Patent Publication Number: US-2006013654-A1

Title: Method, apparatus and template band for producing three-dimensional profiled road surfaces

Description:
The invention relates to a method, a device and a template belt or band for making three-dimensional profiled or structured road surfaces, especially from concrete or asphalt.  
      Roads, paths, and surface materials (designated hereinafter as road surfaces) are provided with three-dimensional profiled surfaces for attractive and cost-effective structuring of surfaces of standing or stopped traffic, of inner city regions, of pedestrian paths, and of paths and surfaces in recreational devices, both in outside and inside areas, and so forth. These structured surfaces are also provided for avoiding the danger of slipping, in particular with adverse weather conditions.  
      According to the state of the art, for producing these types of surfaces, a template with the desired surface structure, for example with the reproduction of a paved or natural stone-like surface, is placed by hand on a monolithic surface of a hardenable road surfacing material, such as asphalt or concrete, before hardening or setting. The pattern of the template is impressed into the surface by striking or impressing. By surface-active pigments and other additives, which likewise are applied by hand, the surface of the road surface can be formed to be colored.  
      The reproducibility and the quality of the surface properties achievable with the manual method, however, depend greatly on the qualification and experience of the personnel. In addition, by performing the discontinuous manufacturing method manually, one achieves only a very minimal productivity.  
      Attempts to profile the surfaces of hardenable road surfaces such as concrete and asphalt with hand-pulled, unguided rollers having a surface pattern produced no results. They lead to the formation of beads and thereby, to tearing of the surface structure. In addition, a separate roller diameter was required for each pattern.  
      A method for pressing an asphalt surface with a pattern with the following steps is described in EP 0692046B1:  
      1. Placing a bendable template on the (not yet hardened) asphalt surface,  
      2. Impressing the template into the asphalt surface under pressure,  
      3. Removing the pressure device and lifting up the template, and  
      4. Applying a colored cement coating.  
      With the solution of EP 0692046B1, a discontinuously operating method is proposed, in which no continual production is possible based on the limited length of the flexible template.  
      U.S. Pat. No. 3,998,564 discloses a method for producing splices in roadways made of cast iron or poured concrete with the following steps:  
      1. Positioning a flexible film with a plurality of ribs spaced parallel and a minimal distance from one another on the side facing the track cover,  
      2. Impressing the flexible film into the not yet hardened surface of the concrete,  
      3. Removing the flexible film after hardening of the structured surface of the concrete roadway cover.  
      Also with this method, no continuous production of a profiled surface is possible due to the finite length of the flexible film. 
    
    
      The object of the present invention is to provide a method, a device, and a template for making three-dimensional profiled or structured road surfaces, in particular made of concrete or asphalt, which lead to reproducible results of high quality and increase the productivity of the entire process.  
      This object is solved with a method having the features of claims  29  and  30 , a device with the features of claim  1 , and a template with the features of claim  26 . Advantageous embodiments of the invention are the subject matter of the dependent claims.  
      The mechanized running of the partial process of pressing three-dimensional profiled road surfaces takes place in multiple steps:  
      1. The desired surface pattern is disposed on a template belt formed as an endless belt. The template is impressed onto the not yet hardened surface of a hardenable road surfacing material under pressure into the surface of the road surfacing material.  
      2. In order to avoid warping and, therewith, the formation of tears in the pressed surface of the road surfacing, the template, in the further process sequence, is placed into a form that is level with the road surface.  
      3. After passing through this flat partial region, in which no pressing work is achieved but the shaped pressed pattern is stabilized, the template is lifted slowly and at a very small angle again from the surface of the not yet hardened material.  
      4. After a revolution of the continuous template belt, the described initial area of the belt is again in the position in which the pressing work is performed. The process sequence is repeated.  
      5. At each time point of the process, a partial region of the template is in contact with the not yet hardened surface of the hardenable road surfacing material.  
      The individual process steps therefore run continually and simultaneously.  
      The advantage of this method compared with the known manual methods and the solutions disclosed in the cited patent documents is that structured road surfaces can be made with uniformly higher quality and greater productivity.  
      The device of the present invention for making three-dimensional profiled road surfaces includes a frame ( 1 ), a first and second roller body ( 2 ,  3 ), a tension roller ( 4 ) disposed between the first and second roller bodies, whereby the first and the second roller bodies and the tension roller are disposed on the frame to be axially parallel to one another, and a continuous, flexible template belt ( 5 ), which is arranged to run around the first roller body, the tension roller and the second roller body.  
