Abstract
The present invention concerns an improved flow control device for a vehicle (1), especially for a truck or small van, that comprises at least one air deflector blade (10, 12), which can be installed in an operating position as an extension of the contour on a rear vehicle edge (52), which forms an air deflector area and which is installed tiltably around a swivel axis by means of an adjustment unit between the operating position (I) and a stowing position (II). The present invention further concerns a vehicle (1) that is equipped with the flow control device.
Claims
1. Flow control device for a truck, that comprises at least one air deflector blade (10, 12) that can be arranged in an operating position as a contour extension on a rear truck end (52), that forms an air deflector area and that is installed in a way as to be flexibly tiltable around a swivel axis by means of an adjustment unit between the operating position (I) and a stowing position (II), wherein the air deflector blade (10, 12) comprises at least one air deflector element (14, 18) and at least one flexible sliding element (16, 20) that can be moved translationally in relation to the air deflector element (14, 18) in parallel to the swivel axis and is installed on the air deflector element (14, 18); and wherein the at least one air deflector blade comprises two lateral air deflector blades (10) for flow control on opposite lateral areas (4) of the truck (1) and one top-side air deflector blade (12) for flow control on a roof area (2) of the truck (1), whereby each lateral air deflector blade (10) comprises an air deflector element (18) and a flexible sliding element (20), whereby the top-side air deflector blade (12) comprises two air deflector elements (14) and two sliding elements (16) and the flexible sliding element (20) of each lateral air deflector blade (10) is adjacent to a sliding element (16) of the top-side air deflector blade (12) in the operating position (I) to form a corner area of the flow control device.
2. Flow control device according to claim 1, wherein at least one of the air deflector blades (10) can be lifted by means of a swivel axis body (70), which is enclosed by a sleeve (74) equipped with a helical groove (72) that is penetrated by a joint rod (42) connected to the swivel axis body (70) and the respective air deflector blade (10).
3. Flow control device for a truck, that comprises at least one air deflector blade (10, 12) that can be arranged in an operating position as a contour extension on a rear truck end (52), that forms an air deflector area and that is installed in a way as to be flexibly tiltable around a swivel axis by means of an adjustment unit between the operating position (I) and a stowing position (II), wherein the air deflector blade (10, 12) comprises at least one air deflector element (14, 18) and at least one flexible sliding element (16, 20) that can be moved translationally in relation to the air deflector element (14, 18) in parallel to the swivel axis, wherein sliding elements (16, 20) that are adjacent to each other form a corner area (22) in the operating position (I) and wherein adjacent air deflector blades are mechanically coupled to each other at their non-attached end in the corner area.
4. Flow control device for a truck (1) according to claim 3, wherein the air deflector blade (10, 12) comprises a top-side air deflector blade (12) which is divided by and symmetric to a central longitudinal axis (62).
5. Flow control device for a truck (1) according to claim 3, further comprising at least one assembly plate (54) on which the air deflector blade (10, 12) is installed tiltably and with an actuator.
6. Flow control device for a truck, that comprises at least one air deflector blade (10, 12) that can be arranged in an operating position as a contour extension on a rear truck end (52), that forms an air deflector area and that is installed in a way as to be flexibly tiltable around a swivel axis by means of an adjustment unit between the operating position (I) and a stowing position (II), wherein the air deflector blade (10, 12) has an outer area (32) which forms, in a cross-section view, a tangent on a longitudinal edge (LE) of a rectangle (R) at a front edge (36) of the air deflector blade (10, 12) and which is located in a corner point of the longitudinal edge (LE) with a transversal edge (TRE) of the rectangle (R) in whose opposite corner point there is a rear edge (44) of the air deflector blade (10, 12), whereby the outer area (32) between the front edge and the rear edge (36, 44) is convex curved and whereby the longitudinal edge (LE) of the rectangle (R) has a length (L) of between 350 and 700 mm, and whereby the transversal edge (TRE) has a feed length (F) of between 0.2 and 0.3 of the length (L) of the longitudinal edge (LE) and further comprising an indentation (ID) extending away in a linear rear edge section (RES), which is installed in an upper area of a lateral air deflector blade (10).
