown it is to be understood that suitable retroreflecting means capa ble of receiving light rays redirected thereto from the prism portion of a cap would be mounted on the interior of the bottom surface of the portion 98. The canister portion 98 is mounted in a stand 100 formed of a suitable material such as, for example, aluminum. The stand 100 as depicted in FIG. 9 is provided with four outwardly extending flexible arms 102. Any suitable means may be utilized to mount the canister portion 98 on the stand 100 such as, for example,,by forming the portion 98 and the stand 100 as an integral assembly, by providing the portion 98 with strap-like portions through which the arms 102 may be inserted, by providing the portion 98 with a plurality of suitably located spaced indentations into which projections formed for this purpose on the stant 100 may be snapped, etc. However, irrespective of the manner in which the stand 100 is affixed to the canister portion 98, the important thing is that the arms 102 of stand 100 remain free such that when the base 96 is inserted into a hole 104 bored into a suitable road surface, the arms 102 are capable of flexing inwardly as they engage the side walls of the hole 104. The arms 102 thus serve as a means of firmly retaining the base 96 suitably positioned in the hole 104. In addition, the stand 100 is also preferably provided with a staking member 106 which projects outwardly from the bottom of stand 100 and which is adapted to be driven into the bottom of hole 104 thereby to more securely retain the base 96 therein.

FIG. 11 illustrates schematically the path taken by horizontal light rays as they pass through a cap 108 and strike a reflecting surface 110. As viewed therein the horizontal light rays, represented schematically by the dotted lines 112, strike the external surface 1082 of the prism, i.e., cap 108 and are all deflected uniformly towards the reflecting surface 110. Striking the surface 110, the light rays are redirected approximately 90 in a downwardly direction, the latter being depicted schematically through the use of the dotted lines 114. As the vetical light rays pass through the bottom surface 108b, they are again uniformly deflected slightly. In the above discussion, it is, of course, assumed that the cap, i.e., prism 108 is made of a transparent material.

FIG. 12 illustrates schematically the path followed by horizontal light rays when they strike a cap 116 acts as a distorted prism. As depicted therein, the horizontal light ray, schematically represented by dotted line 118 strikes the external surface 116a and is deflected in a slightly downward direction against the reflecting sur- 12 face 120. Striking the latter surface 120, the light ray represented by dotted line 118 is redirected approximately 90 in a vertical direction, as schematically depicted by means of dotted line 122. On the other hand, the horizontal light ray represented by dotted line 124 in FIG. 12, upon striking the external surface 116a is deflected thereby slightly upwardly against the relfecting surface 116a is deflected thereby slightly upwardly against the reflecting surface 120. Upon striking the surface 120, this substantially horizontal light ray is also redirected approximately 90 in a vertical direction as schematically shown by means of dotted line 126. Thus, with reference to FIGS. 11 and 12 of the drawings, it can be seen that the optical efficiency of a highway retroreflecting marker constructed in accordance with the present invention and embodying either the cap 108 or th cap 116 does not depend on the accuracy of the external surface of the respective cap, i.e., the accuracy of the prism shape. For as shown with reference to FIG. 12, when the light rays pass through the distorted external surface 116a of cap 116 they will return equally and correctly distorted, and as shown in FIG. 11, when the light rays pass through the undistorted external surface 108a of cap 108 they will return equally and correctly undistorted.

