CA2905596C - Modular aerodynamic skirt - Google Patents

Abstract

This invention relates to aerodynamic trailer skirts adapted to be mounted on trailers to improve the aerodynamic efficiency of the trailer. The present invention more precisely relates to a modular self-repositioning aerodynamic skirt assembly with reduced size skirt panel portions and improved shock transmission properties.

Description

2

3 FIELD OF THE INVENTION

4 [0001] This invention relates to aerodynamic trailer skirts adapted to be mounted on trailers to improve the aerodynamic efficiency of the trailer. The present invention 6 more precisely relates to a modular aerodynamic skirt assembly.

9 [0002] Road tractors are generally used to pull trailers on roads to transport cargo. Aerodynamic apparatuses can be installed on the road tractor and/or on the 11 trailer in order to reduce the aerodynamic air drag and improve fuel efficiency.
12 [0003] Trailer aerodynamic skirts are generally parallelly installed on both 13 longitudinal sides of a trailer to help manage the flow of air around and underneath the 14 trailer. Brackets are affixed to the trailer to secure the aerodynamic skirts positioned thereto. These aerodynamic skirts are secured to the bottom portion of the trailer, or on 16 the sides of the trailer's floor, to ensure proper positioning when the vehicle is moving.
17 [0004] People who are familiar with the trucking industry know that trailers are 18 subject to hazardous road conditions. The aerodynamic skirts, because of their position 19 under the trailer's floor and their proximity with the road, are significantly vulnerable and might easily enter in contact with surrounding obstacles. The brackets holding the 21 aerodynamic skirts, when put under significant stress, plastically bend and/or break to 22 effect the aerodynamic skirts' position in respect to the trailer thus reducing the 23 efficiency of the aerodynamic skirts. Moreover, the aerodynamic skirt itself might bend 24 and/or break if they contact a foreign object. This also increases the operation cost and the maintenance time that is required.

1 [0005] The size of the aerodynamic skirts is substantial and shipping uninstalled 2 aerodynamic skirts for remote installation is cumbersome. Aerodynamic skirts are 3 generally considered by shipping companies to be of non-standard sizes and are too 4 large to fit on a standard shipping pallet. They can be damaged during transport from the factory to the installation garage where the aerodynamic skirts are going to be 6 installed on the vehicle because of their length and their width.
7 [0006] Aerodynamic skirts assembly are sustaining a significant amount of stress 8 when deflecting air in their operating positions on a vehicle. Mechanical stresses and 9 sustained vibrations are challenging the skirt assembly.
[0007] Therefore, there exists a need in the art for an improved aerodynamic skirt 11 over the existing art. There is a need in the art for such an aerodynamic skirt assembly 12 that can be easily and economically packaged and shipped. There is also a need in the 13 art for an improved modular aerodynamic skirt assembly that is not jeopardizing the 14 mechanical integrity of the aerodynamic skirt assembly. Moreover, there is also a need for a modular aerodynamic skirt assembly that is appropriately sustaining vibrations 16 caused by the vehicle circulating on the road.

19 [0008] It is one aspect of the present invention to alleviate one or more of the drawbacks of the background art by addressing one or more of the existing needs in the 21 art.
22 [0009] Accordingly, an aspect of our work, in accordance with at least one 23 embodiment thereof, provides an improved aerodynamic trailer skirt over the prior art.
24 [0010] An aspect of our work, in accordance with at least one embodiment thereof, provides an aerodynamic skirt assembly adapted to be installed on a trailer to 26 reduce the aerodynamic drag produced by the movement of the trailer when pulled by a 27 road tractor.

1 [0011] An aspect of our work, in accordance with at least one embodiment 2 thereof, provides a resilient aerodynamic skirt assembly that is adapted to bend when it 3 contacts a foreign object and to self-recover its original position and shape thereafter.
4 [0012] An aspect of our work, in accordance with at least one embodiment thereof, provides a resilient aerodynamic skirt assembly that can be easily installed and 6 economically manufactured.
7 [0013] An aspect of our work, in accordance with at least one embodiment 8 thereof, provides a modular aerodynamic skirt including a plurality of skirt portions 9 configured to be assembled together.
[0014] An aspect of our work, in accordance with at least one embodiment 11 thereof, provides a modular aerodynamic skirt including a plurality of skirt portions sized 12 and designed to be packaged on a cargo pallet with other struts and connectors for 13 reduced shipping size.
14 [0015] An aspect of our work, in accordance with at least one embodiment thereof, provides a plurality of skirt portions sized and designed to be secured together 16 to form a complete aerodynamic skirt assembly adapted to be installed on a trailer in an 17 operating aerodynamic configuration.
18 [0016] An aspect of our work, in accordance with at least one embodiment 19 thereof, provides a plurality of skirt portions sized and designed to be secured together, the skirt portions being secured together with cooperating edges locates at an angle 21 from vertical, when installed on a trailer, to distribute mechanical stresses thereof when 22 the aerodynamic skirt assembly is bending when contacting a foreign object.
23 [0017] An aspect of our work, in accordance with at least one embodiment 24 thereof, provides a plurality of skirt portions sized and designed to be secured together with cooperating edges disposed at an angle from vertical to form a complete 26 aerodynamic skirt assembly and reduces stresses, forces, moments and displacements 27 the aerodynamic skirt assembly experiences by sharing the loads on several fasteners 28 securing the skirt portions together.

1 [0018] An aspect of our work, in accordance with at least one embodiment 2 thereof, provides a plurality of skirt portions sized and designed to be secured together 3 in a fashion allowing a progressive transfer of a wave traveling therein caused by a 4 shock applied on the skirt from one skirt portion to an adjacent skirt portion.
[0019] An aspect of our work, in accordance with at least one embodiment 6 thereof, provides a plurality of skirt portions sized and designed to be secured together 7 with cooperating edges disposed at an angle of about 100 from vertical to form a 8 complete aerodynamic skirt assembly and to reduce stresses, forces, moments and 9 displacements the aerodynamic skirt assembly by simultaneously sharing the loads on several fasteners securing the skirt portions together.
11 [0020] An aspect of our work, in accordance with at least one embodiment 12 thereof, provides an aerodynamic skirt assembly designed to have a natural frequency 13 that is different from the excitation frequency of the trailer in motion.
14 [0021] An aspect of our work, in accordance with at least one embodiment thereof, provides supports securing the skirt to the trailer disposed at the junction 16 between adjacent skirt portions to reduce the mechanical stress at cooperating 17 interconnecting edges thereof.
18 [0022] An aspect of our work, in accordance with at least one embodiment 19 thereof, provides a method of locating skirt supports in locations reducing or modifying the natural frequency of the aerodynamic skirt assembly.
21 [0023] An aspect of our work, in accordance with at least one embodiment 22 thereof, provides an aerodynamic skirt assembly positioning supports thereof at 23 locations causing a reduction or a modification of the natural frequency of the 24 aerodynamic skirt assembly.
[0024] An aspect of our work, in accordance with at least one embodiment 26 thereof, provides an aerodynamic skirt assembly made of composite materials offering a 27 significant range of elastic deformation.