7. Flow control device for a truck (1) according to claim 6, comprising a top-side air deflector blade (12) with a trough (TR) that is symmetric to a central longitudinal axis (62) in the operating position (I) and that is formed as a recess in relation to linear lateral sections (LS) of a rear edge (44) of the top-side air deflector blade (12).
8. Flow control device for a truck (1) according to claim 6, wherein the lateral air deflector blade (10) in the operating position (I) has a height of between 1,200 and 2,700 mm.
9. Flow control device for a truck (1) according to claim 6, wherein the indentation (ID) is limited on both sides by segments of the linear rear edge section (RES.sub.1, RES.sub.2).
10. Flow control device for a truck (1) according to claim 9, wherein an upper end (UEID) of the indentation (ID) with a distance of between 200 and 300 mm from a top edge (TE) of the lateral air deflector blade (10) extends away from the linear rear edge section (RES) and/or extends away from the linear rear edge section (RES) with a lower end (LEID) at a distance of between 500 and 600 mm from the top edge (TE).
11. Flow control device for a truck (1) according to claim 6, wherein an upper edge (UE) of the lateral air deflector blade (10) is formed by a convex curved feed that is retracted downward and that levels off with a <5° angle in relation to the horizontal plane.
12. Flow control device for a truck (1) according to claim 7, wherein the trough (TR) extends with a lateral distance (LD) of between 0.2 and 0.3, of a width (W) of the top-side air deflector blade (12), from the linear lateral sections (LS).
13. Flow control device for a truck (1) according to claim 12 wherein the trough (TR) has a trough depth ([D]) of between 0.15 and 0.25 of the length (L).
14. Flow control device for a truck (1) according to claim 7, wherein a lateral contour (LAC) of the top-side air deflector blade (12) is formed by a convex curved feed that is retracted to the inside and that levels off with an angle of <5° towards a parallel line of the central longitudinal axis (62).
15. Flow control device for a truck (1) according to claim 7, wherein movement of the lateral air deflector blade (10) is mechanically coupled with movement of the top-side air deflector blade (12).
16. Flow control device for a truck (1) according to claim 6 wherein two lateral air deflector blades for flow control on opposite lateral areas (4) of the truck (1) are each formed as uniform air deflector blades (10) and that only an upper air deflector blade (12) for flow control on a roof area (2) of the truck (1) comprises an air deflector element as well as one flexible sliding element (16; 20) installed on the edge.
Description
(1) Further details and advantages of the present invention can be taken from the description in connection with the drawing. This drawing displays:
(2) FIG. 1 a side view of a design example of a vehicle with a design example of a flow control device;
(3) FIG. 2a a top view of the flow control device on the rear of a truck in the stowing position;
(4) FIG. 2b a side view of the design example shown in FIG. 2a;
(5) FIG. 3a a top view of the design example shown in FIGS. 2a and 2b in the operating position;
(6) FIG. 3b a side view of the design example shown in FIGS. 2a to 3a in the operating position;
(7) FIG. 4a to 4f side views in perspective of the design example shown in the FIGS. 2 and 3 regarding the movement pattern during the shift of the design example from the stowing position to the operating position;
(8) FIG. 5 a top view of an assembly plate of the previously described design example;
(9) FIG. 6 a top view of a structural module of the assembly blade;
(10) FIG. 7 a sectional view along the line VII-VII according to the display in FIG. 6;
(11) FIG. 7a a top view of a section of a vehicle when the door is swiveled open;
(12) FIG. 8 a cross-section view according to FIG. 7 in different phases of the swiveling movement from the stowing position to the operating position;
(13) FIG. 9a a schematic illustration to explain the geometry of the outer surface of the air deflector blade;
(14) FIG. 9b, 9c illustrations according to FIG. 9a to explain the modifications of the contour of the outer surface;
(15) FIG. 10 a side view of a lateral deflector blade in the operating position;
(16) FIG. 11 a top view of a design example of a top-side air deflector blade in the operating position;
(17) FIG. 12a a top view according to FIG. 10 with dimensioning lines whose values can be found in Table 12b;
(18) FIG. 13a a top view according to FIG. 11 with dimensioning lines whose values can be found in Table 13b;
(19) FIG. 14 a top view in perspective of a possible wire conduit between a lateral air deflector blade and a top air deflector blade;
(20) FIG. 15 a graph for a possible speed pattern while the vehicle is driving to explain an activation process of the air deflector blades; and
(21) FIG. 16 a side view in perspective of a partially upright lateral blade including a mechanism with a helical groove.
