Patent Application
20240044092
This application claims priority from Mexican Application No. MX/u/2022/000295, filed Aug. 3, 2022, the entirety of which is expressly incorporated by reference herein.
The embodiments of the present application belong to the field of road safety devices. Specifically, the present proposal is related to a road stud that comprises a single-piece body that has a base with a bottom surface specially arranged to improve its mechanical compression strength and the coupling of the piece with the glue for fixing it to the floor. Likewise, the present proposal has the benefits of storing information related to each road stud, through a dot matrix or in a two-dimensional or three-dimensional bar code.
The concept of road safety refers to the prevention of traffic accidents and/or the minimization of their effects, and also refers to the technologies used for this purpose in any means of land movement or on the road itself.
The use of reflective road studs began to be developed in the 50's of the last century as land communications advanced and due to the increase in speed on roads and highways, which resulted in an increase in the number of accidents; for this reason, safety devices had to be devised on the roads, such as road studs. At first, these were developed made of metal materials that over time turned out to be a trap for car tires due to weather conditions, since instead of slowing them down they became slippery; for this reason, they were replaced by ceramic road studs that turned out to be expensive and also high risk for road safety.
Already in the 70's of the last century, there was a need for new products that did not create problems with vehicle tires and that were resistant to weather conditions in such a way that safety did not decrease and, above all, did not create a problem after the end of its average useful life.
From there arises the use of plastic for its production, a product that is light, but at the same time highly resistant, recyclable and, in turn, noble with the environment and vehicle tires. After several trials and tests with different polymers such as PVC (POLYVINYL CHLORIDE), PMMA (POLYMETHYLMETACRYLATE), PS (POLYSTYRENE), PP (POLYPROPYLENE); some were found to have little resistance to both impact stresses and weather conditions. Therefore, at the end of the 80's of the last century, ABS (ACRYLONITTRILE-BUTADIENE-STYRENE) began to be used to manufacture the casing of the road studs and PMMA (POLYMETHYLMETACRYLATE) to elaborate the reflective used therefore and which meets the properties of safety standards such as:
For this reason, it is common to find this type of device both in cities and on highways, since by themselves, they allow the light of the vehicles that circulate to be reflected, which allows drivers to know the trajectory of the road they are traveling, even facing the absence of public lighting. These types of elements are commonly found on roads, since due to the extension of land that they require, it would be impossible to illuminate them with electric light, especially on unpopulated roads.
Additionally, reflective road studs have the ability to act as speed bumps since, due to their own configuration, they slightly obstruct the passage of vehicles, reducing their speed in descent zones or in determining areas prior to a curve.
To achieve their function, this type of reflective road studs adheres to the road surface, or to the walls that define the adjacent structure of the road, so that the light coming from the vehicle's headlights can focus on them. However, its main use is to complement the markings on the pavement and delimit certain elements adjacent to the road, mainly when unfavorable weather conditions prevail and/or at night to provide the driver with better visibility of the geometry of the road.
The main shape of conventional road studs represents a geometric structure, mainly trapezoidal in shape, with a base that can be square, circular or rectangular depending on the place where they are placed, and they are commonly fixed to the pavement by means of anchors, epoxy adhesives, or bitumen derived from heavy oil during its refining.
The difference that exists between these two glues to adhere them to the surface of the pavement, whether asphalt or concrete, is their degree of compatibility with respect to the base polymer of the road stud casing, which is a base-type terpolymer of ABS (ACRYLONITRILE-BUTADIENE-STYRENE) wherein for the epoxy glue there is a chemical reaction of compatibility with the plastic and the surface is asphalt or concrete. On the other hand, the bitumen, to be applied, requires to be hot at temperatures within a range of 180-200° C., which after being applied on the surface, the road stud is placed and if the plastic is not well designed, it suffers thermal effects that weaken the structure of the polymer, achieving fractures in the structure over time.
In this regard, the design of the road stud of the present application seeks to solve said problems of resistance and reliability, since a road stud is proposed, which, thanks to its alloys of materials used during its manufacture, allows it to increase or withstand higher temperatures during the application of the adhesive on the surface, as well as providing the versatility to use any type of glue. Likewise, derived from its structural arrangement, it improves its capacity to shrink due to heat and impact.
