Device for reducing the driving resistance of a truck

Abstract

The invention relates to a device for reducing the driving resistance of a truck and the input of heat into the truck, in particular a truck with a cooling device, comprising at least one van body (1) with a longitudinal direction L, a vertical van body plane of symmetry which runs in the longitudinal direction, a front surface which runs normal to the longitudinal direction L, a rear surface which runs normal to the longitudinal direction L, and a roof surface (2). In order to achieve the aforementioned aims of the invention, a profiled frame (4) is mounted on the roof surface (2), said profiled frame being designed to hold a canvas (7) in a stretched manner above the roof surface (2) and at a distance thereto directly or via an intermediate profiled section. Embodiments of the invention relate to devices for guiding the head wind, back-ventilating the gap below / behind the canvas, and cooling the gap by means of evaporation, to the installation of PV elements on the canvas, and more.

Description

[0001] Device for reducing the driving resistance of a truck

[0002] The following story concerns a device for reducing the driving resistance of a truck and, at its core, the energy savings of such vehicles, namely trucks / semi-trailers and / or their trailers / semi-trailers, during operation. The story is limited to vehicles whose bodies are designed as, or have, "boxes." Unlike tarpaulins, boxes have stable, solid, rigid, self-supporting outer surfaces. Boxes are typically cuboid-shaped. Boxes usually consist of multi-layer panels constructed entirely or predominantly of plastic. They are often provided with or consist of a thermal insulation layer. Internal stiffening elements, often metallic, such as aluminum, may also be provided independently. Occasionally, however, boxes are also simply made of sheet metal, similar to containers.

[0003] In conjunction with the truck and its direction of travel (curves or reversing are not taken into account), this results in a longitudinal direction L, which, cum sana gralis, corresponds to the direction of travel F, but is of course equally valid in both directions. This allows us to define a vertical, longitudinal plane of symmetry of the box, which, of course, should be considered technically rather than mathematically. Furthermore, the front normal surface of the box, viewed in the direction of travel, is its front surface, and the rear normal surface is its rear surface.

[0004] During operation, while driving, suitcases exhibit air resistance due to various aerodynamic effects, which are essentially due to their cuboid shape, increasing fuel consumption while driving. However, changing the cuboid shape is virtually impossible due to manufacturing technology and the size and shape of the transport space.

[0005] During operation and downtime, thermal problems caused by solar radiation occur practically everywhere in the summer, and in many parts of the world year-round, especially when the cases are used for cooling purposes. The following are a number of technical suggestions that can significantly reduce or even eliminate these and other problems.

[0006] A first aspect, independent of the other aspects, concerns the roof surfaces of such cases

[0007] In recent years, the side walls of truck bodies, and particularly of box bodies, have increasingly been provided with information and advertising. This provides a dual benefit: a smooth and therefore roadworthy outer surface while generating advertising revenue for the haulier. Particularly interesting solutions include printed tarpaulins held a short distance from the body surface using stretcher frames. The reason for this is that tarpaulins are easier to print on than the body surface, making them easier and simpler to change, and also that the gap, even if only a few millimeters, provides a certain degree of thermal insulation for the body surface. This helps reduce refrigeration costs, particularly when transporting food, medicines, etc.Of course, the installation of tarpaulins does not change the fact that a box must be present, which ensures the full functionality of the vehicle even without tarpaulins.

[0008] Since the roof area of ​​trucks is generally not easily visible, it has not been taken into account in such equipment for trucks or boxes.

[0009] As already mentioned, the advertising elements for the side panels are usually printed on tarpaulins, and the tarpaulins are mounted on the walls of the case using a tarpaulin mount, usually called a tensioning frame system. Such tensioning frame systems are known, for example, from the applicant's EP 1 604 346 or EP 597 094, WO01 / 35382, US 2002 / 104245, EP 1 271 456, DE 10 033 243, or even US 6,250,002.

[0010] Double roofs on semi-trailers are known from US2018 / 0015967, US 2010 / 0043264, and JP 2018-103840, but for mechanical reasons, they are inherently arranged as load-bearing components and only ventilated from behind. US 2016 / 0214661 discloses a device for reducing the "dead bag" in the rear area of ​​a truck, and DE 20 2012 003 343 UI discloses the use of special, photovoltaic-acting tarpaulins on trucks.

[0011] The contents of all such publications are incorporated into this statement for jurisdictions where this is possible.

