Patent Application
20130340675
The disclosure concerns an apparatus in the form of an applicator to deposit a viscous, flowable mass to a surface, such as roadways, parking areas, air port runways and the like. The disclosure also concerns a traffic printer comprising a number of such applicators and a method of cleaning the valves and their openings.
\Norwegian patent No. 311733 (Trysil Maskin) teaches an apparatus intended for suspension to a vehicle for which a pressurized viscous mass container is supplied with viscous mass from a storage container. The mass is discharges thorough a member arranged to be opened and closed by a flapper and having a discharge slot facing the surface below, the axis thereof being perpendicular to the direction of movement. The member arranged to be opened and closed is connected to a secondary valve member which is arranged with an axis parallel to the discharge slot in a cylindrical sleeve shaped element. The secondary valve member is provided with a longitudinally extending groove in the periphery which can connect an inlet slot from the mass container with the discharge slot at the flapper.
This apparatus works satisfactory for traditional application of longitudinal stripes on road surfaces but is not designed for application of patterns and neither for controlled application of marker coatings with improved reflection function for wet marking and for masses which needs heating.
Norwegian patent No. 316 123 (Trysil Maskin) describes an apparatus for suspension to or integration with a vehicle, comprising a pressurized mass container for a liquid, flowable mass from a storage container, said mass being discharged through a valve member having a row of close adjacently arranged flapper elements that can be activated individually. Even tough this design allows application of simple patterns, it does not allow application of more complicated patterns or symbols.
Another disadvantage of the prior art equipment is that the flapper openings tends to get clogged and that no satisfactory measures have been found to remedy that.
From Norwegian patent No. 325 827 is known an apparatus for suspension to or integration with a vehicle for depositing a flowable substance that can form continuous or divided marker coatings on road surfaces, parking areas and the like, comprising a container for the flowable substance, the substance being discharged through a valve member having a number of computer controlled, close adjacently arranged valve elements that can be activated individually by means of a row of activating members having connecting elements to the individual valve elements. This apparatus, however, no more than the other, provides a solution as how to deposit complex patterns, signs or symbols to a surface.
Advanced signs, symbols and writing on road surfaces must still be applied manually by personnel which for that purpose normally must work on a closed part of a partly open road, with the risk for accidents involved in being so close to traffic. It would have been a very significant advantage both in terms of safety and economy if many of the tasks today being made manually by personnel working very close to motorized traffic could be performed more automatically and by personnel mainly working inside a vehicle. There is thus a need for an apparatus which is able to “write” any desired signs and symbols to a surface such as a roadway.
Below the invention is described in further detail with reference to the accompanying drawings, in which:
With reference to the drawings wherein like numerals represent like parts throughout the Figures, an applicator, a traffic printer and a method of cleaning valves thereof are disclosed.
By “viscous mass” as used herein is understood any mass which are flowable at a convenient elevated temperature and which has a viscosity which prevents it from flowing significantly when applied to a surface typically at ambient temperature, such as temperatures in the range from 5° C. to 40° C. Higher or lower temperature may occur exceptionally. Typical masses are resin based but can contain fragments/particles of other materials, e.g. to increase friction or to improve light reflection from a completed, set mass on a surface.
With “surface” as used herein is understood typically a roadway, a parking space, an airport or other areas having paved surface, such as covered by asphalt or concrete, especially surfaces intended for vehicles.
While the complete “traffic printer” according to the present disclosure below is described as a unit assembled from a number of applicators having a common source of the viscous mass, exemplified as comprising five applicators arranged in two rows, more or fewer applicators than those described and illustrated are possible. It is furthermore an option to produce applicators having valves so close to those side walls of the applicators which are parallel to the direction of movement, that the need for applicators in more than one row is eliminated. In the same manner with which a printer for a computer comprises a complete product even though it requires connection to a computer and use of appropriate software (drivers) to function, the present traffic printer according to the present invention is an independent product even though it requires connection to a computer and accompanying software to function in an optimal manner.
The applicator 11 has in a known manner channels arranged to circulate hot oil to ensure an even and controllable viscosity of the mass to be deposited and to prevent it from setting in the applicator or its openings and valves.