Currently, there are several types of road studs made of different materials, the most common ones are ABS (ACRYLONITRILE-BUTADIENE-STYRENE) road studs, which is a plastic with high impact strength and long durability; reflective lenses, commonly High Impact Acrylic (Methyl Methacrylate), are trapezoidal in shape and have optical grade prisms that have a certain angle and inclination, they can have one or two reflective faces. The prisms are internally metallized by means of a high vacuum process of Aluminum impregnation and their filling is made of an epoxy compound designed for high impact strength.
The closest prior art to the proposal of the present application is the Utility Model Registration MX 3420 B, which belongs to the same owner of the present application. Said registration has as main objective to achieve a mechanical and adhesive fastening means between the glue and the bottom surface of the road stud. However, unlike the current proposal, the body of the road stud in Registration MX 3420 B is made up of two independent pieces that are firmly joined together by means of a series of interlocking “combs” that despite their high resistance, they can be separated during use, likewise, the anchoring channels in said utility model limit their length to the surface of the base, so that the fastening of the cover depends solely on its internal coupling with the base. Additionally, the present proposal uses a single-piece main body whose anchoring channels comprise the entire bottom surface of the base but are divided in its middle part by cross-sectional supports. Likewise, it presents a series of primary and secondary tensors that increases its central compression strength from top to bottom. Another advantage of the present proposal compared to the prior art is the implementation of an information storage medium related to each road stud, through a QR barcode, preferably three-dimensional.
Another close prior art is utility model registration MX 4002, which also belongs to the owner of this application. It describes a reflective road stud that has a lightweight, strong, and inexpensive one-piece body that has two channels in the bottom surface of the base that function as a “dovetail” that, when an adhesive is applied to, forms an adhesive and mechanical anchoring means between the base of the road stud and the glue. Based on said proposal, the road stud of the present application implements a similar structure at its base, however, it adds cross-sectional supports between the anchoring channels, thereby increasing its central compression strength from top to bottom. Also, the present proposal uses a surface with vaulted cavities for the placement of glue, and a greater roughness on the flat surface for greater adhesion and coupling with the adhesive. Additionally, an information storage medium related to each road stud is implemented, through a QR barcode, preferably three-dimensional.
None of the current proposals describes a road stud that has a chemical composition based on ABS with a reflective element that uses PC (POLYCARBONATE) as a reflective polymer, forming a piece with greater impact strength with a good degree of reflectivity, and a grooved surface to improve the degree of adhesion of the epoxy glue. As well as the use of channels for adhesive with cross-sectional supports to increase the central compression strength of the piece, from top to bottom, improving its mechanical compression strength and, in turn, increasing the coupling strength of both the piece with the glue and of the glue against the concrete or asphalt layer. Also, none of the current proposals implements a QR information storage code, which provides information about materials, life span, reflectivity rates, etc., of each road stud during the manufacturing thereof.
The present proposal and its embodiments generally describe a road stud with an improved fixing structure for road use that can be used in city roads and highways, both for signaling and to reduce the speed of traffic of the vehicles that circulate on them. This is achieved through a main body that has a top surface preferably trapezoidal in shape, made in one piece that has at least two anchoring channels and a series of vaulted cavities, arranged to receive an epoxy glue or bitumen inside which, together, form a means of anchoring of the piece to the pavement both mechanically and adhesively. In a preferred embodiment, the proposed road stud comprises a trapezoidal-shaped piece that has a preferably rectangular base (without being limited to that shape), with at least two anchoring longitudinal channels that pass through the inner surface of the road stud base from one end to the other and wherein, in turn, each channel is divided into at least two parts by means of a perpendicular support or crossbeam that increases the adherence of the epoxy glue or bitumen in the inside forming an adhesive and a mechanical bond of the glue with the road stud base as well as with the pavement or the asphalt.
Also, in the preferred embodiment, the edges of the anchoring channels are angled, which forms a “dovetail” between the adhesive and the base of the road stud, since the adhesive is introduced inside these, adjusting to the defined gap so that it can be tightly fitted thereto preventing it from getting out or moving, this feature forms both a mechanical and adhesive bond that keeps the body of the road stud firmly attached to the adhesive and in turn to the pavement or asphalt.