[0012] During installation, a predetermined mechanical (tensile) tension is applied to the tarpaulin to keep it flat and smooth, thus visually appealing for advertising. In accordance with legal regulations, these tension frame systems are designed to be extremely flat and, despite the mechanical, thermal, and chemical stresses encountered in harsh road traffic environments with exhaust fumes, salt, grit, etc., they are very robust. Numerous such tension frame systems are known in the prior art. They consist of several individual components and, in any case, feature a frame profile permanently mounted to the body. Apart from the aforementioned contribution to thermal insulation, the tarpaulin and tension frame do not fulfill any special practical, technical, or physical (whatever you might call it) function.

[0013] Now, as mentioned at the beginning, one of the aims of the story is to achieve the greatest possible energy savings during the operation of a suitcase, especially while driving.

[0014] According to the initial concept, this goal is achieved by utilizing the roof area of ​​the box by attaching a tarpaulin to it using a tensioning frame. This creates thermal insulation even on the surface of the box that is most exposed to sunlight, especially in summer.

[0015] More precisely, this provides a device for reducing the driving resistance of a truck and the heat input into a truck, in particular into a truck with a refrigeration system, with at least one box with a longitudinal direction, a vertical box symmetry plane running in the longitudinal direction, a front surface running normal to the longitudinal direction, a rear surface running normal to the longitudinal direction and a roof surface, wherein frame profiles, collectively also called tensioning frames, are mounted on the roof surface and are intended to hold a tarpaulin stretched at a distance above the roof surface, directly or via intermediate profiles.

[0016] In a first development, the tarpaulin is equipped with photovoltaic elements (PVEs). Unlike their predecessors, today's PVEs are mechanically robust, thin, and at least somewhat elastic (and thus flexible), allowing them to be glued flat to the tarpaulin. The gap between the trunk and the tarpaulin is available for cables, regardless of whether they are used for power (electricity) or signal transmission. The generated electricity can, for example, power a refrigeration unit. Preferably, an extra battery for the generated charge (energy) is housed at a suitable location in the vehicle or in the trunk.

[0017] In a second development, independent of the first, the airflow flows through the gap between the tarpaulin and the roof of the box. At least one opening is provided between the tarpaulin and the box at the front, upper, horizontal edge perpendicular to the direction of travel, corresponding to the longitudinal direction L, and the gap merges freely into the environment at the rear, horizontal edge. Openings can also be provided on the sides of the frame system. The airflow naturally flows in the opposite direction to the direction of travel, but generally also in the longitudinal direction L. This creates an injector system, usually with a strong negative pressure in the gap, which sucks the tarpaulin towards the roof. With appropriate dimensioning, a stable condition can be achieved over wide speed ranges.

[0018] This not only significantly reduces heat input from solar radiation, particularly in vehicles with a cooled interior, and improves the efficiency of the PVEs due to the cool surface, but also means that, particularly during idle times, the preferred extra batteries are able to supply the cooling unit with energy for a longer period than conventional state-of-the-art batteries, without the need for an on-board engine or similar to run.In a third, independent, further development, the frame profiles - as already mentioned, the profiles of the tensioning frame - which are fixedly, but optionally detachably, arranged on the box, and which are directly or indirectly connected to tarpaulin profiles, which in turn are fixedly (movably and ultimately detachably, but not detachably) connected to the tarpaulin, are designed in such a way that flaps are arranged along the edges of the box roof surface running parallel to the direction of travel (longitudinal direction L), to which the frame profiles are mounted. These flaps can be opened or do open when the truck is moving. This lateral elevation at the edge of the box roof, running in the longitudinal direction L, improves air flow along the roof of the box.In particular, this significantly reduces the lateral flow of air, especially in the area of ​​the rear end of the case, onto the vertical side walls, thus preventing the formation of a large, "dead" air pocket at the rear of the vehicle. This significantly reduces air resistance while driving.

[0019] These side flaps preferably have one or more hinges on the outer side, as seen from the roof of the case, to which a wing is hingedly attached, the free end of which is connected to a flexible film or the like, the other longitudinal end of which is in turn attached to the frame profile, but at a distance from the hinge and thus from the side edge. The wing and the film are designed to be at least substantially airtight, and the attachments to the frame profile are at least largely airtight. Thus, by applying excess pressure inside this elongated structure, the wing can be extended or folded out, and then protrudes substantially upwards, away from the roof, thus directing the airflow longitudinally to the rear of the case. When the excess pressure is released, the wing is folded down by one or more spring elements, with the film preferably being pulled under the wing and covered by it.