1 [0025] An aspect of our work, in accordance with at least one embodiment 2 thereof, provides a resilient strut adapted to secure a skirt panel to a trailer, the strut 3 being made of a resilient material adapted to sustain significant deformation and 4 adapted to resiliently self-recover its original shape.
[0026] An aspect of our work, in accordance with at least one embodiment 6 thereof, provides strut supports made of non-metallic material.
7 [0027] An aspect of our work, in accordance with at least one embodiment 8 thereof, provides a shock-resistant trailer aerodynamic skirt that is sized and designed.
9 to allow a temporary deflection of a bottom portion of the skirt panel upon contact of a foreign object.
11 [0028] An aspect of our work, in accordance with at least one embodiment 12 thereof, provides a fastening system for easily securing the skirt panel to the trailer; the 13 fastening system uses a limited number of parts to reduce the assembly time and the 14 weight added to the trailer.
[0029] An aspect of our work, in accordance with at least one embodiment 16 thereof, provides an aerodynamic skirt assembly comprising a plurality of support 17 members adapted to secure the skirt panel to the trailer.
18 [0030] Embodiments of the present invention provides a skirt assembly kit 19 comprising a plurality of cooperating skirt panels adapted to longitudinally be disposed on a trailer to route air about the trailer, a plurality of upper supports adapted to secure 21 the skirt panel to the trailer and a plurality of struts adapted to secure the skirt panel to 22 the trailer.
23 [0031] An aspect of our work, in accordance with at least one embodiment 24 thereof, provides an aerodynamic modular skirt assembly having a reduced size for shipping. The larger parts of the modular skirt assembly, the pair of skirt panels, are 26 separated in a plurality of smaller skirt portions adapted to be superposed for reducing 27 the cargo size.

5 1 [0032] An aspect of our work, in accordance with at least one embodiment 2 thereof, provides a shipping configuration using at least one of the skirt portions on two 3 opposed sides of a cargo arrangement and locate the additional parts of the modular 4 aerodynamic skirt assembly between skirt portions for reduced cargo size and strength of the cargo arrangement.

6 [0033] An aspect of our work, in accordance with at least one embodiment

7 thereof, provides a modular aerodynamic skirt assembly for reducing the air drag of a

8 trailer, the modular aerodynamic skirt assembly comprising a skirt panel including a

9 plurality of skirt portions; and a plurality of supports for securing the plurality of skirt portions to a trailer in an aerodynamic configuration when the modular skirt panels are 11 secured to the trailer, wherein adjacent skirt portions are connected together with an 12 interconnecting edge disposed at a non-90 angle from vertical when the plurality of 13 skirt portions are operatively secured in the aerodynamic configuration.
14 [0034] An aspect of our work, in accordance with at least one embodiment thereof, provides a trailer including a modular aerodynamic skirt assembly for reducing 16 the air drag of a trailer, the modular aerodynamic skirt assembly comprising a skirt 17 panel including a plurality of skirt portions; and a plurality of supports for securing the 18 plurality of skirt portions to a trailer in an aerodynamic configuration when the modular 19 skirt panels are secured to the trailer, wherein adjacent skirt portions are connected together with an interconnecting edge disposed at a non-90 angle from vertical when 21 the plurality of skirt portions are operatively secured in the aerodynamic configuration.
22 [0035] Other embodiments and further scope of applicability of the present 23 invention will become apparent from the detailed description given hereinafter.
24 However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration 26 only, since various changes and modifications within the spirit and scope of the 27 invention will become apparent to those skilled in the art from this detailed description.
28 [0036] Additional and/or alternative advantages and salient features of the 29 invention will become apparent from the following detailed description, which, taken in 1 conjunction with the annexed drawings, disclose preferred embodiments of the 2 invention.

[0037] Referring now to the drawings which form a part of this original disclosure:
6 [0038] Figure 1 is a perspective view of a road tractor operatively connected to a 7 trailer including a skirt assembly secured thereto;
8 [0039] Figure 2 is a left elevational view of the road tractor of Figure 1;
9 [0040] Figure 3 is a bottom plan view of the road tractor of Figure 1;
[0041] Figure 4 is a left elevational view of a trailer of Figure 1;
11 [0042] Figure 5 is an elevational side view of a skirt;
12 [0043] Figure 6 is an elevational view of a skirt portion;
13 [0044] Figure 7 is an elevational view of a skirt portion;
14 [0045] Figure 8 is an elevational view of a skirt portion;
[0046] Figure 9 is a section view of an interconnecting edge of a skirt portion;
16 [0047] Figure 10 is a section view of an interconnecting edge of a skirt portion;
17 [0048] Figure 11 is a bottom-right isometric view of a trailer's floor beams and a 18 skirt assembly;
19 [0049] Figure 12 is a right side elevational view of a skirt assembly;
[0050] Figure 13 is a top plan view of a skirt assembly;
21 [0051] Figure 14 is a front-right isometric view of a skirt assembly;

1 [0052] Figure 15 is a rear elevational view of a skirt assembly secured to a trailer 2 floor;
3 [0053] Figure 16 is a right elevational view of a skirt assembly;
4 [0054] Figure 17 is a top plan view of a skirt assembly secured on beams of a trailer floor;
6 [0055] Figure 18 is a magnified portion of an isometric view of a support member 7 secured to a beam of a trailer floor;
8 [0056] Figure 19 is a side elevational view of a support member secured to a 9 beam of a trailer floor;
[0057] Figure 20 is a section view of a connection mechanism securing a resilient 11 strut to a trailer floor beam;
12 [0058] Figure 21 is a section view of a connection mechanism securing a resilient 13 strut to a trailer floor beam;
14 [0059] Figure 22 is a section view of a connection mechanism securing a resilient strut to a skirt portion;
16 [0060] Figure 23 is a section view of a connection mechanism securing a resilient 17 strut to a skirt portion and a trailer floor beam;
18 [0061] Figure 24 is a schematic illustration of a resilient strut in the aerodynamic 19 configuration;
[0062] Figure 25 is a schematic illustration of a resilient strut proximally bent 21 away from the aerodynamic configuration;
22 [0063] Figure 26 is a schematic illustration of a resilient strut in the aerodynamic 23 configuration;

