Patent Application
20090208287
Roadways typically have markings painted thereon to delineate lanes for traffic movement, as well as safety zones for passing vehicles. The white or yellow paint is usually applied by a moving truck or similar mobile device using a pressurized system to spray solid or broken lines ranging from 4-8 inches wide onto the road surface. This prior art road striping equipment also normally includes a bead applicator positioned immediately behind the paint spray nozzle or gun which applies a stream of small diameter glass beads or reflective particles onto the paint. The beads stick to the wet paint, and reflect light from vehicle headlights back toward the vehicle during nighttime driving so as to enhance visibility of the painted line. In the traditional paint and bead application process, the paint striper truck moves at 8-12 miles per hour. This forward velocity of the truck produces a forward velocity for the dispensed beads, which tend to roll in the paint, thereby causing the bead to be partially or completely covered with paint, thereby reducing or eliminating the light which is reflected by the beads.
U.S. Pat. No. 6,511,259 attempts to solve the bead rolling problem by discharging the beads in a rearward direction using a fluid assisted dispenser so that the reflective particles are ejected at substantially the same velocity that the striper truck or vehicle is moving forwardly, but in the opposite direction, so that the relative velocity of the beads as they hit the pavement is close to zero. However, the device of the U.S. Pat. No. 6,511,259 patent does not have the ability to adjust the particle dispenser as the speed of the striper vehicle varies. Therefore, the zero relative velocity of the beads can be achieved at only one vehicle speed.
Accordingly, a primary objective of the present invention is the provision of an improved road striping vehicle which dispenses reflective beads into wet road stripe paint at a relative zero velocity, regardless of the vehicle speed.
Another objective of the present invention is the provision of an improved road striping vehicle which applies paint and reflective particles to the road at varying speeds.
Another objective of the present invention is the provision of a road striping vehicle which utilizes a pair of opposing rollers to dispense glass beads into freshly sprayed paint on the road.
A further objective of the present invention is the provision of a road striping vehicle having rollers for dispensing reflective beads into road stripe paint, wherein the speed of the rollers can be adjusted so as to correspond to the speed of the vehicle.
Still another objective of the present invention is an improved method for applying reflective beads to a painted road stripe so as to eliminate or minimize rolling of the beads in the paint.
Yet another objective of the present invention is the method of applying a reflective line onto a road wherein a paint stripe is applied and then reflective beads are dispensed into the wet paint with substantially zero horizontal velocity.
A further objective of the present invention is the provision of an improved road striping vehicle which is economical to manufacture, and which is efficient, effective, accurate and durable in use.
These and other objectives will become apparent from the following description of the invention.
The present invention offsets the forward movement of the paint striping truck by expelling the beads or reflective particles rearwardly and downwardly at substantially the same speed as the vehicle, thereby allowing the bead to have a net velocity of approximately zero. Accordingly, the beads fall onto the paint without rolling forward, thereby maximizing the reflective function of the particles or beads.
In a preferred embodiment, the reflective particles are dispensed onto the paint by a pair of parallel rubber coated rollers. One of the rollers is driven by an electrical motor which receives a variable voltage signal from an electrical control device which constantly measures the ground speed of the truck and adjusts the speed of the drive roller to substantially match the speed of the vehicle. A second roller is driven by the first roller through intermeshing gears or by direct engagement between the roller surfaces. The glass beads or reflective particles are stored in a pressurized vessel on the truck and conveyed under pressure to one or more bead guns via a flexible hose. A metering nozzle dispenses the beads into the intake side of the rotating rollers, with the beads passing through the nip point for downward and rearward discharge onto the wet paint at a controlled velocity preferably equal to the opposite forward velocity of the paint truck. Thus, the particles are dispensed with a net zero velocity relative to the road surface.
a is an enlarged view taken along the circle 1A of
The zero velocity bead dispenser assembly of the present invention is generally designated in the drawings by the reference numeral 10. The assembly 10 is mounted on a road striper vehicle or truck 12, which includes a paint storage tank or vessel 14, and a pressurized tank or vessel 16 for storing reflective particles, such as glass beads. The vehicle 12 also includes one or more paint nozzles 18 for spraying paint onto the road surface, so as to form lines, such as those commonly used to mark the driving lanes on the road, passing and no passing zones, the road shoulders, or other markings.
