FR2522034A1 - MARKING STRIP FOR ROAD OR SIMILAR SIGNALING - Google Patents

Abstract

THE INVENTION CONCERNS A MARKING TAPE FOR HORIZONTAL OR SIMILAR ROAD SIGNALING ARRANGED ON THE R SURFACE OF THE PAVEMENT, MADE IN A PRE-MOLDED PLASTIC MATERIAL BOND ON THE SURFACE OF THE PAVEMENT BY MEANS OF A THIN LAYER OF ADHESIVE 4 ARRANGED BETWEEN SURFACE T AND BAND 1. ACCORDING TO THE INVENTION BAND 1 IS AT INTERVALS SHAPED UPWARDS TO ACHIEVE SUCCESSIVE TRANSVERSAL PROTUBERANCES T OF SENSITIVELY TRAPEZOIDAL SHAPE IN LONGITUDINAL SECTION, EACH PROTUBERANCE 2 PLACES A SENSITIVELY TRAPEZOIDAL SHAPE IN A LONGITUDINAL SECTION, EACH PROTUBERANCE T PLACES A SENSITIVELY TRAPEZOIDAL SHAPED T PROTUBERANCE IN LONGITUDINAL CUTTING SUMMIT LIMITED BY FRONT AND REAR 2 AND 2 WALLS INCLINED SO AS TO PRESENT AN ACUTE ANGLE TO THE VERTICAL. THE INCLINED WALLS 2, 2 ARE INCRUSTED WITH RETRO-REFLECTIVE BEADS 3, AND THE SURFACE OF FLAT ZONE 2 AT THE TOP IS COMPARABLE TO THAT OF LOW ZONE 1 OF THE BAND BETWEEN TWO SUCCESSIVE PROTUBERANCES. APPLICATION: HORIZONTAL ROAD SIGNALS.

Description

351.037 12522034

  MARKING STRIP FOR ROAD OR SIMILAR SIGNALING

  The present invention relates to the distinctive marking of directions on motorways, airports and other surfaces, by means of thin marking strips glued to the passage surfaces or the like and incorporating

  successive protuberances spaced apart and provided with retroreflective materials

  The invention relates more particularly to marking strips.

improved of this type.

  Because of the extremely low angle between an automobile headlight and the road it illuminates, only a very small percentage of the light is reflected back to the driver. The problem is complicated by the fact that the surface of the roadway is generally practically flat and has poor reflective characteristics, black asphalt being the worst type of pavement in this respect Average visibility of the pavement when the headlights of the car are in low beam at night is usually

  reduced to about 30 meters There has been considerable progress in

  white bands on the road; but even a recently painted line

  it does not increase the visibility of the roadway beyond sixty

  In addition, when the road surface is wet in the rain,

  is reduced even with a newly painted line, a few dozen

  meters, the thin layer of water that covers the pavement and the painted surface acts as a mirror that reflects almost all the light from the headlights of automobiles away from the driver.

  if it is equipped with excellent white bands, the road looks like

  only to a black hole for the driver, this being the essential reason

  for which he is so insecure to drive at night in the rain.

  It was concluded that the only practical solution to this problem of low

  visibility is to use raised road markings that make

  Normally used in some areas, especially in warm regions, such marking is rarely used in snowy areas because of the destructive effects of snowploughs We tried to overcome this difficulty by means of a frame or a slope

  intended to guide the plow's plow upwards and above the mark.

  age, but the adoption of this marking has not been extended because it is generally impossible for some markings to withstand the harsh treatment of snowplows. expensive and are usually widely spaced from each other In addition they are only useful at night when illuminated

351.037 2 2522034

  by the headlights of automobiles and are faintly visible, if not

  at all, the day by the drivers, which requires additional marking

  additional or obtained by means of a painted line or a line of

  plastic for guiding the pipe in daylight.

  However, for many years, many types of

  raised pavement floor whose main purpose was to guide the self-driving

mobilists at night.

  These devices generally have little or no detection or utility during the day and are only used at night when illumination due to automobile headlights is redirected backward by internal reflection.

  on themselves so that they can be seen by the driver of the vehicle.

  These devices often affect the shape of pimples or mounds containing

  surfaces or retro-reflective elements More recently; a configuration in the shape of bulges has been adopted so as to present less danger for the vehicles passing over it, some of which have the form previously mentioned to guide the snowplow but without being

  However, such devices, as already mentioned, are costly

  and must necessarily be relatively widely spaced from each other on the roadway, which has the disadvantage, in the light of

  lighthouses at night, although apparently bright, to

  light and not the actual continuous line that is desirable or even a dashed line, they are usually not visible at all.

  for drivers at any distance.

  In order to obviate some of the aforementioned and other disadvantages, relatively low markings have been proposed, such as those described in US Pat. Nos. 3,785,719, 4,035,059 and 4,279,471. separate individual elements which are still expensive to manufacture and which must always be used with a relatively large spacing between them if realistic efficiency in

  cost and operational aspects.