1 [0064] Figure 27 is a schematic illustration of a resilient strut proximally bent 2 away from the aerodynamic configuration;
3 [0065] Figure 28 is a schematic illustration of a resilient strut in the aerodynamic 4 configuration;
[0066] Figure 29 is a schematic illustration of a resilient strut distally bent away 6 from the aerodynamic configuration;
7 [0067] Figure 30 is a side elevational view of a skirt panels assembly joined with 8 an angled interconnecting edge;
9 [0068] Figure 31 is a side elevational view of a skirt panels assembly joined with a straight vertical interconnecting edge;
11 [0069] Figure 32 is a top plan view of a skirt panels assembly;
12 [0070] Figure 33 is a top schematic plan view of a skirt panel with moment and 13 shear forces thereon;
14 [0071] Figure 34 is a schematic side elevational view of a skirt panels assembly joined with vertical interconnecting edges schematically illustrating an exemplary shock 16 wave transmission along the skirt panel;
17 [0072] Figure 35 is a schematic side elevational view of a skirt panels assembly 18 joined with an angled interconnecting edge schematically illustrating a vectorial force 19 separation of an exemplary shock wave transmission along the skirt panel;
[0073] Figure 36 is a schematic illustration of a graph with showing a forced 21 frequency curve and a natural frequency curve of an aerodynamic skirt assembly;
22 [0074] Figure 37 is a schematic flow chart in accordance with an embodiment of 23 the present application;
24 [0075] Figure 38 depicts an isometric view of a cargo configuration in accordance with an embodiment of the present application;

1 [0076] Figure 39 depicts an isometric view of a cargo configuration in accordance 2 with an embodiment of the present application;
3 [0077] Figure 40 depicts a top plan view of a cargo configuration in accordance 4 with an embodiment of the present application;
[0078] Figure 41 depicts a top plan view of a cargo configuration in accordance 6 with an embodiment of the present application;
7 [0079] Figure 42 depicts a top plan view of a cargo configuration in accordance 8 with an embodiment of the present application;
9 [0080] Figure 43 depicts an isometric view of a cargo configuration in accordance with an embodiment of the present application;
11 [0081] Figure 44 depicts an isometric view of a cargo configuration in accordance 12 with an embodiment of the present application;
13 [0082] Figure 45 depicts a top plan view of a cargo configuration in accordance 14 with an embodiment of the present application; and [0083] Figure 46 depicts a skirt portions staking for compact and secure 16 transportation thereof.

19 [0084] A preferred embodiment of the present invention is described bellow with reference to the drawings.
21 [0085] Figures 1, 2 and 3 illustrate a road tractor 10 with a trailer 20 attached 22 thereto equipped with a pair of skirt panels 31, installed on each side of the trailer 20, 23 adapted to deflect and direct the airflow around the trailer 20 when assembled to the 24 trailer 20. Each skirt assembly 30 includes a skirt panel 31 including a plurality of skirt portions 32.1, 32.2, 32.3, adapted to be disposed on the side of the trailer 20, and a 26 plurality of securing members adapted to secure the skirt portions 32.1, 32.2, 32.3 to the 1 trailer 20. Once installed on the trailer 20, the skirt assembly 30 helps channel the flow 2 of air around the trailer 20 to reduce the air drag of the vehicle when the trailer 20 3 moves on the road, pulled by the road tractor 10.
4 [0086] Each skirt assembly includes three skirt portions 32.1, 32.2, 32.3 as exemplified in the illustrated embodiment. A different number of skirt portions 32 6 remains within the scope of the present invention although three skirt portions 32.1, 7 32.2, 32.3 is one preferred embodiment. Securing members securing the skirt panels 31 8 in an operating configuration on the trailer 20 are not illustrated on Figures 1, 2 and 3 9 and will be discussed in more details later in this specification.
[0087] The skirt assembly 30 of the present embodiment is mostly attached 11 under the trailer 20, between the wheels 12 of the road tractor 10 and the wheels 26 of 12 the trailer 20. The assembled skirt portions 32 can alternatively extend forward up to the 13 trailer supports 14 of the trailer 20, and be secured thereto, thus preventing complex 14 skirt portions 32 arrangements around, or through, the trailer supports 14. The skirt portions 32 are substantially vertically positioned on each side of the trailer 20, 16 preferably on the lower edge of the trailer 20 vertical sidewalls, with a clearance with the 17 ground by illustratively about 15-25 centimeters (about 6 to 10 inches) while other 18 clearances remain within the scope of the present application. The air management 19 around the trailer 20 provided by the skirt assembly 30 reduces the air drag created by the trailer 20 by directing the flow of air around and under the trailer 20.
The flow of air 21 would otherwise turbulently move around and under the trailer 20 to create substantial 22 air drag having a negative effect on the aerodynamics of the trailer 20.
The airflow 23 management around the trailer 20 provided by the skirt assembly 30 helps maintaining 24 laminar airflow around the trailer 20 that helps diminish fuel consumption of the road tractor 10. The skirt assembly 30 also improves the safety of the vehicle by providing a 26 physical barrier that can significantly prevent foreign objects to get under the trailer 20.
27 [0088] As illustrated, the assembled skirt 30 is shaped with an optional 28 progressive height of the front skirt portion's 32.1 forward section.
The skirt panels 32 29 can alternatively also be installed at an angle, in respect to the vertical, on the trailer 20 1 to change the airflow pattern around the trailer 20 and more precisely adjust the 2 aerodynamics to a particular vehicle shape and use.
3 [0089] It can be appreciated from Figure 3 that each skirt panel portion 32 is 4 installed directly on the side's edge of the trailer 20 and, when seen from above, has a front portion 34 that progressively proximally leans toward a longitudinal center 24 of the 6 trailer 20. The recessed front skirt portion 32.1 of the assembled skirt portions 32 7 improves the collection and routing of the turbulent airflow generated by the road tractor 8 10 thus improving the aerodynamic performance of the skirt assembly 30.
Additional 9 details about the shape of the skirt panel 31 will be provided in further details below. A
right side of the trailer 20 equipped with a skirt assembly 30 is illustrated in Figure 4.
11 Each skirt assembly includes three skirt portions 32.1, 32.2, 32.3 in the illustrated 12 embodiment. The skirt portions are embodied as three (3) different skirt portions 32 to 13 split the length of the complete skirt panel 31 and facilitate its handling and shipping.
14 Three skirt portions 32.1, 32.2, 32.3 in the present situation seems to shorten the skirt portions 32.1, 32.2, 32.3 in a sized compatible with standard shipping methods, 16 however, a different number of skirt portions 32 could be used without departing from 17 the scope of the present invention. The longitudinal length of each of the skirt portions 18 32.1, 32.2, 32.3 can be adapted to different configurations. In the present situation, the 19 middle skirt portion 32.2 is embodied as the larger skirt portion 32 because, for instance, of its rather rectangular shape. Other proportions of skirt portion 32 lengths 21 could be used without departing from the scope of the present invention.
22 [0090] Skirt portions 32 assembly is illustrated in Figure 4 and its components are 23 depicted in Figure 5 throughout Figure 9. Figure 6 depicts the forward skirt portion 32.1.
24 The forward skirt portion 32.1 is embodied with a straight vertical front edge 100, an upper rectilinear edge 104 adapted to match the bottom edge of the trailer 20, an 26 angled bottom edge 108 configured to progressively manage the airstream around the 27 trailer 20 and a rear edge 112 adapted to connect with the middle skirt portion 32.2. The 28 rear edge 112 is preferably at an angle a to increase the mechanical strength of the skirt 29 portions 32 assembly; the effect of angle a is going to be discussed below in greater details. The angle a create an obtuse angle 80 allowing the lower edges 84 of the 1 middle skirt portion 32.2 and the rear skirt portion 32.3 to slip over an external object 88 2 when the aerodynamic skirt assembly 30 is installed in an aerodynamic configuration 3 and the trailer 20 is moving in a forward direction.
4 [0091] The forward skirt portion 32.1 is assembled to the middle skirt portion 32.2 with a plurality of fasteners 116, like bolts, rivets or other means adapted to secure the 6 skirt portions 32.1, 32.2, 32.3 together. The middle skirt portion 32.2 illustrated in Figure 7 7 includes an upper edge 120, a bottom edge 124 a forward edge 128 and a rearward 8 edge 132. The upper edge 120 and the bottom edge 124 are embodied parallel to one 9 another. The forward edge 128 and the rearward edge 132 are interconnecting edges 136 configured to receive and secure thereto respectively the forward skirt portion 32.1 11 and the rear skirt portion 32.3. The two interconnecting edges 136 are located on the 12 middle skirt portion 32.2 to restrict the complexity provided by the interconnecting edges 13 136 the panels 32.1, 32.2, 32.3 to a single panel portion 32.2. Each interconnecting 14 edge 136 includes a recessed portion 140 adapted to secure thereon the cooperating edge of the adjacent skirt portion 32. The recessed portion can extend about 37 mm 16 (-1.5") of flat section that is shaped directly in the middle skirt portion 32.2. The 17 recessed portion 140 is proximally recessed of the equivalent of the thickness of the 18 skirt 32 sheet material, which is illustratively of about 6 mm (-0.25"), to overlap and joint 19 the adjacent skirt portions 32.1, 32.2, 32.3. This embodiment is illustrated in Figure 9.
Alternatively, an additional interconnecting part 148 can be used to secure together two 21 adjacent skirt portions 32 (illustrated in Figure 10). The additional interconnecting part 22 148 would then be secured on the proximal side of the two adjacent skirt portions 32.
23 Both configurations are ensuring that the distal surface of the assembled skirt portions 24 32 is flush, at the same level 144, and facilitate the airflow thereon.
The interconnecting edge 136 includes a plurality of holes 152 sized and designed to receive therein 26 fasteners 116 to secure the assembly; e.g. 8 mm (-5/16") bolts.
27 [0092] The rear portion 32.3 exemplified in Figure 8 includes a forward edge 156, 28 a rearward edge 168, an upper edge 160 and a bottom edge 164. In the present 29 configuration, the forward edge 156 is configured to be assembled with the rear interconnecting edge 132, 136 of the middle skirt portion 32.2.