[0020] It should also be noted that the hinges running in the longitudinal direction L do not have to be "true", multi-part hinges; they can each be a mechanically weakened, relatively narrow section of a plastic surface, a so-called "pseudo-hinge", which extends along the entire length of the respective frame profile. The film is preferably designed to be flexible in order to be protected when folded under the comparatively rigid sash, which must withstand the dynamic air forces. This construction can also be compressed by a height restriction if there is resistance. The film can be connected to the longitudinal edge of the sash and / or the frame profile independently of one another by gluing, sealing, or if necessary, by a clamping strip or other means. With knowledge of the narrative, the expert has many options at his disposal.Ultimately, the foil can also be replaced by a stiffer element, a question that the expert can easily solve with knowledge of the narrative and the area of ​​application.

[0021] In one variant, the flap can be a single piece consisting of the wing and two or three relatively flexible sections, which are connected by pseudo-hinges, each of which may exert a type of preload toward the rest position of the individual sections. In the area of ​​the outer edge of the flap, where it is connected to the frame profile, it is preferably connected to the frame profile via a type of piping that is pushed into a suitable receptacle in the frame profile. By designing and coordinating the cross-sections of the piping and the receptacle, a torque can be applied to the wing via elastic deformation, forcing it into the folded position, the rest position.

[0022] In order to create the appropriate overpressure inside the flap during ferry operation, i.e. between the frame profile, wing and film, a guide device for the airstream is designed on the front end of the flap (as seen in the direction of travel), through which a large amount of it is directed into the interior of the flap. The creation of the overpressure is supported by a semi-permeable closure of the flap at the rear end of the flap (at the rear), as seen in the direction of travel. This creates a certain amount of back pressure when driving and facilitates the build-up of overpressure, but at low speeds or when the case is stationary, allows the air to escape from the interior of the flap and thus fold the wing into its rest position. Of course, the application of controlled overpressure using the vehicle's pneumatics is also possible, but this requires additional lines and control systems.

[0023] By attaching the tarpaulin to the PVEs using the tensioning frame system, it is also easy to remove them, for example in autumn, store them safely over the winter and only reinstall them in spring when the increasing sunlight promises to be beneficial.

[0024] For this purpose, the PVEs are preferably arranged at such a distance from each other that a zigzag fold of the tarpaulin from front to back is possible, thus enabling the formation of a stack without mechanically overloading the PVEs. Since a particular visual appearance is not required for this design, several short tarpaulins can also be arranged one behind the other in the longitudinal direction L, which greatly simplifies assembly / disassembly and storage. Bridging pieces from tarpaulin to tarpaulin can be used without any problem to direct the airflow.

[0025] It goes without saying that such a tarpaulin with PV elements, possibly in pieces, can also be usefully mounted on the side walls of a box, especially if the vehicle is used in sparsely populated areas where advertising is not effective.

[0026] A second aspect, independent of the others, concerns the tarpaulin mounted on the roof in winter and is explained in more detail below with reference to the drawing. It should be mentioned briefly here that by providing an elongated air hose located at least approximately centrally along the longitudinal direction L of the roof under the tarpaulin, the tarpaulin takes on a nearly gable roof shape when inflated, allowing snow, ice, and dirt to be removed more easily than from a flat or even sagging tarpaulin, thereby significantly increasing safety and making work noticeably easier. This can be combined with any of the other aspects.

[0027] A third aspect, independent of the other aspects, concerns the creation of rear ventilation in the gap between the outer surface of the box and the inside of the tarpaulin, not only on the roof surface but also, if necessary, on the side walls, thereby lowering the temperature of the box in these large areas and reducing the thermal load, leading to a noticeable reduction in the necessary cooling capacity. This can be combined with the other aspects, in particular with the fourth aspect, as required. When the vehicle is stationary, rear ventilation can be achieved or improved through suitable openings in the horizontal, upper and lower profiles. Independent of all other aspects, corresponding holes, preferably with eyelets for mechanical reinforcement, can be provided in the edge areas of the tarpaulin(s), including those on the roof.