The bead dispenser assembly 10 includes a bead gun 20, a pair of rollers 22, 24, and a chute 26 extending between the bead gun 20 and the rollers 22, 24. The bead gun 20 is operatively connected to the bead vessel 14 via a hose (not shown). The rollers 22, 24 are rotatably supported between a pair of mounting plates 28 at the opposite ends of the rollers 22, 24.
Preferably, roller 22 is mounted above roller 24, with the rollers 22, 24 being closely spaced so as to define a nip point 30 between the rollers. The chute 26 directs the beads from the bead gun 20 into the nip point 30.
The rollers 22, 24 are rotatably supported by bearings 32. The bead dispenser assembly 10 also includes an electric motor 34 mounted between a pair of brackets 36. The motor includes a drive shaft 38 which is coupled to the roller 22 so as to drive the roller when the motor 34 is operating. The roller 22, in turn, rotates the roller 24 via intermeshing timing gears 38, 40 on the ends of the rollers 22, 24, respectively. As an alternative to the meshing gears 38, 40, the rollers 22, 24 may engage one another, such that the drive roller 22 rotates the idler roller 24.
The orientation of the rollers 22, 24 can be adjusted via an adjustable canting mechanism 42. The canting mechanism 42 allows the angle at which the beads are discharged from the rollers 22, 24 to be varied. Preferably, the lower roller 24 is positioned slightly forwardly of the upper roller 22, such that the beads are discharged in a downward and rearward direction.
The speed of the motor 34 is controlled by an electrical control device 46 which continuously senses or monitors the velocity of the truck 12, and sends a variable voltage signal to the motor 34, so as to automatically adjust the speed of the motor, and thus the rotational speed of the rollers 22, 24, so as to substantially match the velocity of the truck 12. One example of a commercially available control device 46 is sold by Minarik Drives, Model No. DC60-12-24. Preferably, the motor 34 is a 12-24 volt motor.
The assembly 10 includes a protective guard or shield 50 surrounding the rollers 22, 24 and the motor 34, as best seen in
The bead dispenser assembly 10 can be mounted to the truck 12 in any convenient manner. As seen in the drawings, a frame is provided for supporting the assembly 10 behind the paint nozzle(s) 18 of the truck 12. The frame includes a lower mounting bar 54 which extends longitudinally within the shield 50 to support the mounting plates 28 of the rollers 22, 24 and the brackets 36 for the motor 34. The lower mounting bar 54 is secured to an upper mounting bar 56 by rods 58 and brackets 60. Similarly, the bead gun 20 is connected to the lower mounting bar 54 an adjustable bar 62 extending through a bracket 64 on the lower bar 54.
A protective shield or guard 70 is provided on the assembly 10 so as to house the rollers 22, 24 and the motor 34, as seen in
It is understood that the various mounting hardware, such as the bars, rods and brackets, may take configurations and orientations different from that shown in the drawings, without departing from the scope of the present invention.
In use, the paint striping vehicle 12 lays a paint stripe onto the road via the paint nozzle 18. The bead dispenser assembly is located behind the paint nozzle 18 so as to discharge reflective particles, such as glass beads, into the wet paint so as to be partially imbedded in the paint. The rollers 22, 24 discharge the beads from the nip point 30 at a rearward velocity substantially matching the forward velocity of the vehicle 12, such that the beads are laid into the paint with a net zero velocity, thereby precluding or minimizing rolling of the beads in the paint. Thus, the beads maintain maximum reflectiveness. If the speed of the vehicle 12 changes while the paint and reflective beads are being applied to the road surface, the speed controller 46 will automatically adjust the speed of the motor 34, and thereby the rotational speed of the rollers 22, 24, so as to maintain the zero velocity dispensement of the beads relative to the road surface.
The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives.
This application claims priority under 35 U.S.C. §119 of a provisional application Ser. No. 61/028,653 filed Feb. 14, 2008, which application is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61028653 | Feb 2008 | US |