(22) FIG. 1 shows a side view of a design example on the example of a semi-trailer that forms a design example of a vehicle in the sense of the present invention and that has a box van enclosing a cargo space. The box van forms a roof area 2 as well as two longitudinal side areas 4 that are opposite to each other. A design example of a flow control device 8 extends away from a rear area 6 of the semi-trailer 1.
(23) Details of this flow control device 8 are explained in the FIG. 2a to 3b in the two settings, i.e. the stowing position (FIG. 2a, 2b) and the operating position (FIG. 3a, 3b).
(24) The design version has two vertically extending lateral air deflector blades 10 and a horizontally extending top air deflector blade 12 that is installed in between.
(25) The top air deflector blade 12 consists of four elements, i.e. two air deflector elements 14 that are flexibly hinged and two sliding elements 16 that are translationally flexible in relation to each other and in relation to the associated air deflector elements 14 in a horizontal direction.
(26) The lateral air deflector blades are formed of an air deflector element 18 and a respective longitudinally flexible sliding element 20. The sliding elements 20 are installed relocatably in the vertical dimension.
(27) In the stowing position shown in the FIGS. 2a and 3b, the air deflector elements 14 and/or 18 are bumping into each other in corner areas 22. A substantially U-shaped closed surface, that is made up by the outer surface 24 of the lateral and the outer surface 26 of the top air deflector blades, is formed.
(28) Through swiveling, the air deflector blades 10, 12 are set outward (FIG. 3a, 3b). As part of this swiveling movement, the air deflector blades 14, 18 are slewingly moved around hinge points, whereas the sliding elements 16, 20 are moved translationally alongside the swivel axes of the respective air deflector elements 14, 18. The swivel axes of the air deflector elements 18 of the lateral air deflector blades 10 thereby extend in the vertical dimension, i.e. in parallel to swivel axes of doors 28 of the semi-trailer 1 that are, in an ideal case, separated from each other in a vertical axis 30. The air deflector elements 14 of the top air deflector blade 12 are swiveled around the horizontal axis. Due to the sliding movement of the sliding elements 16 and/or 20, they bump against each other in the corner areas 22 in the operating position shown in FIGS. 3a and 3b. A U-shaped closed flow control area as an extension of the outer areas of the semi-trailer, i.e. the roof area 2 and the longitudinal side areas 4, is developed. Also in the operating position, a lower edge of the lateral air deflector blades 10 has a distance A, accordingly between 0% and 200% of the length of the lateral air deflector area in an upright position, from the lower edge of the rear area 6. As part of the swivel movement, the air deflector elements 14, 18 as well as the sliding elements 16, 20 are not only swiveled around their respective swivel axis, but also moved translationally outward. The kinematics is explained in FIG. 8.
(29) FIG. 8 shows an air deflector blade, for example a lateral air deflector blade 12, in a cross-section view. The air deflector blade 10 is designed as a closed hollow element which is limited by a convex curved outer surface 32 on the outside and by a linearly extending inner surface 34 on the inside. The outer surface 32 and the inner surface 34 taper off in their end areas. At a distance of approximately one third of the overall length L of the air deflector blade 10 from a front edge 36 of the air deflector blade 10 there is a first hinge point 38 on the blade, which is coupled with an outer hinge point 40 on the fixation unit through a front joint rod 42. In the area of the rear edge 44, there is a second hinge point 46 on the blade, which is connected through an inner hinge point 48 on the fixation unit whereby a rear joint rod 50 is interposed as a linking piece.
