SPREADING ARRANGEMENT
The invention relates to a spreading arrangement, designed for the prevention of slipperiness on roads, streets, highways and other areas, which arrangement uses an apparatus that has been mounted to a vehicle, according to the preamble of the independent claim 1.
A known method for prevention of slipperiness, in addition to mechanical and chemical means, involves the installation of heating devices under surfaces to melt streets or the like, or to keep streets or the like melted. Spreading sand on streets is the traditional method for the prevention of slipperiness, but in many cases, the effect of this measure is short-lived, or otherwise inadequate. Sanding is also an unsatisfactory method, because the vehicles project sand into the air, whereby the paint finish on other vehicles in the immediate vicinity may be hit by pebbles, or other damages may occur. Adding salt to the sand generally increases the effectiveness of the sanding, but addition of salt on the surface of roads only melts the ice if the temperature is not too low. However, there are many adverse effects which accompany salting, which have given rise recently to the use of salt liquid solutions, that is, a mixture of water and salt, which is spread to prevent slipperiness. Thus, the amount of salt per kilometre of road is lesser and the reduction in slipperiness is still very good. So-called wet salt has also been developed, which sticks to a road better than dry granular salt. Granular substances may fall to the side of the road soon after they have been spread as a result of traffic, whereby the substance's effect on prevention of slipperiness may remain minimal.
Many patent publications are known, wherein solutions for prevention of slipperiness are presented. US 6,173,904 presents an apparatus which is mounted to a vehicle and which comprises a storage space for salt or sand, with a disc spreader, as well as a liquid solution tank, from which the liquid for prevention of slipperiness is lead to a bar-like spray spreader low in the rear of the vehicle by a pump. The publication presents, in particular, the application of the apparatus in cases where the spread-width varies while the vehicle is in motion. The simultaneous spreading of more than one substance for prevention of slipperiness is presented as one of the alternatives of this apparatus, since, in addition to a barlike spray spreader, its spreading devices also include a disc spreader. However, there is no mention of alternating substances for prevention of slipperiness for environmental reasons and/or for damages caused to structures by the substances for prevention of slipperiness. In publication DE 41 09 366, a method is presented, whereby several substances for prevention of slipperiness, which are transportable in a vehicle, can be spread using several disc spreaders, particularly for prevention of slipperiness at airports and other corresponding areas. Each substance has its own disc spreader, which raises manufacturing costs of the device. Since there are usually three parallel spreaders, the spread-widths are also interlaced, which is often a disadvantageous spreading configuration.
Publication US 5,318,226 presents a spreading device which projects a very narrow wedge-shaped spray a long way rearward behind the vehicle. Publication EP 675 321 presents preparation of a salt paste by means of a grinding device in connection of addition of water and spreading of the paste onto the street by means of a disc spreader. Publication DE 1 534 292 presents mixing of table salt and liquid in an apparatus for prevention of slipperiness during spreading. The German publication 2124416 presents an apparatus, which comprises three dry-material tanks, two gear conveyors, water and oil tanks and a disc spreader, which is preceded by a separate mixing chamber and with damper. The mixture is carried along a pipe to the spreader device. This solution is complicated and expensive.