Turning now to FIG. 13 of the drawings, there is depicted therein a cap 128, which is capable of being supported on a base such as the base 96 of FIGS. 9 and 10 of the drawings whereby to provide a highway retroreflecting marker in accordance with the present invention. For this purpose, the cap 128 is provided with a vertically extending depending flange 130, which is dimensioned so that a base (not shown) may be inserted therein with a snap fit whereby to secure the cap 128 and the base (not shown) together. As illustrated in FIG. 13, one face 132 of the cap 128 is configured so as to be substantially straight, i.e., is not provided with a step-like configuration. A plurality of prism portion 134 are provided adjacent the inner surface of the face 132. The nature and function of the prism portions 134 are substantially the same as that of the prism portions 22 of cap 12 which have been described previously hereinabove. More particularly, with the cap 128 mounted on a suitable base and this assembled unit positioned adjacent a roadway so that the light rays of an oncoming vehicle will strike the face 132 of cap 128, the light rays as schematically represented by dotted line 136 in FIG. 13 pass through the face 132 and are deflected slightly as they pass therethrough. The light rays strike the prism portions 134 and are redirected in a generally downwardly direction as indicated by means of the dotted line 138, to a retroreflecting means (not shown) suitably mounted within the base (not shown) on which the cap 128 is supported. From the rtroreflecting means the light rays are retroreflected back to the prism portions 134 from where the light rays are directed back towards the oncoming vehicle from whence the light rays originated.

With the face 132 of the cap 128 configured as shown in FIG. 13, it has been found that when the face 132 is engaged by the tire of a passing vehicle, a rubbing action takes place between the tire and the face 132. The effect of this rubbing action is to clean from the face 132 any dry dust and/or oily film which may have accumulated thereon. This self-cleaning feature of the cap 128 is a desirable characteristic thereof.

As'was mentioned previously hereinabove, the light rays which strike the face of a highway retroreflecting marker constructed in accordance with the present invention may be redirected within the housing at some angle other than 90, in which case the retroreflecting means supported within the marker 10 is suitably located whereby to be positioned so that the light rays which are being redirected will incident upon the retroreflecting means. This is most clearly understood with reference to the illustration of the highway retroreflecting marker 140 depicted in FIG. 14 of the drawings. As shown therein, the marker 140 includes a cap 142 and a base 144. Both the cap 142 and the base 144 have a substantially circular shape. The cap 142 is provided with a vertically extending depending flange 146, the diameter of which is such that the base 144 is capable of being inserted therein with a snap fit whereby to securely mount the cap 142 on the base 144. Although not shown, it is to be understood that some other form of securing means could be utilized, if so desired, for purposes of mounting the cap 142 on the base 144. The cap 142 is provided with a face 148 which is substantially straight, i.e., does not have one or more steps formed therein. A plurality of prism portions'l50 are provided adjacent the inner surface of the face 148. As indicated by the dotted

lines

152, 154 and 156,the mode of operation of the marker 140 is such that when light rays from an oncoming vehicle strike the face 148, they pass therethrough the strike the prism portions 150. This causes the light rays to be refracted so that they are redirected within the marker 140 at an angle of approximately 45 from the angle at which the light rays entered the marker 140. However. it is to be understood that these light rays could also be refracted at some angle other than 45.

A retroreflecting means 158 is depicted in FIG. 14 of the drawings, supported within the base 144 in a position wherein the redirected light rays may incident thereupon. The retroreflecting means 158, which may have any of the constructions which have been set forth hereinabove in connection with the description of the other retroreflecting means, is operable to reflect the light rays which strike it back towards the prism portions 150 and the inner surface of the face 148 from whence the light rays are redirected back towards the oncoming vehicle. It should be noted that the light rays which strike the retroreflecting means 158 are redirected thereagainst as a result of being refracted. During the course of the description of at least some of the markers set forth previously, reference has been made to the light rays being reflected to the retroreflectng means. However, the significant fact is not whether the light rays are redirected by being reflected from the prism portions or whether they are redirected by being refracted, but rather that the light rays be redirected substantially perpendicular to the plane of the retroreflecting means. In this regard, the marker significantly is provided with retroreflecting means suitably supported therein whereby the light rays after being redirected either by being reflected or refracted will incident upon the retroreflecting means at an angle of not more than 10 from normal, and then will be retroreflected back towards the prism portions from whence they are directed back in the direction of the oncoming vehicle.