(30) This hinged installation of the air deflector blade 10 forms a design example of an articulation gear in this present document. The articulation gear is chosen in a way that the front edge 36 evenly nudges a rear vehicle edge 52 (presently the edge between the longitudinal side area 4 and the rear area 6—dotted lines) in an operating position marked with the reference sign I, whereby the outer surface 32 prolongs the longitudinal side area 4 in the area of the front edge 36 at first linearly in a tangential manner so that an air deflector area, that extends without interruptions from the rear vehicle edge 52 to the rear and that ends on the rear edge 44 in an inward-retracted position, forms on the outer surface 32 of the blade 10. In an intermediate position Z between the operating position I and a stowing position II, the air deflector blade 10 is already bent inwards. Due to the articulation gear, the front edge 36 is already lifted off the rear vehicle edge 52 towards the back and offset towards the inside. In the stowing position II, the linear inner surface 34 is substantially parallel to an assembly plate marked with the reference sign 54.
(31) Details of this assembly plate are displayed in the FIG. 5 to 7. FIG. 5 thereby illustrates the arrangement of the hinge points 48 and/or 40 on the fixation unit. As evident in FIG. 5, the assembly plate 54 is L-shaped and has appropriate hinge points 40, 48 on the fixation unit for the lateral deflector blade 10 and the top air deflector blade 12, that together form a L-shaped segment 56 (see FIG. 6). The respective hinge points 40, 48 on the fixation unit are each indicated identically for the top air deflector blade 12 and the lateral air deflector blade 10.
(32) As we can see in FIG. 6, the segment 56 consists of an air deflector element 14 and a sliding element 16. FIG. 6 shows a top view of the stowing position and illustrates, together with FIG. 7, the integration of the respective air deflector blades 10, 12 in a fitting case 58 which is limited by the assembly plate 54 at the bottom and laterally by the end caps 60, that have a convex curved contour and that all merge continuously and without interruption into the outer surface 32 of the associated air deflector blade 10, 12. As illustrated in FIG. 6, the end caps 60 move around the respective blades 10, 12 on the outside in the stowing position. The respective end caps are only missing on the vertical axis 30 because the left L-shaped segment 56 shown in FIG. 6, which is developed as a pre-assembled structural module and which can be attached to the vehicle, almost nudges onto the right segment that is also L-shaped but not shown in FIG. 6.
(33) Thanks to the described variant, an aesthetic look is created also in the stowing position. The linear inner surface 34 largely extends in parallel to the assembly plate 54. The elements 38 to 50 of the articulation gear are covered by the end caps 60 at the top and on the edges of the blade and are therefore essentially protected against dirt. FIG. 7a further shows that a door 28, that takes in the lateral air deflector blade 10 and the segment 56 of the top air deflector blade 12, can be set to an open position swiveled by approximately 260° from the closing position discussed so far without causing the air deflector blades 10, 12 to collide with the longitudinal side area 4 of the semi-trailer. The arrangement increases the thickness of the door 28 only insignificantly. The doors 28 can still be swiveled freely towards the outside without any impairment.
(34) FIG. 4a to 4f illustrate the setting of the air deflector blades 10, 12 from the stowing position II (FIG. 4a) already discussed before to the operating position I (FIG. 4f).
(35) In the stowing position according to FIG. 4a, the air deflector elements 14, 18 of the respective air deflector blades 10, 12 nudge against each other in the corner area 22. The sliding elements 16 and/or 20 are located on the associated air deflector elements 14, 18. Hence, each air deflector element 14 of the top air deflector blade 12 reaches beyond the associated sliding element in a horizontal extension, whereas the sliding element 20 of the lateral air deflector blade 10 is exceeded by the air deflector element 18 of the respective air deflector blade 10 on both sides. The swivel movement is triggered by actuators that are arranged within the fitting case 58 in the stowing position II. In this process, the sliding element is, on one hand, swiveled outward and moved translationally in the manner described above under reference to FIG. 8. On the other hand, the sliding elements 16 of the top air deflector element 12 are driven outwards whereas the sliding elements 20 of the two lateral air deflector blades 10 are moved upwards. In other words, the sliding elements 16, 20 approach each other while a swivel movement of the air deflector blade 10 and/or 12 as a whole is carried out. At the end of this swivel movement, the respective air deflector blades 10, 12 are in the operating position I. The sliding elements 16, 20 nudge against each other in the corner areas 22 and now exceed an upper boundary edge of the air deflector element 18 and/or a lateral boundary edge of the air deflector elements 14 that were essentially still adjacent to each other in the corner areas 22 in the stowing position before but that contribute in any case to a U-shaped, continuously developed contour in the stowing position (see FIG. 4a).