  A more appropriate approach to overcoming these problems is to use

  a thin flexible sheet containing a series of raised markings of very low height as described for example in US patents

  3,920,346, 4,040,760 (FR 2,274,736), 4,069,787, 4,145,112, 4,182,548, 4,236,788.

  With the exception of the second and third patents

  sheet has its main part constructed to be transparent to the light

  This makes the devices subject to serious light loss during use due to friction and accumulated dirt. According to the third patent cited, successive protuberances are made in the teeth.

351.037 3 2522034

  in a thin strip fixable on the road, and, although this solution is satisfactory, there have been shadow effects when they are turned towards the sun and a change in the results after wear due for example to a use prolonged and / or deterioration caused by snowplows, which does not allow to use them in daylight, at nightfall

  or in other adverse conditions as it would be desirable.

  In the case of successive protuberances of substantially triangular

  as described in French Pat. No. 2,274,736, for example, a

  prolonged demonstrated that under certain ambient light conditions, the

  The road surface becomes difficult to observe for drivers.

  In particular, if the marking strip is oriented in such a way that the driver generally faces the sun on a cloudless day, the contrast between the strip and the roadway is so low that the strip becomes difficult to distinguish. the sun casts a shadow of each protuberance in the low zone between the protuberances The walls of the protuberances observed by the driver, moreover, are all in

  shadows and appear black, resulting in a great difficulty in distinguishing

  war the band of the black surface of the road The appearance of darkness or the

  low contrast between the marking tape and the pavement is

  that the sun makes a dim angle a day without a cloud.

  It has been fortuitously discovered that by changing the shape of the protuberances, that is to say by passing from a triangular shape to a trapezoidal shape,

  but only with a length of protuberance depending on the spacing pre-

  seen between two successive protuberances, we could completely obviate this problem, and simultaneously it brought many advantages such as a better wear resistance, a longer life to the friction especially due to snowplows The flat top of protuberances now

  trapezoidal shape, if the dimensions and spacing are appropriate,

  flexes sunlight and beautifully reduces shadow effects.

  The present invention therefore relates to a new marking structure

  which is not subject to the aforementioned drawbacks but which can

  during obviate the effects of shadow and discontinuity while resisting better

  wear and which can be used under adverse ambient conditions.

  ble. The invention also relates to a flexible strip of ground marking or the like which is clearly visible as a continuous line in daylight ambient light and which is also retroreflective for the headlights

  cars the night even in the pouring rain.

  The subject of the invention is also a flexible strip of marking

351.037 4 2522034

  both a configuration and a low height but sufficient to withstand

  to the tearing effect of snowplows.

  The invention also relates to a very visible highway marking strip in night driving, with a long life and good retro-reflective characteristics throughout the lifetime.

  The invention also relates to a new general purpose marking.

  In summary, according to one aspect of the present invention, for the surface

  pavement or the like, the marking strip for the horizontal signaling

  zontal, is made of a pre-molded flexible plastic material bondable on said surface by means of a thin layer of an adhesive disposed between said surface and the strip, said strip being at intervals deformed upwards to achieve successive transverse protrusions of trapezoidal shape in longitudinal section, having a substantially flat area at its apex bounded by front and rear walls inclined to have an acute angle with respect to the vertical, said inclined walls being encrusted with retroreflective beads; reflecting, and the surface of the flat area at

  vertex being comparable to that of the lower zone of the strip between two

successive bursts.

  The present invention will be better understood and other objects, advantages and features thereof will become more clearly apparent on reading the

  description which follows given in a non-limiting way and to which a board

drawings is attached.

  Figure 1 shows in longitudinal section the preferred embodiment of

invention and

  Figure 2 is a similar view with a modification.

  Referring now to FIG. 1, the thin flexible strip of plastic material for road marking 1 is glued to the roadway or to any other surface R by means of a lower adhesive layer.

  have already been described elsewhere but will be specified below.

  As indicated previously, the structure substantially sawtooth

  affects the shape of a succession of trapezoids T (in longitudinal section)

  protruding and having a flat top 2 limited on both sides by

  2 'and 2 "inclined ribs extending transversely with respect to the band 1 and all preferably molded in the thin plastic material of the band 1,

  protuberances projecting at intervals above the band.

  A preferred range of acute angles of inclination (or downward slope)

  allows better use as described below.

  The two inclined walls 2 'and 2 ", at least, bear one or more

  layers of retro-reflective or similar beads 3.