1 [0093] Figure 11 is a perspective image of the skirt assembly 30 installed on the 2 left side of a trailer 20 from which is only illustrated a series of frame members 23 3 forming a portion of the trailer floor frame 22. A series of support members 40 are 4 secured to the trailer to secure the juxtaposed skirt panels 31 thereto.
The support members 40 could be omitted altogether and the skirt panel could alternatively be 6 attached directly to the trailer 20 without deviating from the scope of the present 7 application. The rear portion of the skirt panel 31 is preferably positioned on the edge of 8 the trailer's wall 28. It is also covered by the present invention that the skirt panel 31 9 could be installed a little in recess about the side of the trailer 20 to avoid winches, lights, toolbox or ladders located on the side/edge of the trailer 20. In contrast, it can be 11 appreciated that the front skirt portion 32.1 of the skirt panel 31 is progressively 12 positioned and secured toward the center 24 of the trailer 20. The skirt panel 31 is 13 secured adjacent to the frame 22 with a series of support members 40 secured to both 14 the frame members 23 and the skirt panel 31. Lower, the skirt panel 31 is secured to the trailer 20 with a series of intervening resilient struts 42 also secured to both the frame 16 members 23 and the skirt panel 31. Additional details about the support members 40 17 and the resilient struts 42 are provided later in reference with other Figures.
18 [0094] Still referring to Figure 11, it can be appreciated that the upper series of 19 holes 35 disposed on a top portion of the skirt panel 31 is used to fasten the skirt panel 31 to respective support members 40 that, themselves, are secured to frame members 21 23 of the trailer 20. A number of connection points between the skirt panel 31 and the 22 trailer 20 are used to ensure the skirt panel 31 is well secured to the trailer 20 and will 23 not vibrate or deflect (however some deflection can be acceptable under certain 24 conditions) during operation. The series of holes 35 disposed on a lower portion of the skirt panel 31 are adapted to attach to an end of each resilient strut 42.
Similarly, with 26 this configuration of struts 42, the other end of the resilient strut 42 is connected to the 27 frame members 23 of the trailer 20 via a fastener mechanism that will be discussed 28 below in details.
29 [0095] Figure 12 throughout Figure 15 are additional views of the skirt assembly 30. It can be further appreciated that a curved portion 38 is defined on the rear portion 1 36 of the skirt panel 31 and preferably corresponds to the exterior shape of the adjacent 2 wheels 26 of the trailer 20. In so doing, it is possible to install the skirt panel 31 close to 3 the wheels 26 without risking any contact thereto. It is preferable to leave a distance 4 between the wheels 26 of the trailer 20 and the skirt panel 31 to avoid any risk of interference therebetween.
6 [0096] The wheels 26 of a trailer 20 are commonly adapted to be longitudinally 7 adjustable to distribute the mass of the trailer 20 in a desired fashion.
The adjustment of 8 the position of the axels of a trailer 20 is desirable, for instance, when a heavy load is 9 carried or during thaw and freeze periods. In this respect, and to avoid reinstalling the skirt panel 31 in various positions on the trailer 20, it might be desirable to install the 11 skirt panel 31 in respect with the forwardmost possible position of the axels of the trailer 12 20. That would prevent to remove and reposition the skirt panel 31 when the trolley's 16 13 position is modified.
14 [0097] The trailer wheels 26 are mounted on a trailer buggy 16 adapted to move the wheels 26 along a portion of the trailer's length to distribute the weight of the trailer 16 20 in a desired fashion. The skirt assembly 30 is preferably permanently secured to the 17 trailer 20 taking in consideration the forwardmost position of the trailer buggy 16. The 18 gap between the skirt panel 31 and the trailer's wheels 26 is however increased when 19 the trailer buggy 16 is move toward the rear of the trailer 20 thus likely reducing the aerodynamic efficiency of the skirt assembly 30. The present invention provides a skirt 21 panel extension module 33 adapted to reduce the gap between the skirt panel 31 and 22 the trailer's wheels 26 to prevent any aerodynamic efficiency reduction.
The skirt panel 23 extension modules 33 are secured to the trailer in a similar fashion.
The skirt panel 24 extension module 33 can be provided in various lengths to fill gaps of various sizes.
They can also be provided as skirt panel extension modules 33 kit. An alternate 26 embodiment provides a sliding skirt panel extension 33 that is permanently secured to 27 the trailer 20 and extendable to the desired length when the trailer buggy 16 is moved.
28 [0098] A skirt panel extension 33, illustrated on Figure 16, can alternatively be 29 added between the skirt panel 31 and the wheels 26 when the axles of the trailer 20 are 1 located in a rearward position leaving an increased distance therebetween to improve 2 the aerodynamic efficiency of the skirt assembly 30. A reasonable distance between the 3 skirt panel 31 and the wheels 26 could be between about 15 centimeters and about 30 4 centimeters although a shorter distance, or even a superposition of the skirt panel 31 (or skirt panel module(s) 33) over the wheel 26, can be achieved.
6 [0099] Figure 17 is a top elevation view of the trailer frame 22. As mentioned 7 above, it can be appreciated from Figure 17 that the skirt panel 31 is disposed inwardly 8 on the forward portion of the trailer 20 and is progressively located on the edge of the 9 trailer's wall 28 toward the rear end of the trailer 20. A departure support member 60 and a cooperating forward support member 64 are secured to the trailer to correctly 11 locate the skirt panel 31 on the trailer 20. The departure support member 60 and the 12 forward resilient strut 64 are installed on the trailer 20 prior to install the skirt panel 31.
13 The rear portion 36 of the skirt panel 31 is secured to the trailer 20 up to the departure 14 support member 60 and then the skirt panel 31 is bent to reach the forward support member 64 and secured thereto. That bent locates the skirt panel 31 to the trailer 20 16 and defines the shape of the skirt panel 31 with the desired progressive proximal bent.
17 The remaining support members 62 and resilient struts 42 are installed thereafter to 18 further secure the assembly.
19 [00100] The rear portion 36 of the skirt panel 31 is intended to be secured to the trailer to leave only a minimum gap with the trailer wheels 26 to improve the 21 aerodynamic efficiency of the skirt assembly 30. The skirt panel 31 extends to the front 22 of the trailer 20 and includes a curved portion on its front portion 34.
A long skirt panel 23 31 appears to be more efficient than a shorter skirt panel 31 and should therefore 24 extend as far as possible to the front of the trailer 20. However, for reasons of complexity, the front portion 34 of the skirt panel 31 is likely to stop at the trailer 26 supports 14. It is nonetheless encompassed by the present invention that the skirt panel 27 31 alternatively extends in front of the trailer supports 14. The lowermost portion of the 28 front portion 34 of the forward skirt panel 31.1 is provided with a radius thereof as it is 29 best seen in Figure 16.