(36) FIG. 9a explains the design of the cross-sectional geometry of an air deflector blade 10, 12. It focuses particularly on the contour of the outer surface of the air deflector blade 10, 12. In the following, the described air deflector blade shall be a lateral air deflector blade. The respective description, however, could equally be used for the design and construction of the top-side air deflector blade 12.
(37) The air deflector blade 10 has a length of between 350 mm and 700 mm, preferably of between 400 mm and 600 mm. Length L shall mean the extension of a longitudinal edge LR of a rectangle R which is tangentially approached by the outer surface 32 in the area of the front edge 36. The front edge 36 is thereby located in that section, i.e. sectional and/or end point, of the rectangle R where the longitudinal edge LR intersects with a transversal edge QR. The two longitudinal edges LR and the two transversal edges QR span the rectangle R. The rear edge 44 of the air deflector blade 10 lies in an end point opposite to the corner point in which the front edge 36 is located. As already mentioned, the outer surface 32 between the two edges 36, 44 is continuously curved. The transversal edge QR has a feed length E of between 0.2 and 0.3, preferably of between 0.22 and 0.24 of the length L of the longitudinal edge LR. This flow geometry proves to be advantageous to guide the air on the rear of the vehicle. There is no need to say that the front edge 36 should be installed if possible in direct contact, i.e. without interruption, with the associated surface, i.e. the roof surface 2 and/or the longitudinal side area 4 of the vehicle. In other words, in one arrangement of the air deflector blade 10, the longitudinal edge LR prolongs the longitudinal extension of the associated area 2, 4 in the operating position. On this basis, the feed length E is the degree by which the air deflector blade 10 guides the flow to the inside and to the rear of the vehicle.
(38) The contour of the air deflector blade 10 shown in FIG. 9a can be modified experimentally when it appears that the flow drifts away prematurely from the outer surface 32. This can, for example, be caused by turbulences on the external mirrors of the towing vehicle. Practical experiments by the present inventors have shown that turbulences develop on the upper edge and on the lower edge of the lateral mirror of the towing vehicle behind the lateral mirror and on the longitudinal side surface 4 of the vehicle. In the process, the turbulence caused by the upper edge of the outside mirror usually turns towards a roof turbulence that exists on the corner between the longitudinal side area and the roof surface. Due to the spin of the two associated turbulences, there will be an area of decelerated flow in between, which can cause the flow to drift away prematurely from the contour shown in FIG. 9a. Such a drifting effect can be identified on the vehicle in an experiment under real flow conditions.
(39) The two abovementioned roof turbulences spin in opposite directions so that an area of decelerated flow also develops in the middle of the roof area. Also here, the flow rather tends to drift away from the top-side air deflector blade 12.
(40) The aerodynamic effect of the air deflector blade 10, 12 can now be improved by adapting the contour to the locally active flow conditions as illustrated in the FIGS. 9b and 9c. There, the blade shown in FIG. 9a is drawn into a rectangle R with dotted lines which is equivalent to the rectangle R according to FIG. 9a. A break-off point [PA] shall be the point at which the flow is observably drifting away under driving conditions (for example at a travel speed of 80 km/h). For the modification, there is further a distance [A] whose amount can be between 0.1 and 0.05 of the feed length F. The distance is greater than zero. The contour should now be modified in a way that the distance between the break-off point and the rear edge 44 locally has the length [A]. More precisely, the contour is adapted to trigger a defined amount of break-off into the shear layer in the sense of the “super-critical condition”. The degree of defined break-off shall be predefined by A.