The preferred embodiment also has crossbeams or supports that are located perpendicular to the longitudinal anchoring channels, preferably in the central part of each longitudinal channel of the road stud. Said crossbeams are also angular, which contributes to the formation of “dovetails” between the adhesive and the bottom surface of the road stud.
Thanks to the intervention of the crossbeams and the longitudinal anchoring channels, the body of the road stud increases its compressive strength since the body of the road stud increases its maximum strength that it can withstand under a crushing load, so the force exerted on a point of the road stud, exerted by the passage of vehicles, and even heavy trucks, cause the piece to deform as necessary without actually breaking, which allows it to absorb the force exerted by vehicles without the latter being transmitted throughout the piece and the adhesive, preventing the road stud from detaching from the pavement without breaking.
In order to increase the mechanical strength of the road stud, in its preferred embodiment, the base of the road stud includes the inclusion of primary and secondary tensors, formed from vaulted cavities, which together with the main tensor, increase its thickness in order to balance the impact strengths wherein instead of having only four dissipation tensors (main or primary tensors) of impact energy, with the incorporation of secondary tensors, the corresponding compression support and bending strength of the piece is doubled, keeping the same formulation of its production and only modifying the distribution of the strengths it receives from there to give a longer half-life of the road stud.
In the preferred embodiment, the present road stud also has a series of substantially rectangular openings, which can be of any shape that fulfills this function, distributed at each side end of the base of the road stud in an equidistant manner to be also covered by the epoxy glue or bitumen, these openings define cavities that are separated from each other by crossbeams that contribute to improving the adherence of the glue inside as well as to increase its compression strength, as is the case with the crossbeams of the longitudinal anchoring channels.
In a second embodiment, the bottom surface of the base of the road stud has at least four rectangular-shaped longitudinal channels with at least one pointed end, without being limited to this shape, which are distributed in the central part of the base of the road stud close to a central circular junction.
In a third embodiment, in addition, on the bottom surface of the base of the road stud there are at least four channels distributed in the central part that are preferably rectangular with pointed ends, which allows them to cover practically the entire bottom surface, also, small, preferably triangular openings are located that cover the free spaces left in the central part. It is important to mention that all these openings can be of any shape that allows them to be distributed over the entire central part of the bottom surface of the road stud.
The foregoing aspects and many of the advantages of this proposal will be better understood when the following detailed description is consulted and considered in conjunction with the accompanying drawings, wherein:
In the following, the embodiments of the present proposal will be described with reference to the drawings. Identical elements in the several figures are identified with the same reference numbers.
Detailed reference will be made to each embodiment of this application. The embodiments are provided by way of explanation and are not intended to be limited thereto. In fact, those skilled in the art will appreciate by reading the specification hereof and viewing the accompanying drawings that several modifications and variations may be made thereto.
In the present proposal, there is an innovative product that differs from the current art since the reflective element used preferably has a PC (POLYCARBONATE) composition as raw material, with which the degree of reflectivity has been exceeded with much higher values compared to PMMA (ACRYLIC) and ultrasound welded.
Two important modifications to increase the physical-mechanical, thermal, and reflectivity properties of the proposed road stud are the following:
Referring now to
The rounded edges (1c) help reduce the impact stress exerted by vehicle tires on the body of the road stud (1) when they come into contact with it, which minimizes the risk of it coming off the pavement or asphalt. With regard to the handling cavities (3), these are deeper in relation to the prior art, which makes it easier to insert the person's fingers once the adhesive is applied for its subsequent placement on the pavement or asphalt.
As mentioned in previous paragraphs, the preferred embodiment of the present invention comprises only one housing area (2) on one of the longitudinal sides (1b) of the road stud, which is why, the opposite longitudinal side of the main body (1) defines high embossment pattern (4) which can be arrows in the opposite direction, as shown in
Thanks to the trapezoidal structure of the main body (1) of the preferred embodiment of the road stud of the present application, the calculation of the gravity center was determined as follows:
In order to obtain the gravity center, as well as the impact, compression and strain stresses from the gravity center equation, the experimental data of the closest prior art road stud with respect to the current proposal were considered and the corresponding values are shown.
