CA2672802A1

CA2672802A1 - Depressible pavement marker

Info

Publication number: CA2672802A1
Application number: CA002672802A
Authority: CA
Inventors: Victor Vettese
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-07-23
Filing date: 2009-07-23
Publication date: 2009-10-07
Also published as: WO2011009189A1

Abstract

A depressible, self-contained, solar-powered, pavement embedded marker capable of withstanding the impact of a snowplow blade or a vehicle tire by retracting below the surface of the pavement while providing effective delineation of traffic lanes. The pavement marker has a housing, a core assembly mounted in the housing, a light assembly mounted to the core assembly, and a plate disposed at the top of the core assembly to protect the core assembly and to deflect the core assembly downward into the housing in response to forces applied to the plate. The pavement marker is disposed within a cavity of the pavement of a highway or roadway. A resilient, elastic, compressible, liquid-impervious mass is disposed between the core assembly and the housing filling entirely the space therebetween to provide a seal during the movement of the core assembly relative to the housing. The resilient mass is also disposed between the housing and the walls of the cavity in the pavement to provide added resilience to the marker.

Description

DEPRESSIBLE PAVEMENT MARKER
TECHNICAL FIELD

The invention relates to markers for mounting in a cavity of a pavement of a highway or roadway, or in a cavity of another hard surface, and more specifically to depressible, snowplowable pavement markers with means for preventing contamination of the marker.

BACKGROUND AND PRIOR ART

A series of pavement markers are often spaced along a highway or roadway for guiding vehicles into orderly lanes to create efficient traffic flow patterns and maintain a safe spacing of vehicles. Pavement markers are more desirable than the usual painted dividing lines because such pavement markers are more visible to a driver over a greater distance and will function better in many instances where painted traffic lines are seen by a driver only with difficulty such as on wet roadways, snow covered roadways or in fog.

The prior known pavement markers are typically available in two forms - the surface mount pavement markers secured directly to the pavement surface or the embedded pavement markers positioned within a cavity in the pavement. The surface mount pavement markers are more widely utilized in warmer climates where the pavement markers would not be subject to the strikes of a snowplow blade. The embedded pavement markers are utilized in the regions where ordinary winter snowfalls require periodic snowplowing of roads. Typically, the Page 1 of 53 embedded pavement markers are installed into a cavity of the pavement and have a housing and a portion that extends upwardly from the housing above the surface of the pavement. This extended portion of the embedded pavement marker carries an illuminator or reflector sufficiently above the surface of the pavement so that rainwater will not cover the illuminator or reflector. The reflector will reflect light from vehicle headlights back to the driver making the pavement markers clearly visible. In the case of the illuminator, light from the illuminator is beamed toward the driver also making the pavement markers clearly visible.

Although such embedded pavement markers extend above the surface of the pavement, they are typically designed to be depressed into the pavement by strikes of a snowplow blade or a vehicle wheel. A bevelled upper surface is typically formed on the embedded pavement marker extension to facilitate the depression of the pavement marker. The bevelled upper surface provides an inclined surface across which a snowplow blade or a wheel moves thereby depressing the extending portion of the pavement marker downwardly into the housing.

The depressible embedded pavement marker should be able to withstand numerous strikes by snowplow blades and vehicle wheels without any damage to the marker or any detrimental effect upon the snowplow blade or wheel.

Page 2 of 53 Typically, depressible pavement markers operate on a cylinder and piston principle, with the piston part carrying a reflector element or an illuminator. The cylinder part, however, forms a cavity which is prone to collecting rainwater or snowmelt water and subsequent freezing in cold weather. Such freezing of accumulated water may render the piston type pavement marker inoperable.
Additionally, the movement of the piston in the housing precipitates collection and accumulation of highway dirt and grit within the marker and specifically between the moving surfaces which can hinder the retraction of the piston. The cavity below the piston can also collect dirt which will produce the same effect as ice.

Another group of depressible embedded pavement markers utilizes foam rubber to permit the deflection and depression of the extended portion of the pavement marker. Unfortunately, over a period of time and upon exposure to the deteriorating effects of sunlight and weather elements, foam rubber has a tendency to crack and break eventually resulting in the total distraction of at least the extended portion of the embedded pavement marker. Another problem is the torquing effect of the snowplow blades engaging the pavement marker.

Depressible embedded markers described in US patents Nos. 4,955,982, 5,074,706 and 5,302,048 assigned to Olympic Machines, Inc., attempt to solve some of the above-mentioned problems concomitant with the weather and road conditions. The markers use a compression assembly situated within the housing and under the piston element. However, these markers still employ a piston Page 3 of 53 sliding with a close fit within a housing or retainer, and it is this piston-housing interface that is prone to gathering dust, dirt and grime, leading potentially to the loss of operability of the marker.

There is still a need for a depressible pavement marker wherein the above-described contamination problems are reduced or eliminated.

SUMMARY OF THE INVENTION

According to one aspect of the invention, there is provided a pavement marker comprising:

a core movably mounted within a cavity formed within a pavement, the cavity having a bottom and side walls, the core comprising side walls and an upper end, the side walls of the core and the side walls of the cavity defining a generally annular space allowing for a lateral and vertical movement of the core within the cavity, a lighting unit or assembly affixed at the upper end of the core, a resilient, compressible and Iiquid-impervious mass disposed in the annular space to prevent ingress of liquids and solids between the core and the cavity, and a spring means associated with the core and the cavity, the spring means operable between an extended, or main, position in which the lighting assembly protrudes above the level of the pavement, and a depressed, or displaced, position Page 4 of 53 in which the core with the lighting assembly retracts into the cavity below the level of the pavement.

In one embodiment, the marker comprises engaging means formed on the side walls of the core facing the cavity, for engaging the mass with the core. The engaging means may comprise at least one circumferential groove.

The core may comprise retaining means formed on the side walls facing the cavity, for restricting rotation of the core relative to the cavity. The retaining means may be selected from vertical grooves, slots, ribs, slots and splines.

The spring means may comprise a resilient, compressible mass disposed in a space between the cavity and the core. The mass may be liquid-impervious. In an embodiment of the invention, the spring means may be a conventional spring such as a helical spring.

In one embodiment, the marker comprises a resilient, compressible, liquid-impervious mass disposed in the entire space between the core and the pavement cavity.

In an embodiment, the lighting assembly or unit is a self-illuminating light assembly. In another embodiment, the lighting assembly is a light reflecting unit.
Page 5 of 53 According to another aspect of the invention, there is provided a pavement marker comprising:

a housing adapted to be mounted within a cavity formed within a pavement, the cavity having a bottom and side walls, said housing having side walls and an open top end, the housing dimensioned to be fully retractable into the cavity, the side walls of the housing and the side walls of the cavity defining a first generally annular space allowing for a lateral and vertical movement of the housing within the cavity, a core mounted within the housing, the core comprising side walls and an upper end, the side walls of the core and the side walls of the housing defining a second generally annular space allowing for a lateral and vertical motion of the core within the housing, a lighting assembly affixed at the upper end of the core, a resilient, compressible and liquid-impervious mass disposed in the first annular space to prevent ingress of liquid between the housing and the cavity, a resilient, compressible and liquid-impervious mass disposed in the second annular space to prevent ingress of liquid between the core and the housing, and a spring means disposed in the cavity under the core, the spring means operable between an extended, or main, position in which the lighting assembly protrudes above the level of the pavement, and a depressed position in which the core with the lighting assembly retracts into the cavity below the level of the pavement.

