Patent Publication Number: US-2009232596-A1

Title: Traffic device, such as a roadside post

Description:
The invention relates to a traffic device, such as a roadside post, provided with an indication means having a visible area and with a cleaning device for cleaning the indication means. 
     Such a traffic device is known in the form of a roadside post, in which the indication means is a reflector and the cleaning device is designed for cleaning the visible area of the reflector. In use, these roadside posts are positioned alongside motorways. Over time, the visible area of the reflector becomes soiled due to deposits as a result of the weather and the dirt from passing traffic. The cleaning device is intended to keep the visible area clean and to maintain a good reflective action of the reflector. 
     One drawback of the known traffic device is that the visible area is not cleaned to a sufficient degree by the cleaning device. This is caused, inter alia, by the fact that with the known traffic device, the frequency of the cleaning operation carried out on each part of the indication means is very low. In addition, during the cleaning operation, the cleaning device uses a substantially constant pressure on the visible area of the indication means. The result thereof is that, during a cleaning operation, part of the dirt present on the visible area is removed and the other part of the dirt is pressed onto the visible area in such a manner that the dirt sticks to the visible area. Furthermore, the dirt is wiped across a large part of the visible area as a result, without the dirt being removed from the visible area. 
     A further drawback of the known tic device is the fact that the cleaning device becomes soiled quickly, as a result of which it tends to soil the visible area rather than clean it during a cleaning operation. The solution which is proposed in this case is to have an individual clean or replace the cleaning device. However, as the cleaning device of the known traffic device becomes soiled so quickly, this will result in labour costs which are so high that this traffic device becomes too expensive to be maintained. 
     Furthermore, the known traffic device has the disadvantage that the cleaning device is of a complex construction. Consequently, the costs of producing the traffic device are too high to be able to compete with the traffic device without cleaning device which are at present being used in practice. This traffic device without cleaning device is cleaned once every two months by an individual, which leads to high labour costs, is dangerous for the individual in question and causes tailbacks. The higher purchase price for the traffic device with cleaning device has to be recouped over time by the savings which the traffic device with cleaning device produces in terms of cleaning. Due to the high manufacturing costs of the known traffic device, this recoupment time is long. 
     In addition, the cleaning device contains many moving parts in order to drive it, as a result of which a lot of energy is lost and a lot of wear occurs. Furthermore, the cleaning device uses many movement conversions in order to drive it, for example from a rotating to a translational movement, which results in a significant loss of energy. 
     Furthermore, a traffic device according to the preamble of claim  1  is known from GB 780.236. This publication discloses a round reflector having a plurality of reflecting studs. This reflector is provided with a rotor which is driven by the wind. The rotor is provided with wiper elements for keeping the reflecting studs clean. According to one embodiment, the wiper elements are provided on the radial vanes of the rotor, according to another embodiment the wiper elements are provided on radial dry cores for a vane ring. In both embodiments, the wiper elements have a longitudinal direction which extends in the radial direction of the rotor and the wiper elements are attached to the rotor over this entire longitudinal direction by a longitudinal side in order to point to the reflecting studs to be cleaned in the axial direction from this attachment. The wiper elements are significantly shorter in the axial direction than in the radial direction. 
     It is an object of the invention to provide a traffic device in which the cleaning device provides an improved cleaning action of the visible area of the indication means. It is a further object to provide a traffic device, the manufacturing costs of which are so low that it is the most advantageous solution compared to the known traffic devices. It is yet a further object to provide a traffic device in which the cleaning device becomes soiled less quickly. In addition, it is an object to provide a traffic device in which less loss of energy occurs during driving of the cleaning device. 
     This object is achieved by the traffic device according to the invention, which may be a roadside post and is provided with an indication means having a visible area and with a cleaning device for cleaning the indication means, in which the cleaning device comprises a plurality of cleaning elements, 
     in which each cleaning element comprises an elongate and flexible body, characterized in that this elongate, flexible body is attached to the traffic device at a longitudinal end and from there extends in a cantilevered manner to the opposite other longitudinal end; and in that the longitudinal direction of the body of the cleaning elements in each case extends along the visible area in such a manner that the body can swish across the visible area with its length in order to clean it. 
     Since each of the cleaning element bodies can sweep across the visible area with its length (the cleaning operation), a large contact surface with the visible area is established by a relatively small number of cleaning elements. By the swishing action of the cleaning elements, a high-energy contact with the visible area is achieved, with the cleaning elements being in contact with the visible area under a variable pressure. Consequently, the dirt is virtually beaten off the visible area, which leads to less dirt remaining stuck to the visible area as a result of the cleaning operation. This offers the advantage that dirt is not smeared across the visible area and is not collected by the cleaning elements. As a result, the cleaning elements become soiled less quickly. In addition, the dirt which is stuck to the cleaning elements is beaten off the cleaning elements by the high-energy contact between the cleaning elements and the visible area. 