      In one advantageous form of the invention, the first and second roller bodies and the tension roller are arranged relative to one another such that the template between the first roller body and the tension roller lies always on the surface of the road surfacing material, while the part of the template between the tension roller and the second roller body is raised slowly and steadily at a slight angle from the surface ( 6 ) by means of particular positioning of the second roller body after impressing of the surface pattern into the not yet hardened road surface, so that no road surfacing material is torn out.  
      In a further advantageous embodiment of the invention, the first and second roller bodies have the same diameter, which is selected to be of such a magnitude that the template belt is not exposed to any intense bending, which affects favorably the wear behavior of the belt. In addition, because of the relatively large diameter, upon contact of the template belt on the surface to be pressed and upon impressing of the three-dimensional structure, no or very minimal material displacements can occur. Small roller diameters would lead here to the inevitable destruction of the surface structure.  
      In a further advantageous embodiment of the invention, the first roller body has a vertical adjustment device ( 7 ), which is equipped to lower the roller body for beginning the pressing process defined on the surface of the surface to be pressed, without causing the eventual sinking of the device into the not yet hardened road surface due to the excessive weight of the device. This feature is of particular advantage when the device has an undercarriage according to a further advantageous embodiment.  
      In a further advantageous embodiment of the invention, the vertical adjustment device has a force regulating element ( 8 ), which permits a controlled adjustment of the pressure acting on the first roller body on the surface to be pressed. In this manner, it is permitted that the pressure required for a functional impressing of the surface pattern on the surface of the road surfacing material can be effective, that too intense deformations are avoided, and that manufacturing tolerances can be compensated in the level of the road surface layer.  
      The force regulating element preferably is a spring or a hydraulic cylinder. The advantage of the spring is its minimal price and the freedom of maintenance; the advantage of the hydraulic cylinder is the uncomplicated and fast adjustment of the necessary force. The simplest type of force regulating represents the weight change of the first roller body, which can be achieved in an uncomplicated manner, for example by a water ballast in the roller body.  
      In a further advantageous embodiment of the invention, the first or preferably the second roller body has a horizontal adjustment device for equalizing different template lengths, which are provided based on different surface patterns with different pattern masses.  
      In a further advantageous embodiment of the invention, the frame has an undercarriage, which can be a wheel undercarriage for example. In this case, the wheels can drive on a leveled driving surface, for example on rails, which are placed directly to the right and left near the surface to be processed.  
      In a further advantageous embodiment of the invention, the undercarriage is a caterpillar undercarriage, so that rails are not necessary, since it can, for example, drive on a concrete subgrade.  
      In a further advantageous embodiment of the invention, the device has an edge formwork at least in the area of the template belt lying on the surface of the road surfacing material, whereby this glides laterally and flatly on a fresh concrete body. In this manner, the device can operate on the track and the fresh concrete body remains dimensionally stable.  
      The device of the present invention can be pulled by a drivable construction device, for example a concrete road paver.  
      In a further advantageous embodiment of the invention, the frame has a drive unit, by means of which the device can operate autonomously.  
      The drive unit can be a hydraulic, electric, or combustion engine.  
      In an advantageous embodiment of the invention, the speed of the drive unit is infinitely controllable, so that the speed of the device can be adapted to different work conditions.  
      Preferably, the undercarriage can be driven by the drive unit.  
      Preferably the first roller body is driven directly by the undercarriage.  
      In this manner, the first roller body always runs synchronously to the undercarriage. A further advantage of this power transmission is that by means of the torque transferred onto the first roller body, driving forces, which as known can cause bead formation in the road surfacing material, can be substantially avoided.  
      In a preferred embodiment of the drive unit, a chain drive is used between the undercarriage and the first roller body.  
      In a further preferred embodiment of the device, the power transmission from the first to the second roller body takes place by means of the template belt tensioned by the tension roller. For receiving the tensioning forces and for reducing the wear, the template belt should be provided with a reinforcement in another advantageous embodiment of the invention. It is also possible to effect the power transmission from the first to the second roller body by means of a chain or belt drive or a shaft.  