Page 6 of 53 The spring means may comprise a resilient, compressible mass disposed in a space between the housing and the core. The mass may be liquid-impervious. In an embodiment of the invention, the spring means may be a conventional spring such as a helical spring. A resilient, compressible, liquid-impervious mass may be disposed in the entire space between the cavity and the housing and operate as a spring means as well as a seal of the space between the cavity and the housing.
The same or similar mass may be disposed in the entire space between the housing and the core to operate as a seal and as a spring means.

In an embodiment, the lighting assembly is a self-illuminating light assembly.
In another embodiment, the lighting assembly is a light reflecting unit.

In one embodiment of this aspect of the invention, the marker comprises first engaging means formed on the side walls of the housing facing the cavity, second engaging means formed on the side walls of the housing facing the core, and third engaging means formed on the side walls of the core facing the housing, for engaging the mass disposed in the respective spaces. The engaging means may comprise at least one circumferential groove.

In an embodiment of this aspect of the invention, the marker comprises retaining means formed on the side walls of the housing facing the core, and on the side walls of the core facing the housing, for restricting rotation of the core relative to the housing.

Page 7 of 53 The housing may comprise retaining means formed on the side walls facing the cavity, for restricting rotation of the housing relative to the cavity.

The retaining means may comprise vertical grooves, fins, ribs, slots and splines.

In an embodiment, the core of the pavement marker has a self-illuminating light assembly, consisting of a solar cell, photo switch, capacitor, light emitting diodes, and control circuitry. The photo switch activates and deactivates control circuitry in response to ambient light conditions. During the daylight light hours, the photo switch deactivates control circuitry and through the solar cell recharges the capacitor. When the ambient light drops below a certain predetermined level, the light switch activates the control circuitry. The control circuitry draws the electric power from the capacitor. The control circuitry operates a timing device that causes the light emitting diodes of the light assembly to blink in a direction of the approaching traffic. In an alternative embodiment, the pavement marker is void of the energy source and the means by which it is recharged, including the light emitting diodes, and instead provides light retro-reflective elements that return light toward the source of oncoming light which is emitted from the headlights of an oncoming vehicle.

In an embodiment of the invention, the self-illuminating core assembly of the pavement marker extends above the level of the pavement so that the light transmitted by the light emitting diodes can be seen. When a snowpiow or a Page 8 of 53 vehicle wheel strikes the extended self-illuminating core assembly, the core assembly depresses from the extended position above the surface of the pavement into the depressed position in the housing. The resilient mass compresses and absorbs the forces encountered during depression of the core assembly to reduce fatigue damage. The resilient mass prevents a permanent displacement of the core assembly from the extended position under the forces applied by the snowplow blade or vehicle wheel. Once the snowplow blade or wheel passes the pavement marker, the core assembly, as the result of biasing action of the resilient mass, "pops up" back to the original extended position above the surface of the pavement so that the light transmitted by the light emitting diodes can be seen.

While in the embodiments illustrated the housing and the core are indicated as cylindrical, it is conceivable to design an equivalent housing and/or a core assembly with a polygonal cross-section.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in more detail by way of the following description to be taken in conjunction with the accompanying drawings, which drawings form a part of the specification and in which like numerals depict like parts in the several views. It is noted, however, that the appended drawings illustrate only a preferred embodiment of the invention and are therefore not to be considered limiting of its scope, for the invention may admit of other equally effective embodiments.

Page 9 of 53 FIG 1 is a partially broken away perspective view of the pavement marker installed in a pavement cavity;

FIG 2 is an exploded view of the pavement marker;

FIG 3 is a top elevated view of the pavement marker installed in a pavement cavity;

FIG 4 is a vertical cross-section of the pavement marker along the line 4- 4 of the FIG 3;

FIG 5 is a vertical cross-section of the pavement marker along the line 5 - 5 of the FIG 3;

FIG 6 is a perspective view of the pavement marker;

FIG 7 is a top perspective view of the housing of the pavement marker;

FIG 8 is a bottom perspective view of the housing of the pavement marker;
FIG 9 is a vertical elevated view of the housing of the pavement marker;
Page 10 of 53 FIG 10 is a vertical cross-section of the housing of the pavement marker along the line 10 -10 of the FIG 9;

FIG 11 is a bottom elevated view of the housing of the pavement marker;

FIG 12 is a top perspective view of the core assembly of the pavement marker;
FIG 13 is a bottom perspective view of the core assembly of the pavement marker;
FIG 14 is a top elevated view of the core assembly of the pavement marker;

FIG 15 is a vertical cross-section of the core assembly of the pavement marker along the line 15 - 15 of FIG 14;

FIG 16 is a vertical cross-section of core assembly of the pavement marker along the line 16 -16 of the FIG 14;

FIG 17 is a bottom elevated view of the core assembly of the pavement marker;
FIG 18 is a top perspective view of the light assembly of the pavement marker;
FIG 19 is a bottom perspective view of the light assembly of the pavement marker;

Page 11 of 53 FIG 20 is a top exploded view of the light assembly of the pavement marker;
FIG 21 is a bottom exploded view of the light assembly of the pavement marker;
FIG 22 is an electrical schematic of the light assembly of the pavement marker;
FIG 23 is a top perspective view of the mylar (trademark);

FIG 24 is a bottom perspective view of the mylar (trademark);

FIG 25 is a top elevated view of the mylar (trademark);

FIG 26 is a vertical cross-section of the mylar (trademark) along the line 26 -26 of the FIG. 25;

FIG 27 is a vertical cross-section of the mylar (trademark) along the line 27 -27 of the FIG. 25;

FIG 28 is a bottom elevated view of the mylar (trademark);

FIG 29 is a top perspective view of the plate;
FIG 30 is a bottom perspective view of the plate;
Page 12 of 53 FIG 31 is a top elevated view of the plate;

FIG 32 is a vertical cross-section of the plate along the line 32 - 32 of the FIG 31;
FIG 33 is a vertical cross-section of the plate along the line 33 - 33 of the FIG 31;
FIG 34 is a partially broken away perspective view of an embodiment of the pavement marker (with light assembly) installed in a pavement cavity;

FIG 35 is a partially broken away perspective view of an embodiment of the pavement marker (with light assembly) installed in a pavement cavity;

FIG 36 is a partially broken away perspective view of an embodiment of the pavement marker (with light reflector) installed in a pavement cavity; and FIG 37 is a partially broken away perspective view of an embodiment of the pavement marker (with light reflector) installed in a pavement cavity.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A depressible, self-contained, solar-powered, pavement embedded marker (10) of the present invention is shown in the FIGS. 1 and 2. The pavement marker (10) is intended to delineate traffic lanes of a highway or roadway to assist drivers in a variety of weather conditions. The pavement marker (10) is flexibly disposed Page 13 of 53 within the cavity (16) of the pavement (12) by resilient, elastomeric, compressible, liquid-impervious mass (20) disposed around the pavement marker (10). The resilient mass (20) is compressible upon a downward force on the housing of the pavement marker (10). The pavement marker (10) has a housing (22), a core assembly (24) received in the housing (22), the mass (20) disposed between the core assembly (24) and the housing (22) to facilitate a reciprocating motion of the core assembly (24) within the housing (22) in response to the forces applied onto the core assembly (24) by surface traffic; and a light assembly (30) with light emitting diodes (236), (240), and (244) (shown on FIG. 18) which is disposed inside the core assembly (24). A transparent Mylar (trademark) cover (28) is disposed over the light assembly (30) on top of the core assembly (24) to protect the light assembly (30). A plate (26) is attached at the top of the core assembly (24) to protect the core assembly (24), the light assembly (30) and the transparent mylar cover (28) and to deflect the core assembly (24) downward into the housing (22) in response to forces applied to the plate (26).