[0028] A fourth aspect, independent of the other aspects, is also the creation of rear ventilation, but independent of the third aspect, by covering the corners of the tarpaulin with the cover plates required for the tensioning frame system, either on their own or in conjunction with the third and any of the other aspects. Slot-shaped inlet openings (or outlet openings) are provided in the cover plates, running diagonally to the tarpaulin surface and diagonally to the longitudinal direction L. These create a connection from the environment to the gap between the case and the tarpaulin, through which airflow is introduced into the gap. It is interesting to note that the suction effect at the rear edges due to the injector effect of the airflow is greater than the effect achieved by the supply air from the front.

[0029] A fifth aspect, independent of the other aspects, concerns further thermal improvements that can be specifically combined with safety-related measures. This involves providing openings in the frame profile or between the body and the frame profile for rear ventilation, and installing spray nozzles for evaporating cooling water in the gap between the body and the tarpaulin, which can be combined in any way with the measures from the other aspects.

[0030] A sixth, independent of the other aspects, concerns the air resistance which occurs during driving due to unfavourable flows at the rear of a suitcase in the area of ​​its rear, vertical edges and which is reduced by special guide surfaces in this area of ​​the vertically running part of the frame profile of the side walls or a rear surface frame.

[0031] A seventh aspect, independent of the other aspects, concerns the air resistance of the outer surface of the tarpaulin itself. This is noticeably reduced by riblets that are applied by embossing the tarpaulin or when printing on it. The various ideas and aspects, all of which can be combined with one another in pairs, in multiples, or entirely, are explained in more detail below with the aid of the drawing, which shows / shows: Fig. 1 an embodiment of a wing in the folded state, Fig. 2 a schematic section normal to the longitudinal direction L of Fig. 1, Fig. 3 a view similar to that of Fig. 1, but with the wing raised, Fig. 4 a purely schematic view of the rear, upper, right corner of a suitcase with the wing raised, Fig. 5 a purely schematic cross-section normal to the longitudinal direction L in the upper area of ​​a suitcase, Fig. 6 a purely schematic cross-section through the plane of symmetry in the upper area of ​​a suitcase, Fig.7 shows a purely schematic vertical section in the upper edge area of ​​a case with a wind catching device for the airstream, Figs. 8a and 8b show rear and front ventilation devices, respectively, Fig. 9 shows a cover for a corner of a tarpaulin in plan view, Fig. 10 shows a section along XX of Fig. 9, Fig. 11 shows a first variant of a side tarpaulin with a special tensioning frame in a schematic vertical section normal to the longitudinal direction L, Fig. 12 shows a second variant of a side tarpaulin with a special tensioning frame in a purely schematic, perspective view and Fig. 13 shows a purely schematic and greatly enlarged surface structure of a tarpaulin in a perspective view.

[0032] Fig. 1 shows an embodiment of the present disclosure with a wind deflector in the folded state, without the case on which the structure is ultimately to be mounted. The structure has a frame profile 4 that is intended to be attached to the roof surface of a case, the longitudinal direction L corresponding to the direction of travel or being arranged exactly opposite to the direction of travel, whichever way you want to view it. Furthermore, the tarpaulin 7 is visible, which is held by its piping 8 in a tarpaulin profile 5. This tarpaulin profile 5 is in turn suspended in an intermediate profile 6, which is mounted in the frame profile 4 together with a holding profile 9. In order to compensate for tolerances or thermal expansion, the frame profile 4 is provided with several holding strips into which the profiles 6, 9 can be suspended.Such systems are known in various embodiments for attaching tarpaulins to the side walls of suitcases and can also be used in various forms in connection with the disclosure; therefore, it is not necessary to describe several embodiments here; the person skilled in the art can easily make his or her selection with knowledge of the disclosure.

[0033] In Fig. 2, which shows a section normal to the longitudinal direction L, a case 1 with its roof surface 2 is also shown, and a PV element 10 according to the disclosure is mounted on the tarpaulin 7. It is also evident from the illustration that the frame profile 4 extends at least to just the lateral edge 3 of the case 1 in order to make the entire surface 2 usable for the attachment of PV elements 10.

[0034] Furthermore, Fig. 2 shows that a type of undercut groove is formed at the edge end 11 of the frame profile 4, into which a folded wind deflector element, referred to as deflector element 12 for short, with a thickened portion 13 is inserted. This deflector element 12 extends, in one piece or in pieces, preferably over the entire length of the case 1. The folded configuration of the deflector element 12 shown in Fig. 2 is achieved by its semi-rigid design, particularly of the outer web 14, and an elastic prestress with respect to the thickened portion 13.

