Amerace Corporation

Stimsonite Corporation

Avery Dennison Corporation

Other

Schwinn Bicycle Company

Sidney A Heenan

Robert M Flanagan

Dennis I Couzin

Liviu A Coman

Richard M Steere

Glenn W Johnson, Jr

Anthony J Montalbano

Henry R Krepel

Robert M Pricone

Michael R Lavender

Frank P Brilando

Jay S Waxman

Rudolph L Schwinn

Loren M Lundtveit

Anthony A Montalbano

Ramon J Ascencio

A method for tooling a pattern of retroreflective microcubes, which pattern can be subdivided into smaller increments within which there are straight line tooling paths, none of which pass through an otherwise solid part of the incremental pattern. The tooling paths within the various increments need not be parallel to a common plane. Various adaptions of the method enable the tooling of a number of specific microcube shapes and for modifying such optical properties of the microcubes as entrance angularity, incidence angularity, orientation angularity, observation angularity, percent active aperture and retroreflectance. Specific techniques govern the pre-selection of cube parameters such as cube axis cant, cube apex decentration, and cube boundary proportions, which parameters can be adjusted independently of each other. Designs tooled by the method can have 100% active aperture at near zero degrees entrance angle. The method involves providing a plurality of plates of micro thickness, each plate having at least one end comprised of a material that can be tooled with polished surfaces by means of an appropriate tool, tooling on said end of each plate an increment of the pattern, and assembling the plates together in various ways to form a master. Retroreflective articles made by means of this technique are expected to provide superior performance when used in pavement markers, highway signs and other applications.

Retroreflective articles having microcubes, and tools and methods for forming microcubes

A roadway marker comprises a solid body member having a lower generally planar surface configured to be adhered directly to a roadway surface. The marker is injection molded as a one-piece structure from a closed-cell foam thermoplastic material using a chemical blowing agent. The bottom surface of the body member may be formed with slight recesses or protrusions such that the entire bottom of the marker fills with adhesive when the marker is installed. Thus, maximum adhesive surface area is provided between the marker and the roadway surface. Further, the closed-cell foam construction creates a marker body which is strong, economical to mold and which does not shrink after molding.

Roadway marker

Retroreflective articles having microcubes, and tools and methods for

A low-profile housing and lens assembly system for use in a pavement marker. The housing is generally shell like and has a recess for accommodating a retroreflective lens element. The housing is provided with means defining a flat base for providing improved adhesion of the marker to the pavement.

Pavement marker

A low-profile snowplowable pavement marker is disclosed including a base member and a retroreflector. The base member has two arcuate-bottom keel members interconnected by a support member. The upper surfaces of the keel members define inclined ramps. The spacing of inner surfaces of the ramps allows retroreflectance of oncoming light while accommodating larger plow blade angles encountered in higher speed plowing. The support member has a central planar support surface for carrying the retroreflector and upwardly facing curved top surfaces providing relief in the base member between the ramps and in front of the retroreflector to allow tires of approaching vehicles to wipe the lens assembly. The housing of the retroreflector is molded from long-glass-fiber-reinforced composite thermoplastic material with a recess for accommodating a retroreflective lens element of a different thermoplastic material.

Snowplowable pavement marker using different materials

A depressible roadway marker has an outer metal housing within which an elastomeric core is held. The core holds a retroreflective lens element above the level of the roadway which depresses into the metal housing when run over by a vehicle tire. The core includes a wiping element to scrub the lens element each time the core is depressed. The core includes structure to absorb the forces encountered during depression to reduce fatigue damage to the core.

Depressible roadway marker

A self-righting roadway marker support for a flexible boundary or roadway marker has a hollow anchor sleeve sunk into a supporting surface, a mounting collar secured to said anchor sleeve, a pivot strut extending through and upward from the collar, a compressible coil spring to resiliently urge the strut into contact with the collar, and a spring stop which selectively limits the extent to which the coil spring may be compressed. An oblong, radiused or chamfered aperture formed in the collar cooperates with a spring-mounting eyebolt to prevent the strut from rotating when deflected. A tool is also disclosed for installing the marker support. The force required to deflect the support assembly is set to be less than the force that would destroy or permanently set or deform the boundary marker.