The housing (22) of the pavement marker (10) is shown in FIGS. 1 - 11. The housing (22) defines a container having an external bottom surface (48) and an external wall (34) that vertically extends from the external bottom surface (48) of the housing (22) and terminates with a top ledge (36) of the housing (22). The external wall (34) has an external circumferential groove (40). Below the external circumferential groove (40) of the housing (22) extends an external lower end portion (42) of the external wall (34). Above the circumferential groove (40) Page 14 of 53 extends an external upper end portion (38) of the external wall (34) of the housing (22). The resilient mass (20) is preferably an elastomeric material such as a closed-cell foam resin material which is shaped to fill and seal virtually the entire space between the external wall (34) of the housing (22) and the wall (18) of the pavement cavity (16). Because the resilient mass (20) fills virtually the entire space between the external wall (34) and the wall (18), there is substantially no space where excess liquid or air could be retained. The resilient mass (20) biases the housing (22) to its main position in which the top ledge (36) of the housing (22) is at the level of pavement surface (14). The resilient mass (20) is compressible upon a downward force on the housing (22) of the pavement marker (10). Under the forces created by a snowplow blade or a vehicle wheel, the housing (22) retracts into the pavement cavity (16) from the main position to a displaced position in which the top ledge (36) of the housing (22) is below the pavement surface (14) level. The external circumferential groove (40) of the housing (22) provides a mechanical lock with the resilient mass (20) thereby creating additional bonding area that facilitates return of the housing (22) to the original main position.
The resilience of the mass (20) and the mechanical lock between the resilient mass (20) and the external circumferential groove (40) prevent a permanent displacement of the housing (22) from the main position under the forces applied by a snowplow blade or vehicle wheel. Once the snowplow blade or wheel passes the pavement marker (10), the housing (22), as a result of biasing action of the resilient mass (20) and the mechanical lock between the resilient mass (20) and Page 15 of 53 the external circumferential groove (40), returns back to the original main position at which the top ledge (36) of the housing (22) is at the level of the pavement surface (14). The resilient mass (20) is compressed and expanded with the cycling of the housing (22) and therefore continuously fills virtually the entire space between the external wall (34) and the wall (18) of the pavement cavity (16) during this cycle. The resilient mass (20) prevents liquid from being retained in the pavement cavity (16) by substantially filling the entire space between the external wall (34) of the housing (22) and the wall (18) of the pavement cavity (16).
The resilient mass (20) does not allow an ingress or egress of liquid and silt which could hinder the functioning of the pavement marker (10) or could damage the marker e.g. if liquid remained in the pavement cavity (16) and froze.

The circumference of the external lower end portion (42) of the external wall (34) of the housing (22) comprises a plurality of arcuate grooves (46). Each arcuate groove (46) is paired with a fin (44) and the grooves (46) and fins (44) alternate.
The grooves (46) and the fins (44) are equally spaced on the circumference of the external lower end portion (42) of the external wall (34) of the housing (22).
The grooves (46) and the fins (44) provide a mechanical engagement with the resilient mass (20) disposed between the external wall (34) of the housing (22) and the wall (18) of the pavement cavity (16). The grooves (46) and the fins (44) create additional bonding area with the resilient mass (20) and increase latitudinal, longitudinal and torsional rigidity of the housing (22) under the forces created by Page 16 of 53 the snowplow blade or vehicle wheel and function to limit rotation of the housing (22) under these forces in the pavement cavity (16).

The housing (22) further comprises an internal bottom surface (58) and an internal wall (50) that extends from the internal bottom surface (58) and terminates with a top ledge (36) of the housing (22). The internal wall (50) of the housing (22) has an internal circumferential groove (54). Above the circumferential groove (54) is an internal upper end portion (52) of the internal wall (50). Below the internal circumferential groove (54) is an internal lower end portion (56) of the internal wall (50). The circumference of the internal lower end portion (56) of the internal wall (50) comprises a plurality of arcuate ribs (60). Each arcuate rib (60) is paired with a slot (64) and the ribs (60) and the slots (64) alternate. The arcuate ribs (60) and the slots (64) are equally spaced on the circumference of the internal lower end portion (56) of the internal wall (50).

Core Assembly The core assembly (24) of the pavement marker (10) is shown in FIGS. 1- 6 and FIGS. 12 - 17. The core assembly (24) comprises a container having an external bottom surface (76) and an external wall (66) that vertically extends from the external bottom surface (76) and terminates with a top circumferential ledge (68).
The external wall (66) has an external circumferential groove (72). Below the external circumferential groove (72) is an external bottom end portion (74) of the external wall (66). Above the circumferential groove (72) is an external top end Page 17 of 53 portion (70) of the external wall (66). The core assembly (24) has a light assembly compartment (88) in which the light assembly (30) is disposed. The light assembly compartment (88) has a bottom surface (102). The bottom surface (102) has at least two pedestals (104) and (106). The pedestals maintain a proper alignment of the light assembly (30) inside the light assembly compartment (88). The compartment (88) further comprises side walls (108) and (110), a back wall (112), and a front wall (114). The side walls (108) and (110), the back wall (112), and the front wall (114) of the light assembly compartment (88) all vertically extend from the bottom surface (102) of the light assembly compartment (88) and terminate at the light assembly compartment ledge (90). The front wall (114) of the light assembly compartment has a plurality of light cavities (96), (98), and (100).
The light cavities maintain a proper alignment of the light assembly (30) inside the light assembly compartment (88). The perimeter of the light assembly compartment ledge (90) has a light assembly compartment groove (94). The groove accommodates a hermetic seal (32) (FIG. 2) which preferably seals the light assembly compartment (88) and substantially prevents accumulation of moisture in the compartment. A light assembly compartment recess wall (92) vertically extends from the light assembly compartment groove (94). The light assembly compartment recess wall (92) terminates at a top shoulder (84) of the core assembly (24).

Page 18 of 53 The top shoulder (84) has a plurality of threaded bores (86). A top circumferential groove (82) of the core assembly (24) is disposed between the top shoulder (84) and the top circumferential ledge (68) of the core assembly (24).

It will be noted that in the preferred embodiment, the marker has a self-illuminating light assembly (30). It is within the present state of the art to replace the self-illuminating light source with a reflecting element (250) (FIGS. 36 and 37) or assembly which would reflect light radiated by vehicles, for example as described in US patent 4,995,982.