Spreading salt (most commonly sodium or calcium chloride) on roads, streets, highways, or other areas, in granular form or in a water solution, however, often gives rise to significant disadvantages. Vehicles rust quickly and become dirty due to salt and accumulate pitch on paved roadways. In groundwater areas, there is a great risk that harmful amounts of the contaminating substances for prevention of slipperiness will end up in the groundwater. Repairing the damages is practically impossible. The situation may remain detrimental for decades, if not centuries. Bridges, which are most commonly made of concrete and/or steel, will disintegrate or rust, which shortens intervals between restorations generally by many years bringing about great additional costs in road maintenance and the resulting road work causes a hindrance to traffic. Salt is also carried on the soles of shoes into buildings, which is an annoyance and creates a need for additional cleaning work. A substance for prevention of slipperiness with the trade name MELTIUM is available, which is suitable for use both in groundwater areas and with structures vulnerable to corrosion, such as bridges and tunnels, because its detrimental effects are lesser than the said conventional substances for prevention of slipperiness. The said relatively new substance is, however, exceedingly expensive compared to conventional substances for prevention of slipperiness, thus it is essential to treat only certain locations with it or with a corresponding substance, only in certain places, and to use the conventional substances elsewhere. An object of the invention is to provide a spreading arrangement to be used in prevention of slipperiness, the use of which will either reduce or eliminate all together the previously mentioned drawbacks and disadvantages. The object of the invention is to be able to use in a controlled manner only those substances for prevention of slipperiness, which are not at all as harmful as sodium or calcium chloride, in locations in which the use of salt is particularly harmful or damaging. The object of the invention is also to provide an arrangement by means of which the spreading of the harmful substance for prevention of slipperiness can be stopped very quickly and at a certain point on the road while the vehicle used in the prevention of slipperiness is in motion, and, if necessary, the spreading of some other substance for prevention of slipperiness having less harmful effects can be started. A further object of the invention is to provide an arrangement, whereby a mixture of two or more substances for prevention of slipperiness can be used. Additionally, an object of the invention is to provide a solution, whereby all transported substances for prevention of slipperiness can be spread effectively simultaneously, two together, or alternately, advantageously by using only one disc spreader.
The object of the invention is accomplished as described in the independent claim 1 and in the other claims. In the spreading arrangement according to the invention, an apparatus, which is mounted to a vehicle is used in prevention of slipperiness on roads, streets, highways and other areas, which apparatus comprises at least a dry- material tank for storing a granular or powdered substance for prevention of slipperiness, a liquid tank for storing a salt-water solution, which is used as a substance for prevention of slipperiness, and additionally, at least one liquid tank for a liquid substance for prevention of slipperiness to be used in specific locations, conveying means for conveying the substances for prevention of slipperiness from the said storage tanks to the disc-like spraying device, and control means for portioning of the said substances. If, when using a spreading arrangement, it can be selected by using control means at least whether to use only the substance for prevention of slipperiness from the said dry-material tank, spreading it with the said spraying device, or to use only the substance for prevention of slipperiness from the said salt-water solution tank, spreading it with the said spraying device, or to use a combination of these previously mentioned, i.e. liquid from the said salt-water solution tank for moistening the substance from the said dry-material tank, the moistening being carried out in the said spraying device prior to spreading, or to use the said liquid substance for prevention of slipperiness to be used for specific locations instead of the two above-mentioned substances which is spread in the specific locations by means of the said spraying device, then a versatile and modern vehicle-mountable arrangement for prevention of slipperiness is obtained. Even if the driving speed is over 60 km/h, the operator can, while the vehicle is in motion and without reducing the speed, stop the spreading of the material being used till then at a certain point on the road and begin the spreading of a new material. An experienced operator can change the material at to be spread very precisely at a certain point. In the vicinity of groundwater areas, the changing point is not very distinct, but exact selection of the changing point is an especially desirable characteristic, particularly concerning bridges, tunnels and other special locations. Thus, the invention enables such a precise prevention in prevention of slipperiness that places which are likely to have harmful or damaging consequences, especially of substances for prevention of slipperiness containing sodium or calcium chloride, can be treated with a substance for prevention of slipperiness that has less harmful effects on the environment and or on structures .
If the said selection can be made by means of the said control means while the vehicle is in motion, the measures for prevention of slipperiness are carried out quickly, and, at the same time, the vehicle can also quickly cover large sections of public roads.
If the operator of the vehicle selects by means of the control means to select the substance for prevention of slipperiness to be spread, or a combination thereof and portioning, the arrangement becomes quite reliable and the operator does not spend a lot of time or concentration on this work.
If the spreading arrangement comprises a GPS positioning device and a computer equipment whereto data concerning what substance for prevention of slipperiness is to be used in which spreading point and the corresponding portioning is saved, the operator of the vehicle can concentrate better on mere driving, which is particularly good from the point of view of traffic safety.