The valve 14 as such comprises an outer valve sleeve 15 which has at least one through opening 16 forming a flow passage from the outside to the inside of the valve sleeve 15. The inner surface of the valve sleeve is smooth and precisely adapted to the outer surface of a valve plug 17 which is slidably arranged in the valve sleeve 15, attached to the valve stem 19 and movable upwards and downwards within limits determined by the valve sleeve, by means of valve plunger 18 attached to the upper end of the valve stem 19 or separably from the latter. The valve sleeve 15 typically has an inner cylinder surface but can also have en inner surface of another shape. In terms of manufacture cylindrical shape is typically the simplest shape and in such a case the valve plug 17 has similar cylindrical piston shape. The valve stem 19 is preferably split in a joint 23 which is adapted to accommodate for tolerance variations with regard to the positioning of the holes 20 in the applicator top cover 21 in relation to the openings 12 in the applicator bottom wall 13. The valve sleeve 15 is adapted to be sealingly and tightly attached in the lower opening 12, preferably by threaded connection.
Each valve stem 19 is attached to a valve lifter 18 which can reciprocate the valve stem 19 up and down respectively by a power impulse which may be hydraulic, pneumatic or in the form of an electromechanically controlled impulse.
According to a preferred embodiment the applicator has two rows of openings 12, provided with valves 14, extending across the width of the applicator. According to a further embodiment the applicator has at least three rows of openings 12 and valves 14 respectively. A person skilled in the art readily understands that the higher the number of rows of valves, the denser the pixels may be arranged so that finer details can be achieved in the printout, provided the valve size is reduced in a manner corresponding to the increase in number.
It is preferred to have at least five openings 12 and valves 14 respectively in each row, more preferred at least eight and most preferred at least ten.
To ensure flexibility of the system, the power generating unit transmitting power impulses must be arranged to be controlled by a computer processor which can have any outer shape, for instance being a portable PC.
In the practice use of traffic printer 37, the controlling of the opening and closing of valves of each applicator is performed a computer program to which the user inputs information of the signs or symbols to be printed. “Printing” on a road or like surface by the traffic printer via moving vehicle is mimicked on a smaller scale by printing on a piece of paper moving past a printer head. In the same manner that the printing software controls flow of ink to printer nozzles over the paper, with dependence on the speed with which the paper moves past the printer head the speed at which the valves are opened and closed must be controlled in dependence on the velocity with which the vehicle with the traffic printer according to the present invention moves. It is not certain that the velocity will be constant in the “printout period” and the computer system therefore uses real time information of the actual speed or other movement or positioning. The mechanism for systems for controlling speed, movement and positioning is not described in further detail.
A particular feature that the controlling software must account for, in a case as shown in
Correspondingly the software can account for mutual delay between valves arranged in different rows across the direction of movement between valves in different rows within one and the same applicator, when the applicators 11 have two (as shown) or more rows of valves 14.
It should be emphasized that the controlling of the applicator valves can be obtained in many different ways and is as such not limiting. The controlling software can be implemented in many different ways. A preferred variant involves use of bitmap files in which the desired signs, symbols and patterns are coded in, divided in pixels. In addition a printer driver translating such bitmap files to instructions that can be interpreted by the traffic printer is needed, hereunder included the particular delays related to different positions in the direction of movement. The encoding of the software is not described in detail.
As shown and described, the valves for opening and closing is packer-free and thereby have a more consistent behavior than prior art valves while exhibiting lower friction, thereby allowing rapid opening and closing without use of conventional hydraulic equipment for controlling and closing. Use of valves being equipped with packers would imply larger degree of friction variation from valve to valve and over time, so that the different valves would show a different response on a controlling signal. This would lead to a less even result with respect to mass applied. Valves having a low friction during opening and closing also can be controlled with less force, such as e.g. use of rapid air cylinders or small electric actuators rather than slower, but stronger, oil based hydraulic cylinders.
Good results over a long period of time often depend upon maintaining clean equipment, especially ensuring that the area around the valve openings 12 does not become clogged by more or less set mass remaining from earlier applications. It is thus important to have reliable procedures for cleaning the valves. For existing, simpler applicators the cleaning has been done manually or immediately before use discharging fresh, hot mass that dissolves and tear away any set mass from earlier applications. The drawback is that these procedures contaminate the equipment and require loss of mass.
With reference to
| Number | Date | Country | Kind |
|---|---|---|---|
| 20110379 | Mar 2011 | NO | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/NO2012/050038 | 3/9/2012 | WO | 00 | 9/9/2013 |