[0035] If the guide element 12 is now "inflated", for example by the airstream and corresponding supply elements - a purely schematic representation of an embodiment is shown in Fig. 7 - it takes on the shape shown in Fig. 3. The inner webs 15, 16, which practically lie on top of one another in the resting state, fold open about a type of hinge 17, and the connection between the outer surface 14 and the inner web 16 protrudes noticeably upwards above the plane of the tarpaulin 7. The direction L, which corresponds to the direction of travel, now leads to the air flowing over the tarpaulin 7 and thus the PV elements 10 when the box is moving, and not flowing laterally over the edge 3 of the box and increasing the vehicle's air resistance. At the rear end of the guide element 12, a slightly flexible and only slightly air-permeable closing film is preferably provided to facilitate the inflation of the guide element 12.This creates a speed-dependent airflow duct, which can significantly reduce the vehicle's air resistance and, if PV elements 10 are mounted on the tarpaulin 7, these are cooled, thereby increasing their efficiency.

[0036] Fig. 4 shows the situation at the rear, upper right corner of a box 1, viewed in the direction of travel. The longitudinal direction L corresponding to the direction of travel is indicated, and the guide element 12 is shown in the raised state; the partial end closure is not shown separately. The piping 8 of the tarpaulin 7, running parallel and transverse to the longitudinal direction L, is indicated, and the corner elements 19, which cover the corners as in the prior art with side tarpaulins, are shown. The portal, the rear closure wall of the box, is indicated purely schematically at 18; this is where the doors are hinged and where any covers are attached.

[0037] On the vertically arranged frame profile 22, in accordance with aspect six, covers, clips 23, with guide bars 24 are arranged, which are elastically mounted by clipping onto the frame profile 22. Preferably, a plurality of identical clips are clipped on independently of one another; this ensures that they release without great effort in the event of a collision and prevent or minimize damage and injuries; continuous strips with a plurality of guide bars are of course conceivable. The guide bars 24 improve airflow in this critical area. The height of the guide bars, by which they protrude above the outer tarpaulin surface, is approximately up to 2 cm and must always be aligned with the applicable legal regulations. The preferred direction of the individual guide bars 24 can be easily determined with a few tests; a perfectly usable arrangement is shown.The shape of the individual guide webs 24 can be adapted to specific requirements by various roundings and also changes in thickness. These clips 23 can of course be used on their own or without combination with the guide elements 12. In accordance with aspect two, Fig. 5 shows a variant that can be used on its own or in combination with other suggestions and aspects, which can be used particularly advantageously when the tarpaulin 7 is not provided with PV elements, thus mainly in winter. Fig. 5 shows a schematic section normal to the longitudinal direction L in the upper area of ​​a box. An inflatable tube 20 is provided in the center of the surface 2 and running in the direction of the longitudinal direction L, which is controllably inflated by compressed air when the vehicle on which the box is mounted is started up in winter, so that the tarpaulin lifts up in the middle like a flat gable roof within the scope of its elasticity.Additionally (not shown), waste heat from the engine, and possibly also some or all of the exhaust gases, can be conveyed into the roof space 21 forming next to the hose 20. Heat can also be supplied by reversing the operation of the PVEs, melting any snow or ice that may be adhering to the roof and either being easily removed or falling off on its own within the first few meters of travel. Dirt can also be removed more easily with the hose 20 inflated than on a flat surface.

[0038] If PV elements 10 are mounted on the tarpaulin 7 at a distance from the vehicle's longitudinal center, they are not subject to any bending stress during inflation, the adhesive layer can withstand the stress due to elastic expansion, and it is also possible to activate this arrangement when such a tarpaulin 7 is used.

[0039] Fig. 6 shows a vertical section, purely schematically, in the area of ​​the hose 20. A supply line 25 from a compressed air source leads, preferably in the front area of ​​the case, by means of a passage 26 to the hose 20 and supplies it with compressed air if desired, whereby the tarpaulin 7 is raised.