The core assembly (24) has a plate (26) attached to the top shoulder (84) of the core assembly (24) in the manner described below. The plate (26) is shown on the FIGS. 29 - 33. The plate has a top surface (118) and a bottom surface (120).
The top surface (118) and the bottom surface (120) are connected by a circumferential side wall (122). The bottom end (126) of the circumferential side wall (122) borders the bottom surface (120) of the plate (26). The top end (124) of the circumferential side wall (122) borders the top surface (118) of the plate (26).
The top surface (118) of the plate (26) comprises bevelled ramps (128) and (130).
The top surface (118) also comprises level ramps (132) and (134). The bevelled ramps (128) and (130) are symmetrically disposed on the top surface (118) of the plate (26) across the longitudinal plane of the pavement marker (10). The bevelled ramps (128) and (130) have inclined surfaces (136) and (138) with inclined plane across as shown in FIG. 32 and FIG. 33. The inclined surface (136) of the Page 19 of 53 bevelled ramp (128) extends from the peripheral circumference of the plate (26) toward the centre of the plate (26) and terminates with a bevelled ramp side wall (144). The peripheral circumference of the plate (26) is the lowest point of the inclined surface (136) of the bevelled ramp (128). The side wall (144) of the bevelled ramp (128) is the highest point of the inclined surface (136) of the bevelled ramp (128). The inclined surface (138) of the bevelled ramp (130) symmetrically extends from the circumference of the plate (26) toward the centre thereof and terminates with a bevelled ramp side wall (146). The bevelled ramps (128) and (130) of the plate (26) facilitate the depression of the core assembly (24) into the housing (22) of the pavement marker (10). When a snowplow blade or vehicle wheel moves across the inclined surfaces (136) and (138) of the bevelled ramps (128) and (130), the snowplow or wheel depresses the plate (26) and the core assembly (24) downwardly into the housing (22) of the marker (10).

The top surface (118) of the plate (26) also comprises level ramps (132) and (134).
The level ramps (132) and (134) are symmetrically disposed on the top surface (118) of the plate (26) across the latitudinal plane of the pavement marker (10).
The level ramps (132) and (134) are symmetrically positioned between bevelled ramps (128) and (130) as shown on the FIGS. 1, 2, 3 and 29. The level ramp (132) extends from the circumference of the plate (26) toward the centre of the plate (26) and terminates with a level ramp side wall (148). The level ramp (134) symmetrically extends from the circumference of the plate (26) toward the centre of the plate (26) and terminates with a level ramp side wall (150). The side wall Page 20 of 53 (144) of the bevelled ramp (128), the side wall (148) of the level ramp (132), side wall (146) of the bevelled ramp (130), and the side wall (146) of the level ramp (134) form a rectangular window (152) of the plate (26). The perimeter of the window (152) is adapted to accommodate the transparent mylar (28).

Bevelled ramps (128) and (130) have a plurality of recesses (154). Level ramps (132) and (134) also have a plurality of recesses (154). The recesses (154) house bolts (156). The bolts (156) fasten the plate (26) to the top shoulder (84) of the core assembly (24) by threadably engaging the threaded bores (86) disposed on the top shoulder (84) of the core assembly (24). The bottom surface (120) of the plate (26) has a circumferential ledge (158) extending generally vertically from the bottom surface (120) of the plate (26). The circumferential ledge (158) of the plate (26) is adapted to fit inside the top circumferential groove (82) of the core assembly (24). The top circumferential groove (82) of the core assembly provides a mechanical lock with the circumferential ledge (158) of the plate (26) thereby creating additional bonding area between the plate (26) and the core assembly (24) of the marker (10). The mechanical lock between the top circumferential groove (82) of the core assembly (24) and the circumferential ledge (158) of the plate (26) increases latitudinal, longitudinal and torsional rigidity of the plate (26) under the forces created by a snowplow blade or a vehicle wheel and preferably limit movement of the plate (26) under these forces.

Page 21 of 53 The circumferential side wall (122) of the plate (26) is substantially flush with the top end portion (70) of the external wall (66) of the core assembly (24) when the plate (26) is fastened to the top shoulder (84) of the core assembly (24) as shown on FIG. 4 and FIG. 5. The top end (124) of the side wall (122) of the plate (26) is substantially level with the top ledge (36) of the housing (22) of the pavement marker (10) when the plate (26) is fastened to the top shoulder (84) of the core assembly (24) of the pavement marker (10) as shown in FIG. 4 and FIG. 5.

The resilient mass (20) fills virtually the entire space between the external wall (66) of the core assembly (24) and the internal wall (50) of the housing (22) of the pavement marker (10). As a result, there is substantially no space where excess liquid or air could be retained. The resilient mass (20) biases the core assembly (24) to its extended position. In the extended position, the bevelled ramps (128) and (130) of the plate (26) are above the level of the pavement surface (14).
The resilient mass (20) is compressible upon a downward force on the plate (26) of the pavement marker (10). Under the forces applied to the bevelled ramps (128) and (130) by a snowplow blade or vehicle wheel, the plate (26) moves the core assembly (24) from the extended position to the depressed position in which the core assembly (24) is depressed downwardly into the housing (22). At the depressed position, the bevelled ramps (128) and (130) of the plate (26) are substantially at or below the top ledge (36) of the housing (22) and are substantially at or below the level of pavement surface (14), whereby snowplow Page 22 of 53 blade or vehicle wheel may move over the pavement marker (10) without damaging the core assembly (24).

The internal circumferential groove (54) of the housing (22) of the pavement marker (10) and the external circumferential groove (72) of the core assembly (24) provide a mechanical engagement with the resilient mass (20) thereby creating additional bonding area. The biasing force of the resilient mass (20) and the mechanical lock between the resilient mass (20), the internal circumferential groove (54) of the housing (22) and the external circumferential groove (72) of the core assembly (24) prevent a permanent displacement of the core assembly (24) from the extended position under the forces applied by a snowplow blade or a vehicle wheel. Once the snowplow blade or wheel passes the pavement marker (10), the core assembly (24), as the result of biasing action (resilience) of the resilient mass (20) and the mechanical lock between the resilient mass (20), the internal circumferential groove (54) of the housing (22) and the external circumferential groove (72) of the core assembly (24), returns back to the original extended position at which the bevelled ramps (128) and (130) of the plate (26) are above the level of the surface (14) of the pavement (12). The resilient mass (20) is compressed and expanded with the cycling of the core assembly (24) of the pavement marker (10), and therefore the resilient mass (20) continuously fills virtually the entire space between the external wall (66) of the core assembly (24) and the internal wall (50) of the housing (22) during this cycle. The resilient mass (20) prevents liquid from being retained in the space between the external wall (66) Page 23 of 53 of the core assembly (24) and the internal wall (50) of the housing (22) by substantially filling the entire space between the external wall (66) and internal wall (50).

The resilient mass (20) does not allow an ingress and egress of liquid and silt materials which could hinder the functioning of the marker (10) or could damage it in the case when liquid would remain and freeze in the space between the core assembly (24) and the housing (22).