1 [00101] In an embodiment of the invention adapted to fit a standard 16.1 meters 2 (-53 feet) long trailer 20 the forward end of the departure support member 60 is located 3 at a distance d1 from the forward end of the skirt panel 31. A forward support member 4 64 is secured to the frame at a distance d2 from the side edge of the trailer 20 as it can be appreciated in Figure 16 and Figure 17. Distance d1 is about between 1.5 meter and 6 3 meters, preferably about between 2 meters and 2.5 meters and most preferably about 7 between 2.1 meters and 2.4 meters. Distance d2 is about between 0.20 meter and 0.40 8 meter, preferably about between 0.25 meter and 0.35 meter and most preferably about 9 0.27 meter and 0.32 meters. More precisely, distance d1 is preferably about 2.29 meters and distance d2 is preferably about 0.31 meter in a preferred embodiment.
11 Corresponding support members 40 and resilient struts 42 are installed to further 12 secure the skirt panel 31 at the desired position.
13 [00102] A left side elevation view schematically illustrating, on Figure 16, the 14 overall size of the skirt panel 31. Length d3 of the skirt panel 31 is about between 5 meters and 9 meters, preferably about between 6 meters and 8 meters and most 16 preferably about between 5.8 meters and 7.5 meters. The height d4of the skirt panel 31 17 is about between 0.5 meter and 1 meter, preferably about between 0.6 meter and 0.9 18 meter and most preferably about between 0.7 meter and 0.9 meter. And the 19 forwardmost height d5 of the skirt panel 31 is about between 0.3 meter and 0.7 meter, preferably about between 0.4 meter and 0.6 meter and most preferably about between 21 0.45 meter and 0.5 meter. More precisely, distance d4 is preferably about 0.81 meter 22 and distance d5 is preferably about 0.48 meter in a preferred embodiment.
23 [00103] Alternate embodiments providing a skirt assembly 30 sized and designed 24 to fit trailers 20 of different lengths can be inferred from the dimensions discussed above. For instance, a skirt assembly 30 can be designed to fit a 14.6 meters (-48 feet) 26 trailer 20 or any other trailer 20 sizes and lengths.
27 [00104] In one embodiment, the skirt panel 31 is made of composite material.
28 Recommended multilayer composite material, fiber reinforced polypropylene, a 29 combination of a polypropylene component and woven component or unidirectional 1 thermoplastic manufactured by Transtex Composites Inc. is used in the present 2 embodiment. The composite material forming the skirt panel 31 of the illustrative 3 example is shaped in a planar material adapted to allow skirt panel 31 to bend when the 4 skirt panel 31 is pushed toward the center of the trailer 20 (proximally) when, for instance, contacting an obstacle or having a force applied thereon. The skirt panel 31 6 bends, allowing a significant displacement of the bottom portion of the skirt panel 31 7 proximally and distally from a longitudinal centerline of the trailer 20, and is adapted to 8 retrieve by itself its original position when the force is removed from the skirt panel 31.
9 As further illustrated in Figure 16, the skirt panel 31 is provided with a series of holes 35 therein used to connect the skirt panel 31 to the support members 40, 42 and 46. The 11 series of holes 35 disposed on the upper portion of the skirt panel 31 is used to connect 12 the skirt panel 31 to the frame 22 of the trailer 20 whereas, in a similar fashion, the 13 series of holes 35 disposed on the bottom portion of the skirt panel 31 is used to 14 connect the skirt panel 31 to the skirt connecting portion 48 of the resilient strut 42. The resilient strut 42 is connected to the frame member 23 of the trailer via the trailer-16 connecting portion 46 of the resilient strut 42. The skirt connecting portion 48 and the 17 trailer-connecting portion 46 include respective series of holes 35 to receive fasteners 18 therein. The holes 35 can be factory pre-drilled or can be drilled during installation to 19 ensure desired customization. Rivets or bolts are placed in the holes 35 to secure the skirt panel 31 to the trailer frame 22 or the support assembly. Other appropriate 21 fastening mechanism variations well known in the art are encompassed by the present 22 disclosure and can be used without departing from the scope of the invention.
23 [00105] An opening 70 is defined in the skirt panel 31 to allow access to an 24 optional fuel tank disposed on the trailer 20 to fuel an onboard generator or freezer.
Such a fuel tank is commonly disposed under the floor 22 of the trailer 20 and is most 26 likely hidden by the skirt assembly 30. The opening is sized, designed and located on 27 the skirt panel 31 to allow access to the fuel tank. A door (not illustrated) can optionally 28 be added to close the opening 70.
29 [00106] Turning now again to Figure 15 where is illustrated a plurality of resilient struts 42 and angles support 40 secured between the frame 22 and the skirt panel 31.