With the increase in the gravity center in the present design, final physical-mechanical properties are achieved that allow for a better product with technological support.
Derived from the previous analysis, in
It is important to mention that both the inner walls (10) of the longitudinal channels (8) and the inner walls (11) of the crossbeams (9) are angled with respect to the vertical, see
Thanks to the intervention of the crossbeams (9), the body of the road stud increases its compressive strength since the body of the road stud increases its maximum stress that it can withstand under a crushing load, so the stress exerted on a point of the road stud exerted by the passage of vehicles, and even heavy trucks, cause the piece to be deformed as necessary without actually breaking, which allows it to absorb the stress exerted by the vehicle tires without the latter being transmitted through the entire piece and the adhesive preventing the road stud from detaching from the pavement without breaking. Also, unlike the prior art, the longitudinal channels (8) are now placed more towards the center of the base (7) so that they do not receive the stresses that generate fractures in the system.
As shown in
With the incorporation of the primary (8.1) and secondary (8.2) tensors, it will be possible to have a greater grip of the glue, be it bitumen or epoxy adhesive, and therefore the distribution of stresses to be distributed to obtain greater bending and compression strength as shown in the following table:
The increased capacity of the bending property of the preferred embodiment is reflected in the impact distribution.
In the case of compression, the standard requires that the piece not be deformed by compression at 3 mm strain, with the present proposal there is a compression strain of 10000 Lbf/inch2 of 1 mm, with which it is placed within of the standard and the design tensors and impact distributors are complying with the regulations.
Additionally, the base (7) of the road stud has a series of openings (15) that define an internal housing of substantially triangular shape, which are formed from the faces of the trapezoidal surface of the main body (1). It is important to mention that all the openings (15) can be of any shape and size that allows them to cover the largest possible area of the base (7) of the road stud. Also, each opening (15) is separated from the other by means of crossbeams or perpendicular supports (15a) that have an angled inner wall to improve adhesive adhesion.
In addition to the above,
With all the architectural structural modifications, it was possible to increase the strengths that the road stud can receive during its application and therefore continue to support innovation, research and development of more sophisticated products with technological support. In addition to the architectural structural changes of the modification to the molecular structure of the polymer with impact modifiers and the process conditions to increase the intrinsic properties of the new alloys in improvement of the physical-mechanical, thermal and reflective properties of our product.
Impact modifier agents that would make an alloy with the main structure of the engineering plastic that we use, which is ABS (ACRYLONITRILE-BUTADIENE-STYRENE), were used within the selection that was made mainly to the physical-mechanical impacts that the piece undergoes plus the application conditions with the softening temperature, the following results were obtained, which are presented in the following Table 2, using polymeric impact modifiers that modified the intrinsic properties of glass transition temperature (Tg), the coefficient of linear thermal expansion (CLTE), its flow rate or rheological system (MI),the density (Q) that modifies its elongation (E) and the strain stress (σ) where we used two different impact modifier additives MIMP-1 and MIMP-2, which allows the process to have greater strength in the viscoelastic properties during its transformation depending on its temperature, speed and pressure during the process, helping to improve the rheology and thixotropy of the injected pieces, in terms of its final physical-mechanical properties and the corresponding thermal strength, they increase especially during its placement, since with epoxy glue, the heat emanates from the reaction of the adhesive resin, and we increased the strain strength with the use of bituminous resins that are placed at a temperature of up to 200° C. and after being applied to its surface, the road stud is placed, whereby we improve the structural development on the CLTE and the softening temperature to increase its strain strength and therefore the final environmental physical, mechanical and thermal properties to which the road stud will be subjected, which are presented in Table 3.
It is noted that the strains decrease in comparison with the molecular structure of the modified ABS that is used and that with the new structure an improvement in the loss of properties is achieved to give the road stud a longer half-life according to the results of the system.