     With this embodiment of the traffic device according to the invention, the cleaning elements for bringing about the swishing movement are driven by air flowing past the cleaning elements. This flowing air is caused, inter alia, by traffic passing the traffic device. As a result, a high frequency of the swishing movement of the cleaning elements across the visible area is achieved. The traffic devices near busy roads become soiled the most. As the frequency of passing traffic is very high on these roads, the frequency of the cleaning operations carried out by the cleaning device in the case of a traffic device according to the invention which is placed along one of these roads is also very high. 
     The cleaning elements are preferably flexible to such a degree and have a length which is such that a swishing action is brought about by the air displacement of a vehicle passing at a distance of 5 metres at a speed of at least 50 km/hour. The traffic device according to the invention furthermore has the advantage that the cleaning device does not require any moving parts in order to be driven and has virtually no movement conversions, as a result of which very little loss of energy occurs. Furthermore, as a result of the simple construction of the traffic device, the manufacturing costs thereof are low. Preferably, the cleaning elements are flexible to such a degree and they have a length such that the swishing action is brought about by the air displacement of a wind from wind force 4 Bft. 
     In an embodiment according to the invention, the device comprises displacement means for displacing the cleaning elements with respect to the visible area. The advantage thereof is that the frequency of the cleaning operations is not dependent on circumstances which cannot be controlled, such as the wind and passing traffic. By means of the displacement means, the swishing by the cleaning elements is controlled by the traffic device itself. 
     The indication means may comprise projections, which projections project from the visible area in such a manner that the projections touch the cleaning elements during relative displacement between the visible area and the cleaning elements. The projections serve to initiate and amplify the swishing action of the cleaning elements. Furthermore, this has a positive effect on achieving a good contact between the cleaning elements and the visible area. 
     In a further embodiment according to the invention, the indication means is circular and the indication means comprises a centre and outer circumference. Through the circular indication means, it is possible to achieve a relative displacement between the cleaning elements and the indication means in a simple manner by means of a rotary movement. The cleaning elements in this case extend preferably substantially radially. The cleaning elements can be secured near the centre of the circular indication means and/or secured near the outer circumference of the circular indication means. 
     In another embodiment according to the invention, the cleaning device has an outer ring which is situated coaxially with respect to the circular indication means, which outer ring has a larger diameter than the circular indication means and in which at least some of the cleaning elements are attached to the outer ring, the outer ring and the indication means are arranged so as to be able to rotate with respect to one another and the displacement means are designed for rotating the outer ring and the indication means with respect to one another. In this way, a simple construction effects the rotary movement between the cleaning elements and the indication means with respect to one another. 
     The traffic device according to the invention may comprise a continuous air duct and the displacement means may comprise a rotor, the rotor being designed to be driven by the air flowing through the air duct. Air displacements caused by passing traffic, inter alia, are in this embodiment used in an advantageous way for driving displacement means in order to effect the relative displacement between the cleaning elements and the indication means. The outer ring may be arranged so as to be able to rotate and the displacement means may comprise first vanes provided in the outer ring. In this case, the outer ring is driven by the air displacements in order to rotate with respect to the indication means. It is also possible for the displacement means to comprise at least one second vane situated in the air duct. 
     The cleaning elements can be removably attached to the traffic device. The cleaning elements can thus be replaced in a simple manner. The detachable connection can, inter alia, be formed by a snap connection or an adhesive connection. At least some, and preferably all, of the ends of the cleaning elements attached to the traffic device are connected to one another. This is advantageous, inter alia, for quickly detaching and attaching the cleaning elements to the traffic device. The cleaning elements are preferably transparent in order not to restrict the view of the indication means. Furthermore, the cleaning elements overlap one another, at least partially, in use. This results in the cleaning elements touching one another while swishing, which leads to the cleaning elements cleaning one another. 
     In one embodiment according to the invention, the displacement means comprise a solar cell and an electromotor. In this manner, the indication means can be cleaned independently of air displacements. The indication means may comprise at least one LED as light source. The LED may be powered by a solar cell or by a power generator connected to the displacement means, such as a dynamo. In this context, it is also possible to provide the traffic device with a battery. Furthermore, the elongate body of at least some of the cleaning elements may comprise bristle-like parts, which bristle-like parts extend from the body in the direction of the visible area The traffic device may comprise energy-storage means connected to the displacement means and/or the solar cell for storing electrical energy. 
     Alternatively, the indication means may be arranged so as to be able to rotate freely and the displacement means may comprise an eccentrically positioned ballast. The specific positioning of the ballast achieves an oscillating effect, as a result of which the cleaning elements will swish in different directions. 
    
