US 3836275 A
A roadway marker system for improved wet-night visibility where snow plowing is prevalent in which a preformed strip is provided with recesses into which inserts can be placed, the inserts being provided with reflector elements, electrically activated light emitting devices, electrical heating elements, electrically activated infra-red radiation emitting devices, or radioactive light emitting elements. Electrical conductors are also embedded in the strip to supply power to the inserts.
Description (OCR text may contain errors)
iJnited States Fatent 11 1 Finch Sept. 17, 1974 ROADWAY MARKER DEVICE  Inventor: Dan Milton Finch, 200 Arlington Ave., Kensington, Calif. 94707  Filed: Mar. 31, 11972 21 Appl. No.: 240,155
 10.8. C1. 404/113  llnt. Cl E011t 9/06  Field 01 Search 404/9, 10, II, 12, 13,
 References Cited UNITED STATES PATENTS 462,480 11/1891 Finley 52/586 X 1,885,941 11/1932 O'Brien 404/12 1,948,335 2/1934 Clough 2,225,496 12/1940 Gethin et 211,. 3,485,148 12/1969 Heenan 3,535,204 10/1970 Truxa 52/586 X 3,693,511 9/1972 Medynski 404/10 FOREIGN PATENTS OR APPLICATIONS 405,471 2/1934 Great Britain 404/9 483,342 4/1938 Great Britain 404/9 Primary Examiner-Ramon S. Britts Assistant Examiner-Thomas J. l-liolko Attorney, Agent, or Firm--Robert R. Tipton [5 7] ABSTRACT A roadway marker system for improved wet-night visibility where snow'plowing is prevalent in which a preformed strip is provided with recesses into which inserts can be placed, the inserts being provided with reflector elements, electrically activated light emitting devices, electrical heating elements, electrically activated infra-red radiation emitting devices, or radioactive light emitting elements. Electrical conductors are also embedded in the strip to supply power to the inserts.
2 Claims, 10 Drawing Figures BACKGROUND OF THE INVENTION This invention relates to marking devices and in particular, to devices for marking roadways and paved areas.
The present method of marking roadways and other paved areas includes either applying a painted line directly on the pavement in which flne glass beads are mixed with the paint, the glass beads acting as reflector elements, or, applying an adhesive material to the pavement and affixing thereto individual cap-like reflector elements, or, embedding in the pavement individual lighting units.
The painted strip with intermixed glass beads has proved to be the poorest means for providing a luminous marker strip under wet-night conditions because the water and snow blocks out the light and prevents the glass beads from performing their reflecting function.
The cap-like reflectors offer somewhat better visibility since they project above the pavement surface and protrude above the thin layer of snow and water, however, because they do project above the pavement an appreciable amount in order to perform their reflecting function and because they are fastened to the pavement surface with an adhesive, they are easily removed from the pavement by the relatively large shear forces exerted by the action of a snow plow blade scraping at or near the pavement surface.
The embedded lighting units, because of their relatively high initial cost and their high cost of installation, although used extensively for airport runway and taxiway lighting, have not been used extensively in roadways and highways.
SUMMARY OF THE INVENTION The roadway marking system of the present invention comprises a flexible molded strip of resilient material in which are disposed electrical conductors and recesses adapted to receive inserts.
The inserts can include reflector elements, radioactive light emitters, electrically activated light sources, heating elements or infra-red radiation emitters or the electrical conductors may act to heat the entire marker strip.
The inserts are of a low profile and are designed to withstand the shear forces encountered during snow removal.
The electrical conductors may also be used as the means for holding inserts in the recess.
It is, therefore, an object of the present invention to provide a wet-night visible roadway marker system.
It is another object of the present invention to provide a roadway marker device and system in which the marking devices are easily replaceable.
It is another object of the present invention to provide a raodway marker device and system having a low profile.
It is a further object of the present invention to provide a roadway marker device and system in which the marking device is selfdlluminating.
It is another object of the present invention to provide a roadway marker device and system in which the marking devices are heated.
These and other objects of the present invention will be manifest upon study of the following detailed description when taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is an isometric view of a typical marking strip of the present invention with an exploded view of a typical insert.
FIG. 2 is a section through a typical marker strip of the present invention taken at line 2-2 in FIG. ll.
FIG. 3 is an isometric view of a typical reflector insert.
FIG. 4 is a typical parital front elevational view of a typical reflector element.
FIG. 5 is a partial plan view of a typical reflector ele ment.
FIG. 6 is a cross-section of a typical reflector element taken at line 6-6 in FIGS. 4 and 5.
FIG. 7 is an isometric view of a typical selfilluminated insert.
FIG. 8 is an isometric view of a typical heated insert.
FIG. 9 is an isometric view of atypical infra-red radiation emitting insert.
FIG. 10 ia a partial elevational section of a method of securing an insert in the recess of the marking strip.
DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. ll, there is shown an isometric exploded view of the basic roadway marker system of the present invention comprising a flexible strip 10 having disposed longitudinally therein a pair of cylindrical reinforcing wires Ma and llllb which can also be electrically conductive, and means defining a recess 12 into which a typical insert 15 (shown both in exploded view and in place) will fit and be flush with the surface of strip 10 or protruding only enough to function visually and mechanically.
As shown in FIG. 1, strip lltl is installed in a trough 16 in pavement ]l7 and held in place by an adhesive material 18.
FIG. 2, being a cross-sectional elevation of strip lltl taken at lines 22 of FIG. 1, illustrates, in greater detail, the relationship of the various elements.
Wires llla and lllb are disposed on each side of recess 12 so that one longitudinal half of wires lllla and lllb protrudes into recess 12 while the other half is embedded in and held in place by the material of strip 10.
By providing a groove 20, adapted to receive the one half of wire llla and lllb on each side of insert 15, wires Ma and lllb thus act as a means or detent for retaining or holding insert 15 in place in recess 12.
Insert 15 may be arranged in many configurations. For example, insert llSA, FIG. 3, :is a simple reflector unit utilizing a transparent reflex reflector device.
Insert 15B, FIG. 7, includes a self-illuminating light source insert utilizing a small inacandescent or gaseous discharge lamp or solid state light emitting device.
Insert C, FIG. 8, includes a reflex reflector unit and an electrical heating element for melting snow and ice in the immediate area of the insert.
Insert 15D, FIG. 9, includes an infra-red radiation source for use in a system which includes vehicle mounted infrared guidance equipment during low visibility fog conditions.
Both strip and insert are preferably fabricated of a tough but resilient thermoplastic material having self-lubricating properties such as found in the polyamide and tetrafluoroethylene group of thermoplastics.
With reference to FIG. 3, insert 15A comprises a generally rectangular base 23 adapted to fit into recess 12 (FIG. 1) with its top plane 24 generally flush with the top surface of strip 10.
Grooves 25a and 25b are provided on each side of base 23 and are adapted to receive the longitudinal half of wires 11a and 11b, respectively, which protrude into recess 12.
A reflex reflector unit 27 is fixed to base 23 proximate the middle of insert 15A and is arranged to protrude above plane 24, the roadway surface, approximately, but generally not to exceed, one-quarter of an inch.
Under normal snow plowing conditions, the snow plow blade does not rest fully on the pavement surface but is allowed to be about one-quarter inch above the pavement surface to prevent excessive wear of the snow plow blade and also to prevent damage to the roadway surface. However, because the road surface is generally uneven, the blade may come in contact with the pavement at one or more points including the top of strip 10 and insert 15.
For this reason, insert 15A is provided with a plurality of tapered ridge protectors 28 longitudinally disposed on insert 15A to cause a snowplow blade to ride up and over reflector 27.
A typical reflex reflector unit 27 is shown in FIGS. 4, 5 and 6. FIG. 4 shows a front elevational view of reflex reflector unit 27. FIG. 5 shows a plan view of reflector unit 27 and FIG. 6 is a section taken through reflector unit 27 in FIGS. 4 and ,5 taken at line 66.
Reflector unit 27 comprises basically a front refracting lens 29, a back reflecting surface 20 and a lockform base 31 adapted to be molded into base 23 (shown by dashed lines) of insert 15A.
Back reflector is coated with aluminum or other material that will act to provide a reflecting surface.
Both front lens 29 and back reflector 30 are shperical in shape having radii 33 and 34, respectively.
Light rays 36 from a vehicle headlamp (not shown) are shown entering front lens 29 where they are refracted to back reflector 30 which reflects ray 36 back through front lens 29 and back to the driver of the vehicle.
Reflector 27 should be capable of reflecting light received at angles of from 05 above base strip 10 and O30 from the longitudinal axis of base strip 10 back within the same angular range. Such reflectors can include the corner-cube type of reflector as well as the type illustrated.
With reference to FIG. 7, light source insert 158 is shown in isometric and partial cut-away view and comprises a base 40 in which is embedded an incandescent light source 41 having a glass envelope 42, a filament 43 which is connected to electrodes 44a and 44b.
Light source 41 can be any type of light source other than incandescent such as a gaseous discharge type, solid state or semi-conductor type or be a radioactive energized type, the last type would not, of course, require an outside source of power from conductors 11a and 11b.
Base 40 is also provided with grooves 46a and 46b along its sides which are adapted to receive the exposed longitudinal half of wires 11a and 11b, respectively, in recess 12 (FIG. 1).
Also disposed along the sides of base 40 with grooves 46aand 46b are electrodes 48a and 48b which are formed to be flush with the sides of base 40 and match grooves 46a and 46b, respectively.
Electrodes 48a and 48b are electrically connected to electrodes 44a and 44b, respectively, by means of conductors 49a and 49b, respectively. Thus when insert 158 is placed in recess 12 (FIG. 1) electrodes 48a and 48b are in contact, respectively, with wires 11a and 11b permitting an electrical current to flow through conductors 49a and 49b through light source 41.