The circumference of the external bottom end portion (74) of the external wall (66) of the core assembly (24) comprises a plurality of equally spaced arcuate grooves (80) and fins (78). Fins (78) alternate with the grooves (80). Each arcuate groove (80) of the core assembly is positioned above the internal arcuate rib (60) of the housing (22) when the core assembly (24) is installed in the housing (22). The radius of curvature of the internal rib (60) of the housing (22) is preferably slightly smaller than the radius of curvature of the arcuate groove (80) of the core assembly (24). Each fin (78) of the core assembly (24) matingly fits inside the slot (64) of the housing (22) when the core assembly (24) is installed in the housing (22). The arcuate grooves (80) of the core assembly (24) at all times slidably engage the arcuate ribs (60) of the housing (22). The fins (78) of the core assembly (24) at all times slidably engage the slots (64) of the housing (22).
The slidable engagement between the arcuate ribs (60) of the housing (22) and arcuate grooves (80) of the core assembly (24) and the slidable lock between the Page 24 of 53 fins (78) of the core assembly (24) and the slots (64) of the housing (22) increases latitudinal, longitudinal and torsional rigidity of the core assembly (24) under the forces created by the snowplow blade or vehicle wheel and limit rotation of the core assembly (24) under these forces in the housing (22) of the marker (10).

Mylar The transparent Mylar (trademark) element (28) is shown in FIGS. 23 - 28. The mylar is made of an abrasion resistant plastic. The mylar (28) comprises a base (160) and an extension (162). The mylar base (160) has a top surface (164) and a bottom surface (166). The top surface (164) of the base (160) has a ledge (168).
The bottom surface (166) of the mylar base (160) and the top surface (164) of the mylar base are connected by a side wall (170). The extension (162) has a top surface (172) and a side wall (176). The side wall (170) of the extension (162) vertically extends from the ledge (168) of the mylar base (160) and terminates with the top surface (172) of the mylar extension (162). The top surface (172) of the mylar extension (162) has a plurality of bumps (174). The bumps (174) preferably prevent the top surface (172) of the extension (162) from coming in to a direct contact with abrasive surfaces and abrasive particles thereby preferably preserving the transparency of the mylar (28). The extension (162) has a clear window (178).

The clear window (178) is sloping from the top surface (172) of the extension (162) toward the top surface (164) of the base (160).

Page 25 of 53 The mylar (28) has diode cavities (180), (182) and (184) which are shown on FIGS. 28 - 30. Each of the diode cavities (180), (182) and (184) comprises a front edge (186), a back edge (188), and side edges (190) and (192). The light cavities (180), (182) and (184) extend from the bottom surface (166) of the mylar base (160) toward the clear window (178) of the mylar extension (162). The diode cavities (180), (182) and (184) house the light emitting diodes (236), (240), and (244) of the light assembly (30).

The mylar (28) is positioned above the light assembly compartment (88) as shown in FIG. 1, FIG. 4 and FIG. 5. The bottom surface (166) of the mylar base (160) abuts the light assembly compartment ledge (90). The side wall (170) of the mylar base (160) abuts the light assembly compartment recess wall (92). The window (152) of the plate (26) is positioned over the extension (162) of the mylar (28). The mylar extension (162) preferably extends through the plate window (152). The ledge (168) of the mylar base (160) abuts the bottom surface (120) of the plate (26).

Light Assembly The light assembly (30) of the pavement marker is shown in FIGS. 18 - 21. The light assembly (30) comprises a light assembly base (194) and a light assembly extension (196). The light assembly base (194) is a hollow container having a bottom surface (202) and a top surface (204). Inside the light assembly base (194) is a light assembly base circuitry compartment (212). The bottom surface Page 26 of 53 (202) and the top surface (204) of the light assembly base (194) are connected by a light assembly base side wall (206). The light assembly (30) also comprises a light assembly pad (200). The light assembly pad (200) is preferably made from closed cell foam. The light assembly pad (200) is attached to the bottom surface (202) of the light assembly base (194) by a bonding agent. The light assembly pad (200) supports the light assembly (30) in the light assembly compartment (88) of the core assembly (24) of the marker (10). The light assembly pad (200) and the pedestals (104) and (106) facilitate alignment of the light assembly (30) inside the light assembly compartment (88) of the core assembly (24).

The light assembly extension (196) is a hollow container having a bottom surface (216) and a top surface (214). Inside the light assembly extension (196) is a light assembly extension circuitry compartment (222). The bottom surface (216) and the top surface (214) of the light assembly extension (196) are connected by a light assembly extension side wall (218). The light assembly (30) has a solar sell (230).
The solar cell (230) is disposed on the top surface (214) of the light assembly extension (196). The solar energy absorbing side of the solar cell (230) is facing the transparent mylar (28) positioned above the light assembly (30). The solar cell (230) is connected to a light assembly circuit board (228). The light assembly extension (196) also has a light assembly extension ramp (220). The ramp is generally sloping forward from the top surface (214) of the light assembly extension (196) toward the bottom surface (216) of the light assembly extension (196). The light assembly extension ramp (220) has apertures (238), (242), and Page 27 of 53 (246). The light emitting diodes (236), (240) and (244) are protruding through the apertures (238), (242), and (246). The apertures (238), (242), and (246) support and align the light emitting diodes (236), (240), and (244) in the light assembly (30). The bottom surface (216) of the light assembly extension (196) has a plurality of threaded bores (224). The bottom surface (202) of the light assembly base (194) has a plurality of recesses (208). The recesses (208) of the light assembly base (194) house bolts (210). As shown on the FIGS. 20 and 21, the bolts (210) extend through the light assembly base (194) and threadably engage the threaded bores (224) on the bottom surface (216) of the light assembly extension (196). When assembled, the light assembly base circuitry compartment (212) and the light assembly extension circuitry compartment (222) comprise a light assembly circuitry compartment (226) that houses the light assembly circuitry board (228) and a capacitor (234).

The electrical schematic of the light assembly (30) is shown in FIG. 22. The electrical schematic of the light assembly (30) comprises the solar cell (230); a photo switch (232) preferably mounted as a part of the solar cell (230); three light emitting diodes (236), (240), and (244); a timer chip (248); and the capacitor (234) which supplies electric power to the timer chip (248). The solar cell (230), the photo switch (232), the three light emitting diodes (236), (240) and (244), and the capacitor (234) all are connected to the light assembly circuitry board (228).
Light entering through the transparent mylar (28) supplies solar energy to the solar cell (230). The solar cell (230) is a series of photocells arranged to deliver electric Page 28 of 53 current and charge the capacitor (234) during the daylight hours. The light assembly (30) in the preferred embodiment of the present invention requires about three volts to operate. Additional capacitors may be added in series to the capacitor (234). The additional capacitors would increase current while keeping the same low voltage.

The electrical schematic of the light assembly (30) shows a timer chip (248).
The timer chip is generally known as a 555 timer chip. The chip (248) is an integrated circuit and usually has eight terminals, labelled 1 - 8.

The operating logic of the timer chip (248) depends on the voltages applied to the terminals of the timer chip (248). The electrical schematic of the light assembly (30) also shows a resistor R1 connected between the terminals 4 and 7 of the timer chip (248), and a resistor R2 connected between the terminal 7 and the terminals 6 and 2 of the timer chip (248). A capacitor C1 is connected between the terminal 2 and the ground terminal 1 of the timer chip (248). The terminal 3 of the timer chip (248) is connected to the light emitting diodes (236), (240) and (244). The light emitting diodes (236), (240), and (244) are connected in parallel between the terminal 3 and the ground terminal 1 of the timer chip (248). The terminal 8 of the timer chip (248) receives electric power from the capacitor (234) through the photo switch (232).