If the arrangement comprises a memory, where data concerning the route and prevention of slipperiness is saved, the data can be used in planning improvements to the arrangement. The data can, of course, also be used when investigating for example accidents, the working conditions of road maintenance personnel, the employment of time of the personnel at work and the effectiveness of the equipment, etc. If only one spreader is used as a spreading device, the disc of which spreader has an adjustable rotating speed, then the spread- width of the substance for prevention of slipperiness can be adjusted. By using a wide spread- width in certain cases, one spreading run can be saved if the road in question is considerably wide. Since only one disc spreader is used, and no bar spreaders equipped with several nozzles are used, a very simple structure with especially low manufacturing costs can be obtained. The solution is simple and therefore very reliable in operation, and also inexpensive to manufacture. Also, the likelihood of the system's malfunction is small in comparison to other solutions.
If magnetic valves, which serve as shut-off valves located before the liquid solution pump in the solution lines, the pump feeding the selected solution to the disc spreader, are used in selection of liquid substances for prevention of slipperiness, a structure can be obtained, in which the solution line can be opened or closed very quickly, i.e. in a fraction of a second. Thus, the interface between the start and finish of the spreading of the substance for prevention of slipperiness can be precisely defined.
It is recommended that the arrangement comprises an automatic apparatus, which takes into account the speed of the vehicle in portioning of the substance for prevention of slipperiness. Thus, the portioning of the substance for prevention of slipperiness is carried out quite easily to what is desired, regardless of the speed of the vehicle.
If the arrangement comprises an automatic apparatus, which controls the rotating speed of the disc spreader, according to what is defined as suitable for each substance for prevention of slipperiness or mixture of substances in the prevailing or anticipated road and weather conditions and in the speed used, it is easy to define the desired values, which have through testing been proven good for each substance for prevention of slipperiness in each situation.
If the arrangement comprises a feeder pump of the liquid substance for prevention of slipperiness, which pumps the solution from the tank to the spreader, while simultaneously a measuring device on the feeder pump is measuring the amount pumped, both the pumping and measuring the amount pumped can be carried out with the same device. Additionally, it is recommended that there be only one pump, whereby the structure is simple and, at that same time, inexpensive in manufacturing costs. If the feeder pump is also used in filling the tanks with substances for prevention of slipperiness at the base station of the vehicle or from a corresponding storage tank, liquid container or other receptacle, the same pump can be used in a very versatile manner and no other separate pumping equipments are required.
The invention will be described below in more detail with reference to the appended drawing, in which
- Figure 1 schematically illustrates a vehicle to used for prevention of slipperiness with its apparatus and arrangement
- Figure 2 schematically illustrates an installation diagram of an arrangement for prevention of slipperiness according to figure 1 with its devices and connections.
In the figure 1 of the drawing, reference numeral 1 indicates the vehicle, which is usually a heavy, three-axle truck. A snowplow 2 is mounted to the front of the truck 1. The apparatus for prevention of slipperiness 3 is either on the bed of the truck 1, or alternatively a part of the so-called traveling platform structure. Usually, an open reservoir 4 is used, which can generally store 4-10 cubic meters of sand or salt, or a mixture of them, i.e. a granular substance, albeit nowadays the use of sand or a sand-salt mixture on main roads has all but been abandoned. Nowadays, sanding with a rear-spreader is only used on lightly traveled side roads. The bottom of the open reservoir 4 is usually V-shaped, so that the screw conveyor located in the center line of the bottom, shown in figure 2, would move the entire load to a spreader 5, which is generally disc-like and rotated by a hydraulic motor 6. Blades project the substance to be spread to the area where it is to be spread. Located on the lower section of each side of the open reservoir 4 there are several solution tanks 7, which are nowadays usually made of plastic. Figure 1 shows three solution tanks 7a, 7b and 7c. On the other side of the reservoir 4 there can of course be, say three more solution tanks. The capacity of each tank is generally 200 - 1500 liters, but other sizes can of course be used if necessary. The tanks can, of course, be even of different sizes regards each other. Solution mixtures and desired concentration ratios of different substances can also be used in the tanks. Another tank 7 (not shown), big in comparison to the side tanks, can also be used, for example a tank having a capacity of 2000 - 6000 liters, most suitably in the front part of the vehicle's truck bed or the like, if the consumption of a substance in some area of use is especially heavy by comparison to the other substances for prevention of slipperiness. Figure 2 illustrates a system according to the invention, in which two solution tanks are marked, 7a for salt-water solution, such as sodium or calcium chloride- water solutions, and 7b for MELTIUM solution for prevention of slipperiness. A magnetic valve 8a is connected to tank's 7a pipeline, through which the solution reaches a pump 9, which is operated by a hydraulic motor 10. The magnetic valve 8b is correspondingly connected to the pipeline of the tank 7b. It is recommended that the magnetic valves 8a and 8b be mounted immediately before the pump 9, so that operation would be precise, because the shut-off point is as close to the pump