[0040] Fig. 7 shows a vertical, purely schematic section through the upper, lateral, front area of ​​a box 2 with a windbreak device, abbreviated to windbreak 27. The windbreak 27 does not protrude (or not noticeably) above the highest surface areas of the box as a whole (including the profiles, the tarpaulin, the guide elements, etc.) in order not to complicate driving through passages, garages, etc. During travel, the wind (arrows W) is fed to a supply line 31 by guide vanes 28, 29, and 30, and thus reaches the front surface of the guide element 12, which thus unfolds. The lower guide vane 28 prevents downward flow, the rear guide vane 29 promotes the partial reversal of the flow direction and the front guide vane 30 ensures to a large extent the repulsion of dirt, rain, snow, etc., which due to inertia do not reach the open area of ​​the windbreak 27.

[0041] Regarding the use and installation of the PV elements, it should be said in general terms that, particularly for roof surfaces, it can be advantageous to cut the tarpaulin into sections in the lengthwise direction L, so that only one, two, or three transverse rows, depending on the dimensions of the PV elements 10, have to be removed at a time. This means that these tarpaulin strips, since they do not have to be rolled or folded for storage, but can be laid on top of one another. In either case, the cabling is designed to allow either folding or separation. It goes without saying that the cabling of the PV elements preferably runs beneath the tarpaulin 7 in the cavity between the surface 2 of the case 1 and the underside / inside of the tarpaulin 7.

[0042] Fig. 8 shows, in the sense of aspect three, a device for rear ventilation of a tarpaulin, regardless of whether it is on the top surface or a side surface of a suitcase. In a first form, a type of strip 42 (to avoid the overused word "profile") is applied to the suitcase, which has through openings 43 running transversely to its longitudinal extent. During assembly, the direction of the openings is aligned with the longitudinal direction L, thus achieving the best possible passage of the airflow, indicated by the arrows W. The openings 43 can be formed in the strip, or, as can be clearly seen from Fig. 8a (air outlet), the strip 42 has rake-like projections 44, by the application of which (gluing, etc.) to the suitcase 2, the openings 43 are formed.

[0043] Such air vents can also be provided on the sides of the roof, if necessary within the guide elements 12, which results in better ventilation than usual during periods of downtime when the vehicle is exposed to sunlight.

[0044] Figs. 9 and 10 show, in the sense of aspect four, in plan view and in section along the axis of symmetry 31', a corner element 19 (cover plate) which serves to cover the corners of the mounted tarpaulin 7. Elongated, scoop-shaped openings 32 are provided perpendicular to the axis of symmetry 31', which point away from the outer corner 32 but do not project outwards. The injector effect creates a particularly strong negative pressure at the rear corners, which promotes ventilation. This arrangement always "captures" a component of the airstream in the front area, and in the rear area, air escaping from the airstream is "sucked in" by the injector effect. This means that "fresh" air always reaches the gap between the case and the tarpaulin, even without further measures while driving.

[0045] Fig. 11 shows, according to a first variant of the fifth aspect of the disclosure, a vertical section normal to the longitudinal direction L. An upper frame profile 33 is fastened to the lateral surface 2 of a case 1. In addition to the usual piping mount for the piping 8 of a tarpaulin 7, said upper frame profile 33 has an LED strip 34 which is connected to the indicator device and, during operation, significantly improves the visibility of the case 1 and thus of the vehicle. Such an LED strip can of course also be provided in other frame profiles. Furthermore, independently of this, the profile 33 has at least one channel 35 through which water can be directed. Each of the existing channels 35 is provided with nozzles (not shown), which are preferably directed substantially obliquely downwards, and thus sprays the inner surface of the tarpaulin 7 with water during operation, the evaporation heat of which further contributes to the cooling of the case 1.The channels can be “activated” in sections using holes and plugs (not shown).

[0046] A combination with targeted rear ventilation to improve evaporation according to aspects three and / or four contributes particularly to cooling. The water supply is preferably located at the front end of the case (front end), where the various supply lines and cables, etc., are already located in the current state of the art. Condensate from one of the commonly available cooling systems is preferred as the water source, as it is reliably free of salts and minerals. An intermediate tank and / or other supply source can easily be provided by the specialist.

[0047] The lower part of the illustration shows a lower frame profile 36, which, in addition to the usual options for variable attachment of the tarpaulin 7, also features an LED strip 34, which can be powered and controlled in the same way as the upper LED strip, if necessary independently of it. The illustration shows the horizontal frame profiles 33, 36 in a reversed arrangement compared to the prior art, since the profile with the variable mount for the tarpaulin is usually the upper frame profile.