The nomenclature we will use will be:
Another innovation within the present invention results in the incorporation of a QR (Quick response) identification code, which is used as a module to store information in a dot matrix or in a two-dimensional barcode. In this particular case, as can be seen in
This data will be provided so that users who make use of this type of road stud have general information on the quality of the product and know the traceability thereof for any anomaly.
By having the QR code (17) engraved, each piece becomes unique in the market, and this provides a competitive advantage, since its performance and geolocation can be measured in the field to provide better service and monitoring, in addition to guaranteeing the quality of the product in the field.
The reading process of the QR identifier (17) can be carried out through any QR reader device, which can range from portable devices that include a laser scanner and a small screen to mobile phones to even devices specially designed to, in addition to read the QR code, take data in the field such as the current lumens of the reflective media.
In
Finally, in
The base (7) of the road stud also has a series of channels (18) distributed in its central part, at least four, which are preferably rectangular with pointed ends that allow them to cover practically the entire bottom surface of the base (7) to cover as much surface area as possible. Likewise, the base (7) has small openings (19), preferably triangular in shape, to cover a greater surface area of the base (7), although they can be of any shape, so that the free spaces left in the central part are covered from the base (7). It is important to mention that all these openings can be of any shape that allows them to be distributed over the entire central part of the bottom surface of the base (7) of the road stud.
This embodiment has greater mechanical support on the dovetail in the form of a circular joint and making it towards the center of the mass of the road stud to withstand both impact strengths and weather conditions as well as temperature withstand when gluing them to the surface, must of all when it comes to bitumen at a 200° C. temperature. This impact center, which is a circle (17), is to distribute the stresses in a balanced way throughout the surface in such a way that they dissipate quickly without deforming or forcing the piece and therefore have a greater oscillatory and precipitator stresses strength.
The bars or tensors that will support the impact, compression or strain stress are also seen, and at an angle of 120°, the distribution of the energy of the impact emanates from the circle (17) towards these tensors in such a way that it will tend to distribute and return the trapezoids of the system that, together with the glue, will form a set of elongation and resilience of the piece, cushioning the impact, an improvement of 18% is expected, and consequently an increase in the half-life of the piece between 12.5 to 13.9%.
The dovetail is modified towards the center to give greater impact stress strength and therefore increase the effect of elongation and resilience, giving the piece a longer half-life, and the stresses that are generated at the juncture of the dovetail will tend to be more circular to better distribute the stresses and therefore have a better mechanical, physical and thermal strength to the expansions that it will suffer during its application in the field.
The dovetail is transferred towards the center, it was previously at the limits of the reflective element, now it is placed towards the center so that it does not receive stresses that generate fractures in the system, as shown in the figure.
With respect to the crossbeams or supports (9), these are located perpendicular to the length of the anchoring channels (8), preferably in the central part of each anchoring channel (8). Said crossbeams (8) also have an angular wall (11) which contributes to the formation of “dovetails” between the adhesive and the bottom surface of the base (7) of the road stud. Thanks to the intervention of the crossbeams (9), the body of the road stud increases its compressive strength since the body of the road stud increases the maximum stress that it can withstand under a crushing load, so the stress exerted on a point of the road stud exerted by the passage of vehicles, and even heavy trucks, cause the piece to deform as necessary without actually breaking, which allows it to absorb the stress exerted by vehicle tires without the latter being transmitted throughout the piece and the adhesive preventing the road stud from detaching from the pavement without breaking. With respect to the openings (15), the QR identification code (17) and the edges (16) described for the preferred embodiment, these are also used in said second embodiment.
Although preferred embodiments have been shown and described, modifications thereto can be made by one of skill in the art without departing from the scope or teachings herein. The embodiments described herein are only exemplary and are not limiting.
Many variations and modifications of the road stud arrangement are possible within the scope hereof. For example, the sizes of the base both in width and length, the materials and distributions of the cavities can be varied. Also, the angle of inclination of the housing channels and of the supports can be varied to improve their force of attraction. The number of anchor channels, supports, as well as the inner angle of the walls thereof, can be varied. Consequently, the scope of protection is not limited to the embodiments described herein, but is only limited by the following claims, the scope of which will include all equivalents of the subject matter of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| MX/U/2022/000295 | Aug 2022 | MX | national |