1 The rear elevation view shows that the front portion 34 of the skirt panel 31 is proximally 2 recessed from the left lateral side of the trailer 20 by, illustratively, about 30 centimeters.
3 It can also be appreciated that the skirt panel 31 is held to the trailer frame 22 via the 4 series of angled support 40 on its upper portion. The trailer connecting portion 46 of the resilient strut 42 is connected to the frame member 23 at an angle al, which is an angle 6 of about 45 in the present illustrative embodiment and could be different without 7 departing from the present description.
8 [00107] Figure 18 and Figure 19 are illustrating a close up view of the connection 9 between the skirt portions 32 and the trailer frame members 23 via support members 40. It can be appreciated that the recessed portion 140 of the skirt portion 32.2 is 11 shorter at the top to allow the support member 40 to be in contact with the skirt portions 12 32 all along its length.
13 [00108] In one embodiment, the resilient strut 42 has a rectangular section and is 14 made of composite material. Recommended multilayer composite material, polypropylene component, glass component, fiber reinforced polypropylene, a 16 combination of a polypropylene component and woven component, or reinforced 17 thermoplastic manufactured by Transtex Composites Inc. is used in the present 18 embodiment. The composite material forming the resilient struts 42 of the illustrative 19 example is shaped in a rectangular section to allow the resilient strut 42 to bend when the skirt panel 31 is pushed toward the center of the trailer 20 (proximally) when, for 21 instance, contacting an obstacle or having a force applied thereon. The resilient strut 42 22 bends, allowing a significant displacement of the bottom portion of the skirt panel 31, is 23 adapted to self-retrieve its original position when the force is removed from the skirt 24 panel 31. The resilient strut 42 is preferably made of a one-piece material where both ends are slightly angled 44 to evenly contact the skirt panel 31 and the trailer frame 26 member 23. In so doing, no additional intervening parts are required between the 27 resilient strut 42 and both the skirt panel 31 and the trailer frame member 23.
28 [00109] Figure 20 and Figure 21 depict with more details the connection 29 mechanism between the resilient struts 42 and the trailer frame members 23. One of the 1 resilient strut 42 ends is juxtaposed on the lower surface of the trailer frame 22. A set of 2 holes, identified with holes axes 54, are used to fasten two clamps 50, one on each side 3 of the frame member 23 with fasteners 52, to secure the resilient strut 42 to the trailer 4 frame 22. The clamps 50 can be designed such that they are elastically deforming to secure the frame member 23 and are illustratively made of a shaped stainless steel 6 plate material to prevent corrosion.
7 [00110] Figure 22 illustrates the connection between the resilient strut 42 and the 8 skirt panel 31. The end of the resilient strut 42 is positioned to the surface of the skirt 9 panel 31 and secured thereto. Any types of fasteners 56 can be used to fasten both parts together. Rivets are preferably used to secure the assembly with the resilient strut 11 42 although a bolt could also fit into the holes performed in the skirt panel 31, identified 12 with hole axis 54, to secure the assembly. Glue or resin could alternatively be applied 13 between the resilient strut 42 and the skirt panel 31 to secure the resilient strut 42 and 14 the skirt panel 31 together and is also encompassed by the present invention.
[00111] Figure 23 shows the assembly between the upper portion of the skirt 16 panel 31 and one of the angled supports 40. The support member 40 is disposed next 17 to the edge of the trailer 20 to position the exterior surface of the skirt panel 31 18 significantly co-planar with the lateral wall of the trailer 20. Again, any types of fasteners 19 can be used to fasten both parts together. Rivets are preferably used but a bolt could also fit into the holes 54 in the skirt panel 31 and the angled support 40 to secure the 21 assembly. Here again, glue or resin could alternatively be applied between the support 22 member 40 and the skirt panel 31 to permanently secure the support member 40 and 23 the skirt panel 31 together.
24 [00112] The resilient struts 42 of the present embodiment is about 4 millimeters thick and can reach a flexing radius of about 20 centimeters without reaching plastic 26 deformation, or breaking. In some designs, the thinner the resilient strut 42 is, the 27 shorter will be its maximum radius of curvature. A lateral proximal displacement of about 28 60 centimeters of the bottom portion of the skirt panel 31 is possible.
The lower portion 29 of the skirt panel 31 can even reach, under certain circumstances, a position parallel 1 with the trailer 20 floor. The skirt assembly 30 and the skirt panel 31 will self-recover 2 their original positions when the force causing the bending is removed.
Further, the 3 bending of the resilient struts 42 provides energy absorption in case of impact from 4 another vehicle for example. It can be noted that a distal displacement of the skirt panel 31 is possible. A distal and proximal displacement of the skirt panel 31 will occur when a 6 properly directed force is applied to the skirt panel 31 to bend the skirt panel 31.
7 [00113] Figure 24 throughout Figure 29 illustrate an embodiment where the 8 resilient strut 42 is fixed to the trailer frame 22 and the skirt panel 31 in different possible 9 configurations. A first configuration is illustrated in Figure 24 and Figure 25 illustrated with a force F proximally applied toward the vehicle. Instead of installing the resilient 11 strut 42 with both ends slightly angled to mate with the skirt panel 31, Figure 26 and 12 Figure 27 are illustrating a configuration where both ends of the resilient strut 42 are 13 further angled to contact the skirt panel 31 from the opposite side.
This alternate layout 14 assembly reduces the stress on the resilient strut 42, when the skirt panel 31 is deflected, for instance, under a force F, by expending the radius of curvature of the 16 resilient strut 42 throughout the resilient strut 42 ergo significantly reducing local stress 17 points in the resilient strut 42. Figure 28 and Figure 29 are depicting the same resilient 18 strut 42 configuration as in Figure 24 and Figure 25, this time with a force applied away, 19 distally from the vehicle.
[00114] As would be appreciated by those skilled in the art, in view of the present 21 specification, the nature of the material used to build the skirt panel 31 and the resilient 22 strut 42 can vary. These materials are also contemplated to fall within the scope of the 23 invention if they lead to the flexibility and resilience required to build a resilient skirt 24 assembly 30.
[00115] Figure 30 illustrate a skirt panel 31 including three (3) skirt panel portions 26 32.1, 32.2, 32.3. The interconnecting edges 136 between adjacent skirt portions 32.1, 27 32.2, 32.3 is not located at 90 from the upper and lower edges of the skirt panel 31, in 28 other words the interconnecting edges 136 are not vertical when the skirt panel 31 is 29 mounted on a trailer 20. The interconnecting edges 136 are rather disposed at an angle 1 a from vertical to allow progressive mechanical stress transmission between adjacent 2 skirt portions 32. The mechanical stress can be pictured as a "wave"
transmitted in the 3 skirt panel 31 that is caused by a contact with an external object with the front portion of 4 the skirt panel 31. Generally, the more significant the angle a is, more progressive is going to be the mechanical stress transmission along the skirt panel 31 between 6 adjacent skirt portions 32. For practical and economical reasons, like manufacturing 7 limitations and waste, and shipping size, the angle a is not too large and could be 8 selected among the following values:
Minimum angle a Maximum angle a Range A 0 450 Range B 2 300 Range C 50 15 Range D 775. 12,5 Range E 9. 110 9 Table 1 [00116] All the above ranges are considered to be within the scope of the 11 preferred possible embodiments. Range A, range B and range C are contemplated 12 although their respective range include pronounced angles and an angle of, for example 13 45 , would smoothly distribute the mechanical stress between the skirt portions 32.1, 14 32.2, 32.3 but would produce skirt portions 32.1, 32.2, 32.3 that are longer than a more reduced angle a. Manufacturing acute angles with materials contemplated for 16 constructing the skirt panel 31 could be more challenging, more expansive, could 17 increase the amount of defective parts and increase the risk of injury with sharp edges, 18 as well as increasing waste. Shipping package is consequently going to be larger and 19 thus, costlier. For at least some of these reasons, the angle a of about