[0048] Fig. 12 shows a second variant of this fifth aspect, in which the channels 35 are separate components that are attached to the case, possibly on their own mounting strip. Two channels are indicated here in order to achieve the most even distribution of the water over the considerable length of the case. Of course, more than two or even just one channel 35 can be provided. At the end area, a curvature of the channels is indicated (these can also merge into a collecting channel there) if the water is to be supplied in the lower area of ​​the case. The downward-pointing black arrows indicate the spraying of the water from the nozzles (not shown in detail).

[0049] To illustrate the various options, the upper frame profile 33 is provided with an upper bracket 38 that extends to the roof surface of the case, thus increasing the strength of the assembly. The frame profile 33 also has an outward-facing shoulder 45, at the end of which is the piping mount for the piping 8 of the tarpaulin 7. This, with appropriate dimensions, creates the possibility for air from the gap between the case and the tarpaulin to flow upwards, past the channels 35 and to the vent openings 37 in the shoulder 45, where it can escape from the gap into the open air, as indicated by the arrows.

[0050] Air access occurs either via corner elements 19 or openings in the lower frame profile (not shown) in accordance with aspect three, or through eyelets in the lower area of ​​the tarpaulin 7.

[0051] In both cases, and also in other embodiments of this aspect, the combination of the LEDs with the truck's turn signal system is particularly advantageous. If the LEDs also flash when the turn signal is activated, this leads to a significantly better perception of the truck's turning maneuver for all other road users. The achievable temperature difference on the exterior of the box compared to an exterior wall without a tarpaulin and active cooling is up to 10°C.

[0052] Fig. 13 shows the seventh aspect of the explanation: In a purely schematic, perspective view, the outer surface 38 of a tarpaulin 7 is shown at an extreme magnification: numerous strips, so-called riblets 39, are formed approximately parallel to the longitudinal direction L. At least the majority of the valleys 41 formed by these riblets 39 are interrupted by transverse webs 40. The distance from riblet 39 to riblet 39 is between 100 μm and 1 mm; the height of the riblets 39, relative to the adjacent valleys 41, is between 50 μm and 300 μm, and the length between the transverse webs 40 is in the single-digit to low double-digit centimeter range.

[0053] This structure is manufactured either by an embossing process for the sheet 7 prior to the possible application of a print, or by the printing process itself; both are known in the prior art for elements of this size. It is clear to those skilled in the art that, due to the aforementioned manufacturing processes, Fig. 13 does not provide a view that faithfully reproduces the shape of the riblets, nor their course and arrangement, but can only serve as a basis for the description.

[0054] This design of the tarpaulin surface in combination with the other aspects mentioned regarding the wind deflector system can achieve a reduction of up to 6% in fuel consumption during continuous truck travel.

[0055] List of reference symbols:

[0056] 1. Case 26. Implementation

[0057] 2. Case surface 27. Windbreak element

[0058] 3. Case edge 28. Strip

[0059] 4. Frame profile 29. Opening

[0060] 5. Plan profile 30. Projection

[0061] 6. Intermediate profile 31. Supply line

[0062] 7. Plane 31 ' symmetry plane

[0063] 8. Piping 32. Hood

[0064] 9. Keder profile 33. Upper frame profile

[0065] 10. PV element 34. LED strip

[0066] 11. Edge end 35. Channel

[0067] 12. Wind deflector 36. Lower frame profile

[0068] 13. Thickening 37. Ventilation opening

[0069] 14. Outer surface 38. Outer surface

[0070] 15. Inner web 39. Riblet

[0071] 16. Inner web 40. Cross web

[0072] 17. Hinge 41. Valley

[0073] 18. Rear surface, portal 42. Bar

[0074] 19. Corner elements 43. Opening

[0075] 20. Hose 44. Jump

[0076] 21. Attic 45. Shoulder

[0077] 22. Vertical frame profile L longitudinal direction

[0078] 23. Cover W Wind direction

[0079] 24. Guide bridge

[0080] 25. Supply line

Claims

Patent claims:

1. Device for reducing the driving resistance of a truck and the heat input into the truck, in particular a truck with a cooling device, with at least one box (1) with a longitudinal direction L, a vertical box symmetry plane running in the longitudinal direction, a front surface running normal to the longitudinal direction L, a rear surface running normal to the longitudinal direction L and a roof surface (2), characterized in that frame profiles (4) are mounted on the box surface (2) directly or via intermediate profiles, which frame profiles are intended to hold a tarpaulin (7) taut at a distance above the roof surface (2).