(41) A possible correction is displayed in FIG. 9b. There, the length and the feed are adapted to the location of the break-off point while the curvature is maintained. The new feed length F′ and hence the modified transversal edge QR′ are formed by the distance between the longitudinal edge LR associated to the front edge 36 and the break-off point plus the distance [A]. The curvature of the original outer surface is not modified in the process and consequently there will also be a new length L′.
(42) The second correction possibility is shown in FIG. 9c. There, the feed is changed while the length L is kept constant, which changes the curvature of the contour changes and consequently influences the situation of the break-off point. A reduced curvature from an initial contour KU to a modified contour KM leads to a shift of the break-off point towards the rear edge 44. In other words, the situation of the break-off point is adapted to the contour length. The new feed length E″ and hence the modified transversal edge QR″ are formed by the distance between the longitudinal edge LR, that is associated to the front edge 36, and the break-off point plus the distance [A].
(43) In addition to the adaptation by means of one of the mentioned processes, a hybrid solution in which both the curvature and also the contour length are locally adapted is also possible. This way, the shape of the air deflector blades can be modified while maintaining the distance [A].
(44) The lateral air deflector blade 10 in the operating position has a height of between 1200 and 2700 mm, preferably of between 1800 and 2300 mm. As illustrated by FIG. 1, the air deflector blade 10 of the invention is less high than the continuous longitudinal side surface of the vehicle that is located in front of the air deflector blade. The height of the lateral air deflector blade 10 does usually not exceed 75%, preferably 60%, of the height of the associated longitudinal side surface 4. “Height” shall thereby mean the extension in the assembled state and in the operating position in the vertical plane. This height is indicated by H in FIG. 10, whereby this figure shows the operating mode. FIG. 10 also shows a convex curved lower contour which extends from the front edge 36 with an angle between 0° and 50°, preferably between 0° and 20° and especially preferably between 1° and 10°. In case of a tilt angle greater than 0°, the lower contour K is located within a rectangle which is defined by the length L discussed before and the height H. In other words, the area of the lower contour UK, that is close to the edge, is tilted upwards. The lower contour UK, however, substantially approaches the horizontal plane, that is situated mainly in parallel to the extension of the length L, in a tangential way. Furthermore, the upper part of the lower contour UK merges tangentially into a vertically linear rear edge section HKA. This rear edge section HKA extends in the vertical plane.
(45) In the illustrated design example of a lateral air deflector blade 10 according to FIG. 10, the rear edge section HKA extends in an interrupted manner from an indentation EB up to a point that has a distance from a top edge OKA of the air deflector blade 10 equivalent to the feed length E discussed before. The convex curved contour UK has a height extension AUK, whereby AUK indicates the distance dimension between the bottom UKA (intersection with front edge 36) and the top end of the lower contour UK, which amounts to approximately 500 to 900 mm, preferably of between 600 and 800 mm. This indicates the length of the linear rear edge section HKA including the indentation EB to (H-HUK-E). In the illustrated design example, the indentation EB is limited by segments HKAS.sub.1 and HKA.sub.2 of the rear edge section. The indentation EB is located in the upper area of the lateral air deflector blade 10. The center of the indentation is located approximately 400 mm above a top edge OKA of the air deflector blade 10. An upper end EBOE of the indentation has a distance of between 200 and 300 mm from a top edge OKA. At this top end EBOE, the indentation extends away from the upper segment HKA.sub.2 of the linear rear edge section HKA. A lower end EBUE of the indentation EB has a distance of between 500 and 600 mm from the top edge OKA and extends away from the lower segment HKA.sub.1 of the linear rear edge section HKA there. Where the setting was adjusted to the distance to the top edge OKA as mentioned above, this was ensured under consideration of the top edge OKA as the point at which the upper edge OK forms the front edge 36. Here, the highest point of the lateral air deflector blade 10 is formed.