10 is going to be considered as a typical angle offering a functional stress distribution while keeping 21 the longitudinal length of the skirt portions 32 to a minimum. The angle a of about 10 is 22 going to be used below for the purpose of the description although it is not intended to 23 limit the range of the angle a for the described invention.

1 [00117] Still referring to Figure 30, a typical cut joint 172 having an angle a, from 2 vertical, of about 10 is illustrated as opposed to a straight 90 vertical cut joint, as 3 illustrated in Figure 31. Still referring to Figure 30, a foreign object getting in contact with 4 the skirt portion 32.1 and causing a shock 176 is going to produce a wave 180 of energy traveling in the skirt 32, for instance, in the longitudinal direction toward the rear of the 6 skirt panel 31. The wave 180 motion traveling in the skirt panel 31 toward the back and 7 is progressively transferred to the second adjacent skirt portion 32.2, and then the third 8 adjacent skirt portion 32.3. The progressive transfer of the energy carried by the wave 9 180 is permitted by the longitudinally progressive interconnecting edge 136 that is at angle a. The wave 180 is going to hit the upper portion of the interconnecting edge 136

11 before the lower portion of the interconnecting edge 136. Conversely, the wave 180

12 motion would not be progressively transferred should the angle a be a straight 90

13 vertical cut joint because the wave 180 would hit the straight 90 vertical cut joint all at

14 the same time over the height of the skirt panel 31, as illustrated in Figure 31. For more details, the skirt panel 31 is seen from a bottom view in Figure 32. Each skirt portion 16 32.1, 32.2, 32.3 is joint with its adjacent skirt portion 32 with fasteners 116 through 17 holes 152 therein at the interconnecting edge 136. The fasteners 116 contemplated in 18 the embodiments could be bolts and nuts, rivets, glue or other types of welding or 19 material fusing. Further simplifying and representing only the center skirt portion 32.2 in Figure 33 with two interconnecting edges 136, one on each end thereof with shear and 21 bending moment distribution along the skirt portion 32.2. Put differently, rotational 22 stiffness is increased with an angle a that is not 90 because of the more significant 23 bending moment that is required to bend it. The longer the interconnecting edges 136 24 are, the higher the bending moment is, hence increasing the rotational stiffness.
[00118] In Figure 33 and Equation 1 below, V= shear Force and M is the bending 26 moment about the interconnecting edge 136. As it is indicated, the shear force per unit 27 of length will cancel and balance each other.
28 [00119] On 10 degree cut skirt, the bending moment per unit deflection required 29 along the joint line is more due to longer joint than that of straight cut joint and results in a more significant rotational stiffness. The bending moment along the skirt panel 31 is I applied with a phase difference at different points on the 10 joint due to its inclination 2 along the length of the skirt panel 31. Therefore, the bending waves cannot be set up 3 easily as in straight case. On 100 degree cut skirt portion 32, the bending wave 4 propagates along the skirt panel 31 from one panel portion 32 to another through the bolted joints one by one, as the bolts are inclined unlike straight cut skirt.
6 [00120] A vibration wave travelling along the length of the skirt with a velocity of V
7 after impacting with 1st joint will tend to change its direction perpendicular to the joint as 8 illustrated in Figure 35. The magnitude of this velocity is the product of initial velocity 9 and cosine of the angle. This phenomenon when observed all along the length of the joint from bottom towards top of the joint, the velocity waves emerging at top portion of 11 the joint will bounce back and forth on the top portion of the panel and these returning 12 waves interfere with primary waves emerging from the joint and hence these waves will 13 be out of phase with respect to each other. While in a straight cut skirt, the wave will 14 propagate and pass onto the next panel without change in direction.
[00121] There is an established standing waves on the straight cut skirt with 16 maximum displacement at anti nodal points as depicted in Figure 34.
While on the 10 17 degree cut skirt portion 32, the displacement is lower as the vibration waves have a 18 change in their course after passing through the inclined joint and have difference in 19 phase. Consequently, there will be less displacement at anti nodal point. As a result, the 10 degree cut skirt portion 32 is superior to a vertically straight cut skirt portion 32.
21 [00122] A more progressive transmission of the bending wave 180 implies that the 22 total energy carried by the bending wave 180 is transmitted over a longer period of time 23 and the maximum peak mechanical stress transmitted to the skirt panel 31 24 interconnecting edge 136 is reduced hence requiring less fasteners 116 to sustain the transmitted mechanical stress from one skirt portion 32.1 to an adjacent skirt portion 26 32.2. The holes 152 are also required to be less sturdy and have a reduced likelihood of 27 breaking under load.
28 [00123] The bending wave propagating progressively from one skirt portion 32.1 to 29 the adjacent skirt portion 32.2 through an angled interconnecting edge 136, the 1 fasteners securing both skirt portions 32 are progressively sustaining the bending wave.
2 The fasteners 116 are supporting peak stress one by one as fasteners are disposed 3 along a 10 angle and not aligned like they are at 90 angle. This effect is represented 4 by the following equation:
V'=V x cos(10 ) 6 Equation 1 7 [00124] This means that, for example:
V angle a V' V-V' Difference (%) 100 = 10 98,48 1,52 -1.5%
8 Table 2 9 [00125] A bending wave 180 travelling along the length of the skirt panel 31 with a velocity of V' after impacting the first joint, at the interconnecting edge 136, will tend to 11 change its direction perpendicular to the interconnecting edge 136. The magnitude of 12 the velocity V' is the product of initial velocity V and cosine of the angle a. The velocity 13 waves emerging at top portion of the interconnecting edge 136 will bounce back and 14 forth on the top portion of the skirt panel 31 when observed all along the length of the interconnecting edge 136, from bottom towards top. In contrast, in a straight 16 interconnecting edge 136 at 90 , the wave will propagate and pass onto the next skirt 17 panel 32 without change in direction.
18 [00126] As a result, illustrated in Figure 35, there is an established standing waves 19 on the straight cut interconnecting edge 136 at 90 with maximum displacement at anti nodal points. While on the 100 degree interconnecting edge 136 skirt panel 32, the 21 displacement is lower as the vibration waves have a change in their course after 22 passing through the inclined interconnecting edge 136 joint and have a difference in 23 phase. Therefore, less displacement at anti nodal point is resulting from a 10 24 interconnecting edge 136 skirt superior to straight 90 interconnecting edge 136 skirt panel 32.