Page 29 of 53 During daylight hours, when the photo switch (232) receives light, the photo switch (232) is in OFF position and the timer chip (248) is disconnected from the electric power supply provided by the capacitor (234). Without the electric power supply, the timer chip (248) stops to operate and stops to supply impulses of the electric power to the light emitting diodes (236), (240), and (244). During the night, or when the ambient light drops below a certain predetermined level, the photo switch (232) does not receive enough light and is in ON position thereby connecting the timer chip (248) to the electric power supply provided by the capacitor (234).
The timer chip (248) begins to operate and supplies impulses of the electric power to the light emitting diodes (236), (240), and (244) causing them to blink with a predetermined frequency.

The solar cell (230) is connected in parallel with the capacitor (234). During the daylight hours when the photo switch (232) is in OFF position and the circuit is open, the solar cell (230) charges the capacitor (234). The solar cell (230) supplies the capacitor (234) with electric current at a voltage of about three volts.
During the night hours when the photo switch (232) is in ON position and the circuit is closed, the capacitor (234) supplies the electrical power to the timer chip (248) to operate the light emitting diodes (236), (240), and (244). Under rainy or foggy conditions occurring during daylight, and once the ambient light drops below certain predetermined level, the photo switch (232) will close the circuit and will energize the timer chip (248). The photo switch (232) preferably has a high enough threshold that the timer chip (248) will not operate during periods when Page 30 of 53 any significant light falls on the solar cell (230) of the light assembly (30).
Preferably, the photo switch (232) should close the circuit only under the darkest conditions likely to be encountered, in order to conserve charge of the capacitor (234).

It is preferred to set the oscillation frequency of the timer chip (248) to have a duty cycle from about 5% to about 15% with frequency of energizing of the light emitting diodes (236), (240), and (244) less than 1 Hz. A low duty cycle can be used where the time during which the light emitting diodes (236), (240), and (244) will be emitting light for 0.050 seconds and off for duration of 0.779 seconds before being turned on again. This corresponds to a duty cycle of 6%. I high duty cycle of 15%
would energize the light emitting diodes (236), (240), and (244) for 0.124 seconds followed by an off time of 0.705 sec. A medium duty cycle of 12% would energize the light emitting diodes (236), (240), and (244) for 0.107 seconds followed by an off time of 0.722 seconds. A low duty cycle can trigger the light emitting diodes (236), (240), and (244) for about 0.124 seconds every 0.607 seconds. In this low duty cycle the values of the resistors in the circuit of the FIG. 22 are R1=120 kilo ohm, R2=33 kilo ohm, and capacitor C1=4.7 pF. With these values in the circuit defining the duty cycle, the only variable left to explore is that of the storage capacitor (234). The capacitance of the capacitor (234) for evenly distributed discharge for the three light emitting diodes (236), (240), and (244) is given in the table below.

Page 31 of 53 Capacitance and Discharge Time for a 0.607 Second Cycle Capacitance (Farads) Discharge Time (Hours) 5.00 3.0 6.67 4.0 10.0 6.0 13.5 8.0 20.0 12.0 Once the light assembly (30) is assembled and installed in the light assembly compartment (88) of the core assembly (24), foam (116) may be gently added to the light assembly compartment (88) of the core assembly (24) of the pavement marker (10). The foam (116) is preferably an elastomeric material such as a closed cell foam material which is shaped to fill virtually the entire space between the light assembly compartment walls (108), (110), (112) and (114) and the light assembly (30). Because the closed cell foam (116) fills virtually the entire space between the light assembly compartment walls (108), (110), (112), and (114) and the light assembly (30), there is substantially no space where excess moisture or air could be retained. The closed cell foam (116) substantially isolates the light assembly (30) from ionic constituents, moisture or other deleterious components.

Page 32 of 53 According to another embodiment of the invention shown in FIG. 34, the pavement marker (10) comprises a core assembly (24) movably mounted within a cavity (16) formed within the pavement (12). The core assembly (24) has the light assembly (30) affixed at the upper end thereof. The cavity (16) has a wall (18). The core assembly (24) has a side wall (66). The side wall (66) and the wall (18) of the pavement cavity (16) define a generally annular space allowing for a lateral and vertical movement of the core assembly (24) within the pavement cavity (16).
The resilient, compressible and liquid-impervious mass (20) is disposed in the annular space between the side wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16). The resilient mass (20) fills virtually the entire space between the external wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16). As a result, there is substantially no space where excess liquid or air could be retained. The resilient mass (20) biases the core assembly (24) to its extended position. In the extended position, the bevelled ramps (128) and (130) of the plate (26) are above the level of the pavement surface (14).
The resilient mass (20) is compressible upon a downward force on the plate (26) of the pavement marker (10). Under the forces applied to the bevelled ramps (128) and (130) by a snowplow blade or vehicle wheel, the plate (26) moves the core assembly (24) from the extended position to the depressed position in which the core assembly (24) is depressed downwardly into the pavement cavity (16). At the depressed position, the bevelled ramps (128) and (130) of the plate (26) are substantially at or below the level of pavement surface (14), whereby snowplow blade or vehicle wheel may move over the pavement marker (10) without Page 33 of 53 damaging the core assembly (24) and the light assembly (30). The resilient mass (20) is compressed and expanded with the cycling of the core assembly (24) of the pavement marker (10), and therefore the resilient mass (20) continuously fills virtually the entire space between the external wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16) during this cycle. The resilient mass (20) prevents liquid from being retained in the space between the external wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16) by substantially filling the entire space between the external wall (66) and the wall (18). As shown in FIG. 34, a helical spring (254) functions either as an alternative to the resilient mass (20), or in combination with the resilient mass (20).

According to another embodiment of the invention shown in FIG. 35, the pavement marker (10) comprises the core assembly (24) movably mounted within the cavity (16) formed within the pavement (12). The cavity (16) has walls (18). The core assembly (24) has a side wall (66). The side wall (66) and the wall (18) of the pavement cavity (16) define a generally annular space allowing for a lateral and vertical movement of the core assembly (24) within the pavement cavity (16).
The resilient, compressible and fiquid-impervious mass (20) is disposed in the annular space between the side wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16). The resilient mass (20) fills virtually the entire space between the external wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16). As a result, there is substantially no space where excess Page 34 of 53 liquid or air could be retained. The resilient mass (20) biases the core assembly (24) to its extended position.

The external side wall (66) has an external circumferential groove (72). Above the external circumferential groove (72) extends the top end (70) of the side wall (66) of the core assembly (24). Below the external circumferential groove (72) extends the bottom end (74) of the side wall (66) of the core assembly (24). The external circumferential groove (72) of the core assembly (24) provides a mechanical engagement with the resilient mass (20) thereby creating additional bonding area.

The biasing force (resilience) of the resilient mass (20) and the mechanical lock between the resilient mass (20) and the external circumferential groove (72) of the core assembly (24) prevent a permanent displacement of the core assembly (24) from the extended position under the forces applied by a snowplow blade or a vehicle wheel. Once a snowplow blade or wheel passes the pavement marker (10), the core assembly (24), as the result of biasing action (resilience) of the resilient mass (20) and the mechanical lock between the resilient mass (20) and the external circumferential groove (72) of the core assembly (24), returns back to the original extended position at which the bevelled ramps (128) and (130) of the plate (26) are above the level of the surface (14) of the pavement (12). The resilient mass (20) is compressed and expanded with the cycling of the core assembly (24) of the pavement marker (10), and therefore the resilient mass (20) continuously fills virtually the entire space between the external wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16) during this cycle.
Page 35 of 53 The resilient mass (20) prevents liquid from being retained in the space between the external wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16) by substantially filling the entire space between the external wall (66) and the wall (18).