(46) As can be seen in FIG. 10, the upper edge OK is developed in a downward curved way. The variant is equivalent to the contour described with reference to FIG. 9a. Accordingly, the upper edge develops a downward-drawn convex curved feed. This feed preferably extends at the front edge 36 from a horizontal line. The feed, however, can also be slightly tilted downward by up to 5° in relation to the horizontal plane. There is no need to say that the front edge 36 in the vertical plane is shaped linearly and that it extends strictly in the vertical plane.
(47) As illustrated in FIG. 11, the top-side air deflector blade 12 shown in the top view and in the operating position has an outline on its rear edge. The contour of the top-side air deflector blade 12 is symmetric to a central longitudinal axis 62 that is equivalent to the central longitudinal axis of the vehicle in the direction of travel. On the rear edge 44, the top-side air deflector blade 12 forms two linear lateral sections LA which extend in parallel to the front edge 36. The side edges have a lateral contour SK as described above with reference to FIG. 9. Accordingly, the lateral contours are convex curved and extend on the front edge 36 with an angle smaller than 5°, preferably with an angle of 0°, from a parallel line to the central longitudinal axis 62. The lateral contours SK are respectively convex curved towards the inside and develop a feed with the feed length E as described with reference to FIG. 9a. As further shown in FIG. 11, the trough MU extends with a lateral distance SA of between 0.20 and 0.30, preferably of 0.23 and 0.27 of a width B of the upper air deflector blade 12, from the linear lateral section LA. This lateral distance SA is ablated at the front edge 36, i.e. on the point of maximum extension of the air deflector blade 12 in the width direction. The trough MU has a concave trough bottom which is evenly arranged by means of eventually convex trough edges in proximity to the linear lateral section LA in the form of a tangent and which merges into this lateral section. In its center, i.e. on the central longitudinal axis 62, the trough MU has a feed with the distance [D] of presently 0.2 of the length L, whereby L is presently indicated with 500 mm and whereby the width of the trough MU amounts to 0.5 of the width B. The dimension [A] can amount to between 0.15 and 0.25 of the length L, preferably between 0.18 and 0.22 of the length L.
(48) Further details as well as dimensions and modifications of the lateral air deflector blade 10 and/or the top-side air deflector blade 12 can be derived from FIGS. 12a and 13a as well as the tables 12b and/or 13b included in these figures. They indicate absolute and relative dimensions with the individual measurement points indicated in FIGS. 12 and 13. With regard to the length and the feed length, reference is made again to FIG. 9a and the special description presented in this respect. The dimensions for the length L and the feed length E are further mentioned in Claim 8.
(49) FIG. 14 illustrates a design example for pressurized air supply within the air deflector blades 10, 12; the solid lines respectively show the air deflector elements 14, 18. The dotted lines represent the planned sliding elements 16, 20 in the operating position. As shown, between the air deflector elements 18, 14, there is a tube piece 64 bent by approximately 90°, which is tiltably and relocatably guided in the air deflector elements 14, 18 and which forms a section of a pneumatic line to transfer pressurized air from the bottom through the lateral air deflector blade 10 to the top-side air deflector blade 12. Due to their design, the air deflector blades 10, 12 are linked to each other by a form-locked connection.
(50) FIG. 15 illustrates the control of the air deflector blades 10, 12 regardless of the speed of the vehicle. The latter is plotted on the horizontal axis while the time is displayed on the coordinate.
(51) At the time t=0, the vehicle starts moving. In a first section (for example a feeder road to the highway), the vehicle drives below a first speed limit. This speed limit is stored in the control system and triggers the shift of the air deflector blades from the stowing position to the operating position. If a speed signal that indicates the first speed limit is registered by the control system, the positioning of the air deflector blades 10, 12 will not yet be triggered directly. Rather, the control unit has a delay module that checks whether the first speed limit will be undercut again in a predefined time interval. In this case, no signal to trigger the shift of position will be sent out. Accordingly, the air deflector blades 10, 12 remain in the stowing position in the second section. In this second section, the measured speed varies in the range around the first speed limit whereby it is both exceeded and undercut. The speed limit is always exceeded for a shorter time than indicated by the predefined period.
(52) In the third section, a much higher speed is generated. Although the actual speed varies, it does never undercut the first speed limit. After that, the air deflector blades 10, 12 are put out and brought into the operating position in an initial phase of the first section and after the end of a predefined period.