2. Device according to claim 1, characterized in that a wind deflector element (12) is fastened to the parts of the frame profiles (4) running in the longitudinal direction L, which wind deflector element (12) is raised higher than in the rest position above the roof surface (2) when the truck is traveling under the effect of the wind.

3. Device according to claim 2, characterized in that the wind deflector element (12) has an outer surface (14) which is rotatably articulated on the frame profile (4) with one of its longitudinal sides, and that the other longitudinal side is connected to the frame profile with inner webs (15, 16) with its longitudinal side facing away from the outer surface (14) in a flexible manner, preferably via hinges or pseudo-hinges.

4. Device according to one of claims 1 to 3, characterized in that a wind catcher element (27) is arranged on the end face of the case (1), which directs the airstream to a supply line (31) by means of strips, projections and openings (28, 29, 30), that the supply line (31) is fluidically connected to the end face of the wind deflector element (12), and that preferably the rear end of the wind deflector element (12) is partially fluid-tight.

5. Device according to one of the preceding claims, characterized in that photovoltaic elements (PVEs) (10) are attached to the outside of the tarpaulin (7).

6. Device according to one of the preceding claims, characterized in that between the roof surface (2) and the tarpaulin (7) at least approximately in the plane of symmetry of the case a hose (20) is arranged in the longitudinal direction L, which is connected to a compressed air source and to an adjustable release valve, wherein in the unpressurized state of the hose (20) the tarpaulin (7) runs essentially flat and in the pressurized state of the hose (20) the tarpaulin (7) takes on the shape of a flat gable roof.

7. Device according to claim 6, characterized in that in the pressurized state of the hose (20) the roof space (21) between the tarpaulin (7) and the roof surface (2) and / or the tarpaulin (7) itself can be heated, for example by reverse operation of the PVEs (10), and / or by blowing exhaust gas into the roof space (21) and / or by external energy.

8. Device according to one of the preceding claims, characterized in that at least the frame profile (4) mounted on the front surface and the rear side of the case (1), on the roof surface (2) or on the side walls has openings (43) or forms them in connection with the case, through which the airstream (W) flows into the gap between the case (1) and the tarpaulin (7).

9. Device according to one of claims 1 to 7, characterized in that at least the frame profile (4) mounted on the front surface and the rear side of the case (1), on the roof surface (2) or on the side walls is mounted on a profile which has openings (43) or forms them in connection with the case and / or the frame profile, through which the airstream (W) flows into the gap between the case (1) and the tarpaulin (7).

10. Device according to one of the preceding claims, characterized in that on the side surfaces of the case (1) in the upper frame profile (33) in the gap between the case (1) and the tarpaulin (4), at least one channel (35) with nozzles is formed, which are intended to spray water into the gap.

11. Device according to one of the preceding claims, characterized in that an LED strip (34) is mounted in the upper and / or lower frame profile (33), which is preferably operatively connected to the indicator device of the truck.

12. Device according to one of the preceding claims, characterized in that profile-covering corner elements (19) with a plane of symmetry (31') are provided at the corners of the clamping frame formed by the profiles, which have scoops (32) which run on the corner element (19) normal to the plane of symmetry (31') and are intended to deflect airflow at the front corners of the case (1) into to direct the gap between the case (1) and the tarpaulin (7) and to suck air from this gap into the environment at the rear corners by means of the injector effect.

13. Device according to one of the preceding claims, characterized in that the outer sides of the tarpaulins (7) on the roof surface (2) and / or on the side surfaces are provided with a riblet structure (39) which is intended to reduce the air resistance during travel.

14. Device according to claim 13, characterized in that the distance from the elongated riblet (39) to the adjacent riblet (39) is between 100 μm and 1 mm; that the height of the riblets (39), relative to the adjacent valleys (41), is between 50 μm and 300 μm; and that the length of the valleys (41) between the transverse webs (40) running from riblet (39) to riblet (39) is in the single-digit to low double-digit centimeter range.

15. Device according to one of the preceding claims, characterized in that covers (23) are clipped onto the rear, vertical frame profiles (22) of the case (1), which have guide webs (24) which guide the Improve the wind in this critical rear area.

Images