9 as possible. Nowadays, only salt in granular form is generally used in the reservoir 4, which salt is then pushed by a screw conveyor 11, powered by a hydraulic motor 12, to fall into a shaft 13, which guides the grains to the spreader 5. The spreader can be of a single-disc structure, known as such, or of a two-layer structure, in which the granular material is lead, if desired, to a different level than the solution material. Both of these discs, however, are operated by one driving motor. The design of the blades as well as the speed of rotation of the motor 6 can be used to affect the spreading of the material. Reference numeral 14 indicates a group of hydraulic valves, which valves are used to control the hydraulic motors 6,
10 and 12. A hydraulic pump, known as such, which provides the hydraulic motors with driving power, is not shown, because a conventional hydraulic pump mounted to the vehicle and powered by the truck's motor is used. One alternative is to equip the apparatus with its own combustion engine (known as such, not shown), which uses a hydraulic pump, or with a so-called fifth wheel (not shown), which is lowered and pressed down to touch the road at the rear of the vehicle, and the hydraulic pump, arranged in connection with the fifth wheel, when rotating, provides the hydraulic motors of the apparatus with driving power.
Reference numeral 15 indicates a control and regulating apparatus, whereby the operator of the vehicle 1 performs the spreading of the substances for prevention of slipperiness in the planned way. The electronic apparatus comprises a screen 16 and selector switches, amount control selector switches and other control devices, which, for the sake of clarity, have not been shown here. From the control and regulating apparatus there are necessary drive current connections 17 to the hydraulic valves 14 and to the magnetic valves 8a and 8b, and meter connections 18 for the hydraulic motors 6, 10 and 12. There is a communications connection 19 for the GPS positioning devices and a communications connection 20 for the road data from the road conditions center and a data connection 21 for saving the data of the entire procedure. Generally, the operator of the vehicle 1 uses the spreading arrangement according to the invention by means of the control and regulating apparatus 15 while driving. The operator can see the procedure, that is, the data concerning the spreading of the material, on the screen 16. The operator can change the material being spread very quickly, in an instant, using the control and regulating devices. This is necessary when the vehicle approaches, for example, a bridge or the like, where the spreading of the conventional salt and/or salt solutions should be stopped and the spreading of a special substance should be started. A change occurring in the portioning due to a change in the speed of the vehicle, functions on the basis of the vehicle's speedometer. Because of a special need, the operator can also increase or reduce the portioning. Numerous other functions can also be added to the arrangement, for example, arrangements warning of the ending of spreading materials. The arrangement according to the invention can also be used so that data concerning road sections is pre-fed into the GPS system, especially data concerning those road sections which, due to structures or groundwater, are to be treated with the special solution. Thus, the only task left for the operator is to drive the route, while the apparatus automatically takes care of the selection and portioning of the prevention of slipperiness materials. The data obtained through the data connection can be stored i.a. for research purposes and to clarify how much of what material was used on which road section, when it was spread and what effect it had on nature, especially, on the groundwater and on traffic safety, occurrence of accidents and to feedback from the road users, etc.
Although there were several separate tanks on the sides of the truck bed area, they can be connected together with pipelines and valves, whereupon the desired function is achieved. For example, connecting three tanks together using a joined- receptacles principle, a structure is achieved whereby the tanks are emptied at the same pace and no separate pumps or other special solutions are necessary at all. In order to increase the independence and versatility of the unit for prevention of slipperiness, it is recommended that the pump of the arrangement be used at the base station or elsewhere also for filling the tanks from transport receptacles, such as barrels or canisters or liquid containers. In this case, the piping and valves are used so that the pump draws the liquid from receptacles at the filling location to the tanks 7, in the event that there is no better refueling system of the liquids at the filling location.
The invention is not limited to the enclosed embodiment but several adaptations of the invention are conceivable within the scope of the enclosed claims.