Although not shown in the interest of maintaining clarity of illustration, the retroreflecting means 158 may be supported on a base of charcoal. Such a charcoal base is effective to absorb at least some of the water vapor which may tend to accumulate within the marker 140. Water vapor will tend to accumulate within the marker when the latter is employed in applications wherein the inside and the outside of the marker 140 are subjected to different temperatures. As was mentioned earlier, another means of eliminting this water vapor is to provide the marker 140 with suitable vent means (not shown) which is operable to permit water vapor to pass therethrough to the outside of the marker 140 while at the same time preventing water from entering the interior of the marker 140. Where provided, the dimensions of such vent means are so small that it has been found that when the cap of the marker is depressed by virtue of the wheel of a vehicle passing thereof, air is not forced out of the marker through the vent means but rather the air is compressed within the marker. This results primarily from the fact that the wheel is in contact with the cap for a relatively brief period, i.e., the wheel passes very rapidly over the cap.

Although a plurality of highway retroreflecting markers constructed in accordance with the present invention have been described hereinabove and illustrated in the drawings, it is to be understood that many other modifications may be made therein without departing from the essence of the invention. Thus, for example, the cap could be formed from a variety of different synthetic resins as long as the cap retained its desired degree of resiliency and resistance against wear. Similarly, the base of the marker may be formed from metal, a synthetic resin, or even tempered glass. In addition, the cap may be configured in a variety of other differing shapes as long as there as prism, i.e., redirecting surfaces supported therein which would be visible, when the marker is positioned in a suitable hole in a road surface, to the lights of approaching vehicles. The cap and base may be joined by any suitable means such as through the use of adhesives, a metal wire, a snap ring, etc., as long as the particular securing means employed is capable of providing the desired degree of tightness between the cap and the base. As described above, the retroreflecting means comprises a plurality of small glass bead type reflectors. The latter may be of the exposed glass bead type, the encapsulated glass bead type, or the embedded glass bead type. However, if so desired, the retroreflecting means could also comprise a plurality of small reflecting corner cube prism elements. Although preferably, a highway retroreflecting marker constructed in accordance with the present invention is provided with a suitable small vent means, it is to be understood that for some applications in which the highway retroreflecting marker is to be employed such a vent means may be unnecessary.

To utilize the highway retroreflectin g marker for purposes of delineating a portion of a highway surface, the marker is positioned in a hole in that portion of the highway surface, so that the redirecting means is properly oriented in the direction of oncoming traffic. When a vehicle approaches with its lights ON, light rays therefrom will strike the redirecting means of the marker and be redirected to a retroreflecting means mounted within the marker. The light rays striking the retroreflecting means are retroreflected back to the redirecting means. The light rays upon striking the redirecting means are directed back substantially horizontal into the path of the oncoming traffic. The reflection of these light rays back from the redirecting means of the marker, after having been redirected and retroreflected within the marker, operates to delineate that portion of the highway surface in which the marker has been emplaced.

Thus, it can be seen that the present invention provides a novel and improved highway retroreflecting marker wherein light rays striking the reflecting surface of the marker are redirected and retroreflected within the marker, and then are directed back from the marker in the direction of the source of the light rays. In accord with the present invention redirecting surface bearing portion of the highway retroreflecting marker depresses upon being engaged by an object and automatically retores itself to its former undepressed condition upon the disengagement therefrom of the object. The highway retroreflecting marker of the present invention has at least the directing surface bearing portion thereof formed from a wear resistant resilient material so as to resist abrasion caused by blowing sand and grit, and scuffing caused by engagement with the tires of passing vehicles and scraping caused by engagement with the blade of a passing snow plow. Further, the resiliency of the surface bearing portion is such that dirt, mud or ice which may accumulate thereon will be dislodged therefrom when the bearing portion is caused to depress. Moreover, there has been provided in accordance with the present invention a highway retroreflecting marker which is relatively inexpensive to manufacture, which is easy to employ, which has a relatively long operating life, yet still is capable of efficiently reflecting light rays, which strike the marker, back in the direction of the source thereof. Finally, in accord with the present invention there has been provided an effective method of delineating particular portions of a road surface by causing light rays, produced by a passinig vehicles lights, to strike markers designating the particular road surface portions, be redirected and retroreflected within the markers, and then be directed form the markers towards the approaching vehicles.