Self-righting highway marker support and method for installing same

A thin transparent glass sheet is bonded to the substantially flat planar front face of a cube-corner-type retrodirective reflector formed of a light-transmitting synthetic organic resin for covering at least the reflex reflective area thereof. A liquid urethane resin radiation curable to a transparent solid state is applied to the front face of the reflector and one side of the glass sheet is coated with a silane solution which is allowed to dry, and which side is then placed against the urethane resin on the reflector front face and pressed thereagainst until all air bubbles have been forced from the urethane resin and it has spread to a layer of predetermined thickness. The resulting laminate is preheated to a temperature approximating the maximum temperature expected to be experienced in use and then, while at the elevated temperature, the urethane resin layer is radiation cured, for bonding the glass sheet and the reflector together, curing at this temperature causing the adhesive to set so that the glass will be under compression when the laminate is exposed to the working temperature range, and the laminate is then maintained at about 150.degree. for 30 to 60 minutes to enhance the chemical bonding of the silane to the glass and the adhesive.

Method for making an abrasion-resistant reflective marker

A mobile apparatus for detecting reflectivity of markers on a roadway surface is disclosed. The apparatus includes a vehicle and an elongated shroud assembly which has mounted therein a light source for directing light toward a marker and a light receptor for detecting light reflected from the marker, as the apparatus moves along the roadway surface. An aperture housing is mounted to the shroud and light directed to and reflected from the marker must pass through the aperture housing. In one embodiment the shroud is pivotally connected at one end to the vehicle and positioning means are provided for maintaining that portion of the shroud which will normally overlie the marker when light is reflected therefrom at a uniform and preselected height from the roadway surface. In another embodiment, the shroud is rigidly fixed to the vehicle, but the aperture is constructed to 'float' at a uniform and preselected height from the roadway surface. By so uniformly positioning the aperture housing or a point on the shroud, the length of the light path from the source to the marker and back to the receptor is maintained substantially constant, regardless of vertical movement of the light source relative to the roadway surface due to bouncing, irregular road surfaces, etc.

Mobile testing apparatus

Disclosed herein are a method and apparatus for continuously embossing a repeating pattern of precise detail, in particular, cube-corner type reflector elements, on one surface of a sheet of transparent thermoplastic material to form retroreflective sheeting. A continuous embossing tool in the form of a flexible thin metal belt or cylinder has on its outer surface an embossing pattern which is the reverse of the pattern to be formed. The embossing tool is continuously moved at a predetermined speed along a closed course through a heating station where the temperature of a portion of the embossing tool is raised to be above the glass transition temperature of the sheeting and a cooling station where the heated portion of the embossing tool is cooled to be below that glass transition temperature. The sheeting is continuously moved at the predetermined speed from a supply thereof into engagement with the embossing pattern on the tool and is pressed thereagainst continuously at a plurality of pressure points sequentially spaced along the heating station, with the one surface of the sheeting confronting and engaging the embossing pattern until the sheeting is raised above its glass transition temperature and conforms to the embossing pattern on one face. The sheeting is maintained in engagement with the tool until the tool passes the cooling station and the sheeting is lowered below its glass transition temperature and the pattern solidifies. The sheeting is thereafter stripped from the tool.

Method and apparatus for embossing a precision optical pattern in a

Disclosed herein is a pavement marker for engagement with an underlying roadway for providing a marking visible from an oncoming vehicle on the roadway surface. The pavement marker comprises a lens member of light-transmitting synethetic resin including a front face having a light-receiving and refracting portion adapted to be inclined at an angle of at least 15.degree. and a rear face having reflex reflective means for reflecting light transmitted through the light-receiving and refracting portion back to the source. The pavement marker has an untempered glass sheet fixedly disposed on the light-receiving and refracting portion and the glass is in compression throughout the expected temperature range to which the pavement marker is exposed in use.

Growing community of inventors

Park Ridge, IL, United States of America

Sidney A Heenan