The material of base 40 may, therefore, be fabricated from a transparent material to afford minimum absorption of light from source 41. So that insert 15B will be visible at small angles, 0l0, above the pavement, its surface could be etched or provided with a surface of a light diffusing material.
For the embodiment illustrated in FIG. 7, the top of base 40 comprises a pair of tapered ridges 45 at each side of base 40 which serve to protect cylindrical refracting lens 47 from snow plow blade damage. Lens 47 can be of several configurations to either direct the light from source 41 in one direction or both directions as shown.
For the configuration shown, filament 43 can be at or above the top surface of base 40 for better visibility. The curvature of lens 47 can be varied to focus the light toward the oncoming vehicle for better utilization of emitted light.
With reference to FIG. 8, heated reflector insert 15C is shown in isometric and partial cut-away view and comprises a base 50 on which is mounted a reflex reflector 51 having internal reflecting surfaces 52 and electrical heating element 54 which is connected to electrodes 56a and 56b.
Although reflector 51 is shown with flat reflecting surfaces, the corner-cube type of reflector common in the art may also be used.
It will be noted, similar to insert 158, that base 50 is also provided with grooves 57a and 57b along its sides which are adapted to receive the exposed longitudinal half of wires 11a and 11b, respectively, in recess 12 (FIG. 1).
It will also be noted, similar to insert 15B, that electrodes 56a and 56b are formed to be flush with the sides of base 50 of insert 15C and match grooves 57a and 57b, respectively.
Thus, when insert 15C is placed in recess 12 (FIG. 1) electrodes 56a and 56b are in contact, respectively, with wires 11a and 11b permitting an electrical current to flow through heating element 54 to melt any ice or snow which might be covering reflector 51.
It will be noted further that reflector 51 is formed to achieve a low profile having its front and rear surfaces ramped so that front and rear edges are level with the surface of strip 10 when insert 15C is installed in recess 12, so that the horizontal shear forces from the action of a snow plow blade are'minimized.
With reference to FIG. 9, infra-red radiation source insert ISD is shown in isometric and partial cut-away view and comprises a base.60 on which is mounted infra-red radiation source 61.
Infra-red radiation source 61 comprises a radiating surface 62 and heating elements 63 in thermal contact with surface 62.
Insert 15D, similar to inserts 15B and 15C, also comprises grooves 64a and 64b along the sides of base 60 which are adapted to receive the exposed longitudinal half of wires 11a and 11b, respectively, in recess 12 (FIG. 1).
It will also be noted, similar to inserts 15B and 15C, that electrodes 66a and 66b are formed to be flush with the sides of base 60 and formed to match grooves 64a and 64b, respectively. Electrodes 66a and 66b are connected, respectively, to each end of heating element 63.
Thus, when insert ISD is place in recess 12 (FIG. 1), electrodes 66a and 66b are in contact, respectively, with wires 11a and 11b, permitting an electrical current to flow through heating element 63 raising the temperature of radiating surface 62 to a level desired for use as an infra-red radiation source.
As shown in FIG. 9, source 61 is slightly raised or ramped for better visibility, however, it may remain flat and flush with the surface of strip 10.
With reference to FIG. 10, there is shown a partial elevational section through strip and insert in which a ridge 70 is provided in the bottom of recess 12 and a matching groove is provided in the bottom of insert 15 running parallel to wire 11a (wire llllb, not shown).
The sides of ridge 70 make an angle of about 45 with the bottom of recess 12, which angle can be varied as desired, so that the underside of groove is biased against wire 11a and acts to further lock insert 115 into recess 12.
Strip 10 is installed in a roadway by first cutting a flat groove 16 in the pavement to a depth slightly less than the thickness of strip 10. In practice this would be about 0.095 inches. The maximum thickness of strip 10 would be about 0.125 inches.
Strip 10 is attached to the bottom of groove 16 with suitable adhesive which is common in the art.
Recesses for inserts will normally be spaced about every 5-7 feet.
For areas not encountering snow removal conditions, strip 10 could be fastened to the roadway without cutting a groove.
As an additional feature, the current flowing in wires 11a and 11b could be adjusted as can the material of the wires so that they can function as heating elements to melt ice and snow from the entire strip, thus permitting all inserts and the strip itself to be free of ice and snow for greater visibility.
1. A roadway marker strip comprising a resilient base strip having a generally planar top surface,
means defining a resilient insert,
means defining a recess in said base strip along the top surface thereof for receiving said insert,
a pair of reinforcing members disposed parallel to each other and longitudinally affixed in said base strip and passing through said! recess, and
means defining a groove in said resilient insert adapted to receive said reinforcing member.
2. A roadway marker strip comprising a resilient base strip,
means defining an insert,
means defining a recess in said base strip for receiving said insert,
- a pair of reinforcing members disposed parallel to each other and longitudinally in said base strip and passing through said recess,
said insert including means defining a groove adapted to engage said reinforcing member, and
means protruding from the bottom of said recess for biasing said groove against said reinforcing mem-