Having thus described the invention, I claim:

1. A highway retroreflecting marker comprising; a housing having a base and a resiliently depressible cap projecting upwardly therefrom, at least said cap being formed from a relatively wear-resistant synthetic resin, said cap being substantially sealingly engaged with said base, and retroreflecting means supported in said housing, said cap having a redirecting means which is transparent to enable light rays to pass therethrough and which redirects the light rays striking said redirecting means to an angle of less than 30 to the perpendicular to the plane of said retroreflecting means, said housing being adapted for positioning of said base thereof and said cap thereof relative to a road surface so that light rays striking said redirecting means are redirected within said housing to said retroreflecting means, then are retroreflected from said retroreflecting means to said redirecting means, and thereafter are directed back from said redirecting means in the direction of the source of the light rays.

2. A highway retroreflecting marker as set forth in claim 1 further comprising joining means, and wherein said base and said cap are each of unitary construction and said joining means joins said base and said cap together so as to form a substantially air-tight seal therebetween.

3. A highway retroreflecting marker as set forth in claim 2 wherein said cap has a stepped construction formed by a plurality of spaced steps, said redirecting means is mounted in said cap in juxtaposed relation to 16 said plurality of spaced steps, said base includes a bottom wall, said retroreflecting means is mounted on said bottom wall, and said joining means joins said base and said cap together with said base partially inserted in said cap.

4. A highway retroreflecting marker as set forth in Claim 3 further comprising vent means formed in said side wall of said base to enable water vapor to be transmitted from the interior to the exterior of said base.

5. A highway retroreflecting marker as set forth in claim 2 wherein said cap has a substantially rectangular configuration, said redirecting means is mounted in said cap, said base includes a bottom wall, said retroreflecting means is mounted on said bottom wall, and said joining means joins said base and said cap together with said base partially inserted in said cap.

6. A highway retroreflecting marker as set forth in claim 2 wherein said cap has a substantially pyramidi cal configuration, said redirecting means is mounted in said cap, said base includes a bottom wall, said retrore- 4 flecting means is mounted on said bottom wall, said joining means joins said base and said cap together with said cap partially inserted in said base.

7. A highway retroreflecting marker as set forth in claim 2 wherein said cap includes a plurality of layerlike portions, said redirecting means is mounted in said cap in juxtaposed relation to said plurality of layer-like portions, said base includes a bottom wall, said retroreflecting means is mounted on said bottom wall, and said joining means joins said base and said cap together with said cap partially inserted in said base.

8. A highway retroreflecting marker as set forth in claim 1 wherein said base and said cap are each of unitary construction, said cap has a dome configuration, said redirecting means is mounted in said cap, said base includes a bottom wall, said retroreflecting means is mounted on said bottom wall, and said base and said cap are joined together with said base partially inserted in said cap.

9. A highway retroreflecting marker as set forth in claim 8 furthur comprising spring means supported in said base for biasing said cap to an undepressed condition.

10. A highway retroreflecting marker as set forth in claim 1 wherein said base comprises a canister portion having a substantially cylindrical configuration consisting of a relatively rigid side wall and a bottom wall, a stand having a plurality of outwardly extending flexible arms, and means for affixing said canister portion to said stand.

11. A highway retroreflecting marker as set forth in claim 1 wherein said redirecting means comprises prism means operable for reflecting the light rays to said retroreflecting means.

12. A highway retroreflecting marker as set forth in claim 1 wherein said redirecting means comprises prism means operable for refracting the light rays to said retroreflecting means.