(53) In the fourth section, the speed decreases. However, it varies in the range around a second speed limit that is lower than the first speed limit in the shown design example. The second speed limit is undercut in the fourth section for a shorter time than the respective predefined period. This way, the control unit sends out no signal that triggers the air deflector blades 10, 12 to be shifted back from the operating position to the stowing position. Only in the fifth section, the second speed limit is permanently undercut. Hence, a signal is sent out at the beginning of the fifth section and after the end of the predefined time interval by means of which the air deflector blades 10, 12 are shifted back to the stowing position by their associated actuators.
(54) The described control unit prevents the air deflector blades 10, 12 from being permanently opened and closed in case of speed variations in the range of the speed limits.
(55) FIG. 16 shows a design example for the activation of the lateral air deflector blade 10. As can be seen, the air deflector element 18 is installed on an axial rod 66 by means of the rear joint rod 50 and can be moved in an axial direction in relation to this axial rod 66. On the level of this axial rod 66 there is a lifting cylinder shaped as a double-acting pneumatic cylinder 68 whose piston rod shapes a swivel axis body 70. This swivel axis body 70 is firmly connected with the front joint rod 42 which is hinged to the air deflector blade 10. The front joint rod 42 passes through a helical groove 72 that is recessed in a stationary sleeve 74 which essentially takes up the swivel axis body.
(56) When the pneumatic cylinder 68 is activated, the swivel axis body 70 is moved accordingly in the axial direction within the sleeve. The air deflector blade 10 is moved translationally in the longitudinal direction of the axial rod 66 in the process. A the same time, the helical groove 72 makes a swivel movement that causes a further outward shift in relation to the axial extension of the axis rod 66 although it is to be installed in parallel to the swivel axis of the axis rod 66.
(57) The design example shown in FIG. 16 is a possible and relatively simple and effective arrangement to set the lateral air deflector blade in an upright position. Through activation of the pneumatic cylinder, the air deflector blade is therefore not only swiveled, but at the same time also lifted so that the air deflector blade with its upper edge can be positioned evenly on the upper edge of the vehicle in the operating position and arranged in the stowing position at a distance to the outer contour of the rear of the vehicle.
LIST OF REFERENCE SIGNS
(58) 1 Semi-trailer 2 Top area 4 Longitudinal side area 6 Rear area 8 Flow control device 10 Lateral air control wing 12 Upper air control wing 14 Air deflector element of the top air deflector blade 12 16 Sliding element of the top air deflector blade 12 18 Air deflector element of the lateral air deflector blade 10 20 Sliding element of the lateral air deflector blade 10 22 Corner area 24 Outer surface of the lateral air deflector blade 10 26 Outer surface of the top air deflector blade 12 28 Doors 30 Central vertical axis 32 Outer area 34 Inner area 36 Front edge 38 First hinge point on the blade 40 External hinge point on the fixation unit 42 Front joint bar 44 Rear edge 46 Second hinge point on the blade 48 Internal hinge point on the fixation unit 50 Rear joint bar 52 Rear vehicle edge 54 Assembly plate 56 Segment of the top-side air deflector blade 12 58 Fitting case 60 End cap 62 Central longitudinal axis 64 Pipe section 66 Axial rod 68 Pneumatic cylinder 70 Swivel axis body 72 Helical groove 74 Sleeve I Operating position II Stowing position A Distance [A] Trough depth AUK Distance dimension of the lower contour LC B Width of the top-side air deflector blade 12 E Feed length EB Indentation EBOE Upper end of the indentation ID EBUE Lower end of the indentation ID H Height HKA Rear edge section HKA.sub.1 Lower segment of the rear edge section RES HKA.sub.2 Upper segment of the rear edge section RES KM Modified contour KU Initial contour L Length LA Lateral section LR Longitudinal edge MU Trough OK Upper edge OKA Top edge PA Break-off point R Rectangle UK Lower contour UKA Bottom edge QR Transversal edge SA Lateral distance SK Lateral contour Z Intermediate position