The circumference of the external bottom end portion (74) of the external wall (66) of the core assembly (24) comprises a plurality of equally spaced arcuate grooves (80) and fins (78) (FIG. 35). Fins (78) alternate with the grooves (80). The grooves (80) and the fins (78) provide a mechanical engagement with the resilient ] 0 mass (20) disposed between the external wall (66) of the core assembly (24) and the wall (18) of the pavement cavity (16). The grooves (80) and the fins (78) create additional bonding area with the resilient mass (20) and increase latitudinal, longitudinal and torsional rigidity of the core assembly (24) under the forces created by the snowplow blade or vehicle wheel and function to limit rotation of the core assembly (24) under these forces in the pavement cavity (16). As shown in FIG. 35, a helical spring (254) functions either as an alternative to the resilient mass (20), or in combination with the resilient mass (20).

In alternative embodiments of the invention shown on the FIGS. 36 and 37, the 20 pavement marker (10) is void of the light assembly (30), and instead has a light retro-reflective element (250). The retro reflective element has at least one light reflective surface (252) that returns light toward the source of oncoming light that is preferably emitted from the headlights of an oncoming vehicle. The light retro-Page 36 of 53 reflective element (250) is disposed at the top of the core assembly (24). As shown in FIGS. 36 - 37, a helical spring (254) functions either as an alternative to the resilient mass (20), or in combination with the resilient mass (20).

Operation In the preferred embodiment, the core assembly (24) extends above the surface (14) of the pavement (12) so that the light emitted by the light emitting diodes (236), (240) and (244) can be seen. When a snowplow or vehicle wheel strikes the plate (26) of the core assembly (24), the core assembly (24) depresses from the extended position above the surface (14) of the pavement (12) in to the depressed position inside the housing (22). The resilient mass (20) absorbs the forces encountered during depression of the core assembly (24) to reduce fatigue damage. The resilient mass (20) prevents a permanent displacement of the core assembly (24) from the extended position under the forces applied by the snowplow blade or wheel or vehicle. Once the snowplow blade or vehicle wheel passes the pavement marker (10), the core assembly (24), as the result of biasing action of the resilient mass (20), returns back to the original extended position above the surface (14) of the pavement so that the light emitted by the light emitting diodes (236), (240) and (244) can be seen. In the second aspect of the invention, where the core is mounted within a housing (22), the operation is analogous except that both the core assembly (24) and the housing (22) are movable between the extended position and the depressed position.

Page 37 of 53 The various features of novelty which characterize the invention are pointed out with more particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its use, reference should be made to the accompanying drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention. This invention can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, rather, applicant provides these embodiments so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

While the present invention has been described in terms of a roadway lane separation pavement marker, one skilled in the art will realize that the structure and techniques of the present invention may be applied to many similar structures.
The present invention can be applied in any situation where limited solar energy is needed to be stored to operate a device at night and then automatically cease operation at dawn and recharge. The invention is especially useful where duty cycle can be varied to take account of variations in expected solar energy input, and where an electrical device can be expected to cycle infinitely without significant failure.

Page 38 of 53 Although the invention has been disclosed with regard to particular and preferred embodiment, this is advanced for illustrative purposes only and is not intended to limit the scope of this invention.

Page 39 of 53

Claims

WHAT IS CLAIMED IS

1 A pavement marker comprising:

a core mounted within a cavity formed within a pavement, the cavity having a bottom and side walls, the core comprising side walls and an upper end, the side walls of the core and the side walls of the cavity defining a generally annular space allowing for a lateral and vertical movement of the core within the cavity, a lighting assembly affixed at the upper end of the core, a resilient, compressible and liquid-impervious mass disposed in the annular space to prevent ingress of liquids and solids between the core and the cavity, and a spring means associated with the core and with the cavity, the spring means operative between an extended position in which the lighting assembly protrudes above the level of the pavement, and a depressed position in which the core with the lighting assembly retracts into the cavity below the level of the pavement.

2. The marker according to claim 1, further comprising engaging means formed on the side walls of the core facing the cavity, for engaging the mass with the core.

Page 40 of 53

3. The marker according to claim 2, wherein the engaging means comprises at least one circumferential groove.

4. The marker according to claim 1, wherein the resilient, compressible, liquid-impervious mass is disposed in an entire space between the core and the cavity, the mass operative as the spring means.

5. The marker according to claim 1, wherein the spring means is a helical spring.

6. The marker according to claim 1, wherein the core comprises retaining means formed on the side walls facing the cavity, for restricting rotation of the core relative to the cavity.

7. The marker according to claim 6, wherein the retaining means are selected from vertical grooves, slots, ribs, fins and splines.

8. The marker according to claim 1, wherein the lighting assembly is a self-illuminating light assembly.

9. The marker according to claim 1, wherein the lighting assembly is a light reflecting unit.

Page 41 of 53

10. The marker in accordance with claim 1, wherein the upper end of the core comprises a plate with at least one inclined ramp surface, the plate operative to deflect the core downwardly into the cavity in response to a force applied to the plate.

11. A pavement marker comprising:

a housing adapted to be mounted within a cavity formed within a pavement, the cavity having a bottom and side walls, said housing having side walls and an open top end, the housing dimensioned to be fully retractable into the cavity, the side walls of the housing and the side walls of the cavity defining a first generally annular space allowing for a lateral and vertical movement of the housing within the cavity;

a core mounted within the housing, the core comprising side walls and an upper end, the side walls of the core and the side walls of the housing defining a second generally annular space allowing for a lateral and vertical movement of the core within the housing;

a lighting assembly affixed at the upper end of the core;

a first resilient, compressible and liquid-impervious mass disposed in the first annular space to prevent ingress of liquid between the housing and the cavity;

a second resilient, compressible and liquid-impervious mass disposed in the second annular space to prevent ingress of liquid between the core and the housing; and a spring means disposed in the cavity under the core, the spring means operable between an extended position in which the lighting assembly protrudes above the level of the pavement, and a depressed position in which the core with the lighting assembly retracts into the cavity below the level of the pavement.

12. The marker according to claim 11, wherein the first mass is disposed in an entire space between the housing and the cavity and is operative as the spring means.

13. The marker according to claim 12, wherein the second mass is disposed in an entire space between the housing and the core and is operative as the spring means.

14 The marker according to claim 11, wherein the spring means is a helical spring.

15. The marker according to claim 11, wherein the lighting assembly is a self-illuminating light assembly.

16. The marker according to claim 11, wherein the lighting assembly is a light reflecting unit.

Page 43 of 53

17. The marker according to claim 11, further comprising first engaging means formed on the side walls of the housing facing the cavity, second engaging means formed on the side walls of the housing facing the core, and third engaging means formed on the side walls of the core facing the housing, for engaging the mass disposed between the housing and the cavity and the mass disposed between the housing and the core respectively.

18. The marker according to claim 17, wherein the engaging means comprise circumferential grooves.

19. The marker according to claim 11, further comprising:

(a) a retaining means formed on the side walls of the housing facing the core and a retaining means formed on the side walls of the core facing the housing, for restricting rotation of the core relative to the housing; and (b) a retaining means formed on the side walls of the housing facing the cavity, for restricting rotation of the housing relative to the cavity.