      If additives and auxiliary materials are to be added to the upper layer of the road surfacing material, for example pigments and separating agents, then it is advantageous to locate the devices on the frame, for example supply devices, mixing devices, dispensing devices, and processing devices for these materials.  
      These supply devices, mixing devices, dispensing devices, and processing devices can be driven by the drive unit in an advantageous embodiment of the invention.  
      In a preferred embodiment of the invention, the supply devices, mixing devices, dispensing devices, and processing devices can be controlled individually and independently from the drive speed of the device.  
      A further subject matter of the invention is the template belt, which is used in the device of the present invention.  
      It was shown that for this purpose, a flexible, continuous template belt is best suited, on which a three-dimensional surface pattern is arranged on one side, which represents the negative of the desired surface pattern of the road surfacing material.  
      Preferably, the template belt includes a reinforced support belt with at least one three-dimensional mold element disposed on a side of the support belt.  
      In a preferred embodiment of the invention, the template belt can be exchangeable. Thus, with one device, different surface patterns can be impressed. For the uncomplicated changing of the belts, the device is equipped such that the dismantling or mounting of the belt can take place from one side.  
      The first roller body can be driven by a drive unit and the belt speed can be synchronized with the working speed via a power transmission element.  
      The second roller body serves for receiving the template belt and for equalizing different belt or pattern lengths. Simultaneously, the higher placed second roller body together with the pressing roller effects the gradual vertical lifting of the template belt from the surface of the road surfacing material.  
      With the device of the present invention, constant working parameters with high effectiveness can be permitted over the entire working width and in a continuous work process.  
      As additives for achieving the surface properties, different powders and suspensions can be used, preferably the trademark “Permacolor”.  
      The template belt does not lead to the formation of beads or mass displacement on the pressed surface compared to an individual roller.  
      Preferably, the template belt comprises a reinforced, continuous support belt, on which the surface patterns are non-releasably applied and which revolves in the driving direction with corresponding speed.  
      The template belt runs over the roller bodies with preferably the same diameters and one or more tension rollers. This arrangement permits also the use of support belt-free template belts. By changing the belt lengths, different pattern parts can be used.  
      The first roller body has a first vertical adjustment device for regulating the position of the surface of the road surfacing material. A first force regulating element in the form of a spring is integrated in the first vertical adjustment device. The drive of the template belt takes place in a non-positive manner by the first roller body.  
      Preferably the distance of the second roller body from the surface of the road surfacing material is greater than with the first roller body. Thus, the possibility exists that by changing the position of the tension roller, the pressing edges on the template belt can be raised continuously and without beading from the fresh concrete.  
      The second roller body has a horizontal adjustment device for equalizing different belt lengths.  
      The frame is designed in a torsion-resistance construction and preferably has a wheel undercarriage, whereby the wheels drive on a leveled driving surface, for example on rails, directly to the right and left near the surface to be processed.  
      A further design possibility of the undercarriage is the use of a caterpillar undercarriage, which preferably drives on a concrete subgrade.  
      Preferably, the undercarriage, for lateral guiding, has a much greater axial distance than the roller bodies and an edge formwork, which glides between the edges laterally and flatly on fresh concrete bodies.  
      Preferably synchronizing of the drive speed and the work speed takes place via chain drive between the undercarriage and the first roller body.  
      Preferably the device of the present invention has an individual hydraulic drive unit, which engages in the chain drive in a known manner and permits the infinite regulation of the drive speed.  
      Preferably dispensing and processing units for auxiliary material as well as the associated reservoirs are arranged at suitable locations and sequences on the frame and are driven via separate circuits. Distributor and regulating devices are driven by the drive unit.  
      Preferably, the hydraulic circuits have distributor as well as regulation devices, which can be regulated individually and independently from the drive speed.  
      Next, one advantageous embodiment of the invention will be described in greater detail with reference to the sole figure.  
      The device of the present invention for making structured road surfaces includes a frame  1 , a first roller body  2 , and a second roller body  3 , a tension roller  4  disposed between the first roller body  2  and the second roller body  3 , whereby the first roller body  2  and the second roller body  
       3  and the tension roller  4  are arranged on the frame to be axially parallel to one another, and a continuous, flexible template band or belt  5 , which runs around the first roller body  2 , the tension roller  4  and the second roller body  3 .  