13. A highway retroreflecting marker as set forth in claim 1 wherein said cap includes at least one face having a planar configuration, and said redirecting means is mounted in said cap in juxtaposed relation to said one face of said cap.

14. A highway retroreflecting marker as set forth in cliam 13 wherein said retroreflecting means is supported in said housing at an angle to the major axis of said housing. I

15. A highway retroreflecting marker comprising: a housing including a depressible member, a rigid member and means mounting said depressible member to said rigid member to form a substantially air-tight seal therebetween; said depressible member formed of wear-resistant resilient material, and having redirecting means supported thereon operable to redirect light received thereby; said rigid member including at least one wall having an opening therein; said opening being located in juxtaposed relation to said depressible member; and retoreflecting means supported in said rigid member in a position to receive through said opening of said rigid member the light directed from said redirecting means and for retroreflecting the light back through said opening to said redirecting means to cause the light to be directed therefrom back in the direction of the source thereof.

16. A highway retroreflecting marker as set forth in claim wherein said depressible member has a stepped construction formed by a plurality of spaced steps, said redirecting means is supported on said depressible member in juxtaposed relation to said plurality of spaced steps, said rigid member further includes a bottom wall, said retroreflecting means is supported on said bottom wall, and said depressible member is mounted to said rigid member with said rigid member partially inserted into said depressible member.

17. A highway retroreflecting marker as set forth in claim 15 wherein said depressible member includes at least one face having a planar configuration, said redirecting means is supported on said depressible member in juxtaposed relation to said one face, said retroreflecting means is supported in said rigid member at an angle to the major axis of said housing, and said depressible member is mounted to said rigid member with said rigid member partially inserted into said depressible member.

Claims

1. A highway retroreflecting marker comprising; a housing having a base and a resiliently depressible cap projecting upwardly therefrom, at least said cap being formed from a relatively wearresistant synthetic resin, said cap being substantially sealingly engaged with said base, and retroreflecting means supported in said housing, said cap having a redirecting means which is transparent to enable light rays to pass therethrough and which redirects the light rays striking said redirecting means to an angle of less than 30* to the perpendicular to the plane of said retroreflecting means, said housing being adapted for positioning of said base thereof and said cap thereof relative to a road surface so that light rays striking said redirecting means are redirected within said housing to said retroreflecting means, then are retroreflected from said retroreflecting means to said redirecting means, and thereafter are directed back from said redirecting means in the direction of the source of the light rays.

3. A highway retroreflecting marker as set forth in claim 2 wherein said cap has a stepped construction formed by a plurality of spaced steps, said redirecting means is mounted in said cap in juxtaposed relation to said plurality of spaced steps, said base includes a bottom wall, said retroreflecting means is mounted on said bottom wall, and said joining means joins said base and said cap together with said basE partially inserted in said cap.

6. A highway retroreflecting marker as set forth in claim 2 wherein said cap has a substantially pyramidical configuration, said redirecting means is mounted in said cap, said base includes a bottom wall, said retroreflecting means is mounted on said bottom wall, said joining means joins said base and said cap together with said cap partially inserted in said base.

7. A highway retroreflecting marker as set forth in claim 2 wherein said cap includes a plurality of layer-like portions, said redirecting means is mounted in said cap in juxtaposed relation to said plurality of layer-like portions, said base includes a bottom wall, said retroreflecting means is mounted on said bottom wall, and said joining means joins said base and said cap together with said cap partially inserted in said base.

14. A highway retroreflecting marker as set forth in cliam 13 wherein said retroreflecting means is supported in said housing at an angle to the major axis of said housing.

16. A highway retroreflEcting marker as set forth in claim 15 wherein said depressible member has a stepped construction formed by a plurality of spaced steps, said redirecting means is supported on said depressible member in juxtaposed relation to said plurality of spaced steps, said rigid member further includes a bottom wall, said retroreflecting means is supported on said bottom wall, and said depressible member is mounted to said rigid member with said rigid member partially inserted into said depressible member.