20. The marker according to claim 19 wherein the retaining means comprise vertical grooves, fins, ribs, slots and splines.

21. The marker according to claim 15 wherein the light assembly comprises a solar cell, photo switch, capacitor, light emitting diodes, and control circuitry.

Page 44 of 53

22. The marker in accordance with claim 11, wherein the upper end of the core comprises a plate with at least one inclined ramp surface, the plate operative to deflect the core downwardly into the housing in response to a force applied to the plate.

23. A pavement marker comprising:

a housing adapted to be mounted within a cavity formed within a pavement, the cavity having a bottom and side walls, said housing having side walls and an open top end, the housing dimensioned to be fully retractable into the cavity, the side walls of the housing and the side walls of the cavity defining a first generally annular space allowing for a lateral and vertical movement of the housing within the cavity;

a core mounted within the housing, the core comprising side walls and an upper end, the side walls of the core and the side walls of the housing defining a second generally annular space allowing for a lateral and vertical movement of the core within the housing;

a self-illuminating lighting assembly affixed at the upper end of the core, a first resilient, compressible and liquid-impervious mass disposed in the entire first annular space to prevent ingress of liquid between the housing and the cavity, the mass operative as a first spring means;

a second resilient, compressible and liquid-impervious mass disposed in the entire second annular space to prevent ingress of liquid between the Page 45 of 53 core and the housing, the mass operative as a second spring means, the first and second spring means operative between an extended position in which the lighting assembly protrudes above the level of the pavement, and a depressed position in which the core with the lighting assembly retracts into the cavity below the level of the pavement;

a first circumferential groove disposed on the side wall of the housing facing the cavity;

a second circumferential groove disposed on the side wall of the housing facing the core; and a third circumferential groove disposed on the side wall of the core facing the housing, the circumferential grooves for engaging the first and second mass respectively.

24. The marker according to claim 23, further comprising (a) a retaining means formed on the side walls of the housing facing the core and a retaining means formed on the side walls of the core facing the housing, for restricting rotation of the core relative to the housing; and (b) a retaining means formed on the side walls of the housing facing the cavity, for restricting rotation of the housing relative to the cavity.

Page 46 of 53

25. The marker according to claim 24, wherein said retaining means are selected from vertical ribs, slots, grooves, fins and splines.

26. The marker in accordance with claim 23, wherein the lighting assembly is disposed in a sealed chamber formed in the upper end of the core.

27. The marker in accordance with claim 23, wherein the upper end of the core comprises a plate with at least one inclined ramp surface, the plate operative to deflect the core downwardly into the housing in response to a force applied to the plate.

28. A depressible pavement marker, comprising:

a housing having an upper end portion and a lower end portion, the housing having an external side wall and an internal side wall defining a container open at the top thereof, the housing being flexibly attached to the walls of a cavity formed in a pavement and movable within the cavity between a main position in which the upper end portion of the housing is at or below surface of the pavement, and a displaced position in which the housing is displaced downwardly into the cavity and the upper end portion of the housing is below the pavement surface, whereby vehicles may move across the housing without damaging it;

a resilient, compressible, substantially liquid-impervious mass filling all remaining space within the cavity, the resilient mass biasing the housing upwardly from the cavity to the main position;

a circumferential groove disposed on the external sidewall of the housing, the external circumferential groove engaged by the resilient mass, the external circumferential groove and the resilient mass operative to facilitate reciprocal movability of the housing within the cavity of the pavement, the circumferential groove and the resilient mass operative to limit reciprocal movement of the housing;

a plurality of arcuate grooves and fins disposed on the external side wall of the housing, the arcuate grooves and fins operative, with the resilient mass, to restrict relative rotation of the housing within the cavity in response to forces applied to the housing;

a core assembly having a top end portion and a bottom end portion, the core assembly having an external sidewall and an internal sidewall defining a chamber open at the top thereof, the core assembly reciprocally movable within the container of the housing between an extended position in which parts of the top end portion of the core assembly generally extend above the upper end portion of the housing and above the pavement surface, and a depressed position in which parts of the top end portion of the core assembly are depressed downwardly into the container of the housing and the parts of the top end portion of the core assembly are at or below the Page 48 of 53 upper end portion of the housing and at or below the pavement surface;

a resilient, compressible, liquid-impervious mass filling substantially all remaining space within the container of the housing and biasing the core assembly upwardly from the container to the extended position;

a plate associated with the top end portion of the core assembly, the plate having at least one inclined ramp surface for protecting the outwardly projecting portion of the core assembly and for deflecting the core assembly downward in response to a force applied to the ramp surface;

an internal circumferential groove disposed on the internal sidewall of the housing, an external circumferential groove disposed on the external sidewall of the core assembly, the internal circumferential groove of the housing and the external circumferential groove of the core assembly engaged by the resilient mass disposed between the housing and the core assembly, and wherein the internal circumferential groove of the housing, the external circumferential groove of the core assembly and the resilient mass operative to facilitate reciprocal movability of the core assembly within the container of the housing and to limit outward movement of the core assembly;

a plurality of arcuate ribs and a plurality of slots disposed on the internal sidewall of the housing, a plurality of arcuate grooves and a plurality Page 49 of 53 of fins formed on the external sidewall of the core assembly, the plurality of arcuate ribs of the housing and the plurality of arcuate grooves of the core assembly slidably engaging each other, the plurality of fins of the core assembly and the plurality of slots of the housing also slidably engaging each other, the slidable engagement of the arcuate ribs and the arcuate grooves and the slidable engagement of the fins and the slots restricting relative rotation of the core assembly within the container of the housing in response to forces applied to the core assembly;

a transparent protective member disposed above the chamber of the core assembly, the protective member comprising:

(a) a top surface through which light energy may pass to the chamber of the core assembly;

(b) a bottom surface through which light energy may pass to the chamber of the core assembly;

(c) a plurality of protuberances disposed on the top surface of the transparent protective member to resist abrasive wear resulting from foreign objects moving across the top surface;
and (d) a transparent window generally sloping from the top surface toward the bottom surface of the transparent protective member and through which a visible light could be transmitted;

Page 50 of 53 a light assembly comprising:

(a) a light assembly casing having a top surface and a bottom surface, the light assembly casing disposed within the chamber of the core assembly;

(b) a light assembly pad attached to the bottom surface of the light assembly casing to support and align the light assembly within the chamber of the core assembly;

(c) at least one light emitting diode mounted on the light assembly casing adjacent to the transparent window of the transparent protective member;

(d) a sleeve surrounding the at least one light emitting diode to orient the diode with respect to the transparent window;

(e) at least one solar cell disposed on the top surface of the light assembly casing adjacent to the bottom surface of the transparent protective member to receive light energy and to produce electrical current and voltage;

(f) at least one storage capacitor electrically connected to the at least one solar cell to be charged by the at least one solar cell when the at least one solar cell receives light energy;

(g) a timer circuit having an input and output connected to the at least one light emitting diode to sequentially control a first time period during which the at least one light emitting diode is illuminated and a second time period during which the at least one light emitting diode is not illuminated; and (h) a photo switch connected between the at least one storage capacitor and the timer circuit to energize the timing circuit during conditions of ambient darkness and to deenergize the timing circuit during daylight conditions.

Page 52 of 53