    
     
       The traffic device according to the invention will be described below in further detail with reference to the embodiments illustrated in the figures, in which; 
         FIG. 1A  shows a diagrammatic perspective view of an embodiment of the traffic device according to the invention, 
         FIG. 1B  shows a diagrammatic front view of an enlarged part of the traffic device from  FIG. 1A , 
         FIG. 2A  shows a diagrammatic front view of a next embodiment of the traffic device according to the invention, 
         FIG. 2B  shows a diagrammatic cross-sectional view of the traffic device from  FIG. 2A , 
         FIG. 3A  shows a diagrammatic front view of another embodiment of the traffic device according to the invention and 
         FIG. 3B  shows a diagrammatic cross-sectional view of the traffic device from  FIG. 3A . 
     
    
    
       FIG. 1  shows a perspective view of an embodiment of the traffic device (a roadside post) according to the invention. The roadside post  1  is in its position of use, namely the roadside  30  of a road  31 . The roadside post is provided with indication means  3  having a visible area  2  and with a cleaning device  4  for cleaning the indication means  3 . The cleaning device  4  has a plurality of cleaning elements  5 . Each cleaning element  5  has an elongate and flexible body  6  which is attached to the traffic device  1  at one end  20  and from there extends freely. The body  6  of the cleaning elements  5  in each case extends along the visible area  2  in such a manner that the body  6  can swish across the visible area  1  with its length for cleaning it. Some of the cleaning elements  5  are connected to one another at their attached ends  20  by means of a connecting part  18  which is adhesively connected to the roadside post  1 . The cleaning elements  5  are flexible to such a degree and have a length which is such that a swishing action is brought about by the air displacement of a vehicle passing at a distance of 5 metres at a speed of at least 50 km/hour. Due to the air displacement, the cleaning elements  5  will perform a swishing movement such as diagrammatically indicated by arrow  22 . During the swishing action, a high-energy contact is achieved between the cleaning elements  5  and the visible area  2 , with the cleaning elements  5  touching the visible area  2  at a variable pressure. 
       FIGS. 2A  and B show a front view and cross section, respectively, of a next embodiment of the traffic device according to the invention. The roadside post I′ has a circular indication means  3 ′ with a centre  10 ′ and an outer circumference  11 ′. For the sake of clarity, only a small number of bodies  6 ′ of the cleaning elements  5 ′ has been illustrated in the drawings. The visible area  2 ′ has projections  9 ′ which project from the visible area  2 ′ in such a manner that the projections  9 ′ touch the cleaning elements  5 ′ during relative displacement between the visible area  2 ′ and the cleaning elements  5 ′. The cleaning device  4 ′ has an outer ring  12 ′which is positioned coaxially with respect to the circular indication means  3 ′, which outer ring  12 ′ has a larger diameter than the circular indication means  3 ′. The cleaning elements  5 ′ extend radially. Some of the cleaning elements  5 ′ are attached by their attached ends  20 ′ near the centre  10 ′ and some of the cleaning elements  5 ′ are attached near the outer circumference  11 ′ and to the outer ring  12 ′. The outer ring  12 ′ is arranged so as to be rotatable with respect to the indication means  3 ′ about shaft  26 ′. The indication means  3 ′ is secured in a fixed position. The roadside post  1 ′ has a continuous air duct  13 ′ and the displacement means  8 ′ comprise a rotor  7 ′, the rotor  7 ′ being designed to be driven by the air flowing through the air duct  13 ′. The displacement means  8 ′ have first vanes  14 ′ provided in the outer ring  12 ′ in order to make the outer ring  12 ′ rotate, as is indicated by arrow  23 ′. The direction of air flow which is optimum for the operation of the traffic device  1 ′ is indicated by arrow  24 ′. 
       FIGS. 3A  and B show a front view and cross section, respectively, of another embodiment of the traffic device according to the invention. The roadside post  1 ″ has a cleaning device  4 ″ and a circular indication means  3 ″ having a centre  10 ″ and an outer circumference  11 ″. For the sake of clarity, only a small number of bodies  6 ″ of the cleaning elements  5 ″ have been shown in the drawings. The visible area  2 ″ has projections  9 ″ which project from the visible area  2 ″ in such a manner that the projections  9 ′ touch the cleaning elements  5 ″ during relative displacement of the visible area  2 ″ and the cleaning elements  5 ″. 
     The cleaning elements  5 ″ extend radially. Some of the cleaning elements  5 ″ are attached by their attached ends  20 ″ near the centre  10 ″ and some of the cleaning elements  5 ″ are attached to the roadside post  1 ″ near the outer circumference  11 ″. 
     The roadside post  1 ″ has a continuous air duct  13 ″ and the displacement means  8 ″ have a rotor  7 ″ in the form of a second vane  15 ″ situated in the air duct  13 ″. The second vane  15 ″ rotates in the direction indicated by the arrow  25 ″ through the air flowing through the air duct  13 ″ The second vane  15 ″ is connected to the shaft  26 ″ in such a manner that the indication means  3 ″ secured to the shaft rotates in the direction of arrow  23 ″. The direction of the optimum air flow for operation of the traffic device  1 ″ is indicated by arrow  24 . 
     It will be clear to the person skilled in the art that many variants of the traffic device according to the invention are conceivable without departing from the scope of protection defined in the claims.