      The first roller body  2 , the second roller body  3 , and the tension roller  4  are arranged relative to one another such that the template belt  5  between the first roller body  2  and the tension roller  4  always lies on the surface  6  of the road surfacing material. The part of the template belt  5  between the tension roller  4  and the second roller body  3  is lifted slowly and steadily from the surface  6  at a slight angle by means of a higher positioning of the roller body  3  relative to the roller body  2  with regard to the surface  6  after impressing the surface pattern into the not yet hardened road surface, so that no road surfacing material is torn away.  
      The first roller body  2  and the second roller body  3  have approximately the same diameter.  
      The first roller body  2  has a vertical adjustment device  7  for adjusting the position of the first roller body  2  relative to the surface  6  of the road surfacing material. The vertical adjustment device  7  has a force regulating element  8  formed as a spring for regulating the force exerted by the first roller body  2  on the surface  6  of the road surface and for equalization of minimal height differences in manufactured fresh concrete bodies.  
      The tension roller  4  likewise has a force regulating element  9  in the form of a spring, which serves to regulate a uniform tensioning of the template belt  5 .  
      The second roller body  3  has a horizontal adjustment device  10  for equalizing different template belt lengths.  
      The frame  1  has an undercarriage or travel mechanism  11  with rail wheels and a drive unit  12 , by means of which the device can be driven autonomously. The drive unit  12  is a hydraulically driven engine, whose speed is infinitely controllable, so that the advancement speed of the device can be adapted to various work conditions.  
      The first roller body  2  is drivable by the drive unit  12  and the second roller body  3  is drivable by the first roller body via the template belt  5  tensioned by the tension roller  4 .  
      The first roller body  2 , which is forward in the advancement or working direction is mounted to the frame to be adjustable in height on the frame  1 . With the assistance of the vertical adjustment device  7 , the pressing depth and the pressing pressure of the template belt  5  on the surface  6  of the road surfacing material is regulated. The template belt  5  has the negative of the desired surface pattern and is impressed into the surface  6  of the still not hardened road surfacing material, for example fresh concrete with the addition of different auxiliary materials.  
      One advantage of the invention is that the structure formed on the surface  6  of the road surfacing material takes place by means of a continuous, flexible template belt  5  instead of individual templates. In this manner, a high quality of the produced surfaces is achieved simultaneously with a very high productivity of the continual manufacturing process. The formation of beads that occur with the common use of pressing rollers in not yet hardened road surfacing materials is therefore prevented, such that driving forces and the associated risk of bead formation are avoided or minimized by the selection of a relatively large diameter of the first roller body  2  as well as by the transfer of a torque by the drive  12  onto the first roller body  2 . In addition, the lifting of the template belt  5  after the tension roller  4  from the surface  6  by higher positioning of the second roller body relative to the first roller body  2  and the tension roller  4  likewise effects the avoidance of suction forces that can exist under the template belt  5  and that would destroy the impressed surface. Advantageously, the adjustment angle a between the surface of the road surfacing material and the underside of the revolving template belt is infinitely adjustable. In this manner, a gentle lifting of the revolving template belt from the fresh, not yet hardened concrete of the road surfacing material can be realized, without resulting in an undesired tearing off of material particles.  
      The frame  1  is mounted on an undercarriage  11 , which can travel on rails or on a drive surface  13 . On both sides of the surface  6  of the road surfacing material, leveled rails are placed, on which the undercarriage  11  runs or alternatively, a sub surface is made on which two caterpillar undercarriages travel instead of the wheel undercarriage.  
      The surface  6  of the road surfacing material is made for example by a concrete road paver in a continuous method. The device of the present invention is used as a finishing apparatus to this concrete road paver and likewise continuously presses a surface pattern into the surface  6  of the road surfacing material. The roller bodies  2 ,  3  can be wider than the surface  6  of the road surfacing material.  
     REFERENCE NUMERAL LIST  
       1  frame  
       2  first roller body  
       3  second roller body  
       4  tension roller  
       5  template belt  
       6  surface of road surfacing material  
       7  vertical adjustment deice of the first roller body  
       8  force regulating element  
       9  force regulating element on the tension roller  
       10  horizontal adjustment device of the second roller body  
       11  undercarriage  
       12  drive unit  
       13  driving surface  
       14  power transmission  
      s feed direction of the device  
      a adjustment angle between surface of the road surfacing material and underside of the revolving template belt