351.037 5 2522034

  Thus realized, instead of observing an apparent extension of the part

  on one side of a protuberance merging continuously with the part of the pro-

  following tubement etc, as described in US Patents 3,920,346, 4,040,760 and 4,069,787, dads the case of the trapezoidal protuberances of Figure 1, there is interruption of the apparent melting of the walls due to the length of the vertex 2 of the trapezoidal protuberance T In light of the

  day, even with the sun in the face, when the flat surface of the top 2 reflects

  in all directions to the same apparent surface as the part observing

  which is in the shade, the visual effect of the sun's shadow becomes sufficiently

  reduced to allow band 1 to be truly distinctive visually

  This makes it possible to use the marking belts

  daylight and twilight unlike previous bands.

  The increase in the surface would give a better contrast in daylight between the strip and the pavement, but the apparent brightness at night in

  retro-reflection of automobile headlights would decrease The condition for ob-

  to maintain equal apparent surfaces is filled when the width of the flat area of the vertex 2 of the trapezoidal protrusion T is substantially

  equal to that of the low zone 1 'between two successive protuberances

  Preferably, the height of the protuberances is equal to a small

  fraction of the length of the protuberance including about 1/6 thereof.

  Tests have shown the effectiveness of such a band to increase the

  3 hours at night and have good visibility on the day even if there is shade These tests focused on a band with the following characteristics: length of the flat top (2) S 7.6 mm length of the lower zone (1 '): 7.6 mm crown height: 1.2 mm angle at S between 0 and 450 glass beads (3): 0.12 to 0.25 mm in diameter

N = 1.9

  Observed with a light source directed at an angle of about 850 from normal, the amount of back-reflected light on the 2 'or 2 "surfaces was excellent. Located on a R-road and observed late in the afternoon. - midday a day of cloudless sun, with the bands oriented in such a way that important shadows of the protuberances carry in the low zones 1 'between them, seen with an angle of 45 to 850 with respect to the normal in the general direction of the sun, the bands appear clearly clear

351.037

  compared to the dark pavement In retro-reflection at night, it was determined that at 400 meters, a driver could see the top row of pearls of

  0.25 mm in diameter on the walls of the protuberances.

  In FIG. 2, the retroreflective beads 3 have been disposed over the entire surface of the strip 1 and in particular embedded in the

  flat area 2 at the top of the protuberances.

  The marking belts conforming to the

  my to the invention using a mold machined for example from a piece

  of aluminum 10 cm wide and 1.3 cm thick The hollow of the samples

  previously described had a length of 7.6 mm at the top, cor-

  corresponding to the vertices 2 of the bands, with walls inclined at 300, corresponding to

  laying at 2 'and 2 "and a depth of 0.12 mm The mussels were spaced from

  1.52 cm First, narrow strips of 0.13 mm thick polyethylene are

  on the sloping walls by means of a suitable adhesive 4 resistant to

  heat The mold is then heated to about 1350 ° C and the

  glass spheres (0.25 m in diameter, refractive index N = about 1.9) by pressing them into the softened polyethylene After cooling, the excess microspheres are removed leaving only those with 40% u of the diameter inlaid in polyethylene Then poured a plastisol of what is called "PVC" containing a white pigment, in the hollow of the mold to cover the whole of about 0.4 mm The whole is placed in a furnace while

  a sufficient time to ensure that plastisol is taken at a temperature of

  1650 C in order to melt and then solidify the casting After cooling

  the mold is removed, the microspheres are now embedded for about 60% of their diameter in the inclined walls of the protuberances

  of the plastic sheet.

  Of course, any modification made by those skilled in the art in the

  same spirit would not be outside the scope of the present invention.

351,037 7

Claims (5)

R E V E N D I C A T I 0 N S   1 Marking tape for horizontal or similar road signs arranged on the surface (R) of the roadway, made of a plastic material   pre-molded bondable on said surface by means of a thin layer of an adhesive   sif (4) disposed between said surface (T) and the strip (1), characterized in that said strip (1) is at intervals deformed upwards to realize   successive transverse protuberances (T) of substantially   longitudinal section, each protuberance (T) having a zone (2) substantially flat at its apex bounded by walls (2 'and 2 ") before and   rearward inclined so as to have an acute angle (a) with respect to the   the so-called inclined walls (2 ', 2 ") being encrusted with retro pearls.   reflective (3), and the surface of the flat area (2) at the apex being   to that of the lower zone (1 ') of the strip between two protuberances successive rancours.   Strip according to Claim 1, characterized in that the said angle   acute (a) is between 0 and 450.   3 Band according to claim 1 or 2, characterized in that the height of said protuberances is equal to a fraction of the length of the said flat area (2) at the top.   Strip according to claim 3, characterized in that the said length   it is of the order of a few millimeters and the said fraction of the order sixth.   Strip according to any one of claims 4 characterized in   what retro-reflective beads (3) are also embedded in said flat zone (2) or vertex.   Strip according to one of Claims 1 to 5, characterized   in that said pearls (3) are encrusted for about 60% of their diameter.   meter in the material with which is made the said strip.