1 [00127] The trailer 10 has a forced frequency about which its mechanical structure 2 becomes "excited" and vibrations of the trailer 10 are transmitted to the skirt assembly 3 30 at the forced frequency. When the mechanical structure of the trailer 10 is excited, it 4 vibrates. Natural frequency is the frequency at which a system tends to oscillate in the absence of any driving or damping force. Free vibrations of any elastic body is called 6 natural vibration and happens at a frequency called natural frequency.
Natural 7 vibrations are different from forced vibration that happen at frequency of applied force 8 (forced frequency). If forced frequency is equal to the natural frequency, the amplitude 9 of vibration increases manifold. This phenomenon is known as resonance.
The natural frequency of the skirt assembly 30 and the forced vibration of the trailer 10, due to trailer 11 10 vibrations, should be different. It is desirable to design and "tune"
a skirt assembly 30 12 in a way that the natural frequency of the skirt assembly 30 is not in sync with the forced 13 frequency of the trailer 20. Experimental testing has found that the skirt assembly 30 14 presented in the embodiments has two natural frequencies. A first natural frequency at about 7.1 Hz and a second natural frequency at about 15.5 Hz. It is therefore desirable 16 that the forced frequency of the trailer 20 be different.
17 [00128] Frequency tuning of the skirt assembly 30 can be made in various ways.
18 One way consists in moving the securing locations of the supports 40 and the struts 42 19 on the skirt panel 31. Changing the securing locations of the supports 40 and the struts 42 is modifying the natural frequencies of the skirt panel 31. Minor changes in the 21 location of a support 40 or a strut 42 can be enough to cause a significant change in the 22 natural frequencies of the skirt panel 31. Disposing supports 40 between two adjacent 23 skirt portions 32.1, 32.2, 32.3 could be efficient to change in the natural frequencies of 24 the skirt panel 31. This is an explanation of how the natural frequencies of the skirt panel 31 is a parameter to consider and one example how to tune the natural 26 frequencies of the skirt panel 31. The natural frequencies of the skirt panel 31 are 27 dependent on various parameters like the size of the skirt, its material, and its shape, 28 among others. It can be evaluated by vibration behavioral analysis. The present 29 invention provides an illustrative example of a specific embodiment however, the consideration of the natural frequencies of the skirt panel 31 and tuning thereof is 31 considered to be within the scope of the present invention. The forced frequency of the 1 trailer 10 can vary depending of the trailer configuration, speed, the material used in its 2 manufacturing, the cargo load, the speed, taken individually or collectively. The 3 installation of the skirt assembly 30 to a trailer 10 can include a method including steps 4 of determining the more significant forced frequencies of the trailer 10 and adjust the installation of brackets to the skirt assembly 30 accordingly. Figure 36 exemplifies the 6 above with a chart illustrating the natural frequencies 184 of the skirt assembly 30 and a 7 forced frequency 188 of the trailer 10. The trailer 10 natural frequencies 184 and peak 8 forced frequencies 188 are not superposed in the illustrated embodiment.
Figure 37 9 illustrate a typical flow chart for determining the tuning of a skirt assembly 30 that could be desirable to avoid a forced frequency that is exciting the natural frequencies of a skirt 11 assembly 30.
12 [00129] Figures 38 throughout Figure 45 are illustrating a cargo configuration 192 13 for shipment of the modular skirt assembly 30. Cargo configuration 192 size of a 14 modular skirt assembly 30 is a fraction of a non-cargo configuration size of a non-modular skirt assembly 30. The cargo configuration 192 embodied in Figures 38 16 throughout Figure 45 is one configuration of parts adapted for shipment and other 17 configurations could become apparent for a skilled reader and remain within the scope 18 of the present application. Figure 38 illustrates the three skirt portions 32.1, 32.2 and 19 32.3 superposed on a first side of a cargo box or the like. The three skirt portions 32.1, 32.2 and 32.3 forming a first layer are thus providing a compact arrangement that offers 21 rigidity to the cargo configuration and also protects the additional parts 200 that are 22 going to be stacked over. The cargo configuration 192 includes preferably two supports 23 196 above and below the three superposed skirt portions 32.1, 32.2 and 32.3 as it is 24 illustrated in Figure 39. The two supports 196 can be made or rigid and inexpensive materials like wood, plastic or cardboard. Then the additional parts 200 are disposed 26 over the stacked skirt portions 32.1, 32.2 and 32.3. The additional parts 200 are 27 preferably secured in boxes 204 for easy manipulation and to prevent relative moments 28 thereof in the cargo configuration 196. The additional parts 200 are generally, for a 29 standard modular skirt assembly 30, struts 42, supports 40 and fasteners 116 as depicted in Figure 41, Figure 42, Figure 43 and Figure 44.

1 [00130] The cargo configuration 192 depicted in Figure 43 includes additional side 2 fillers 208 and bracket box fillers 212 on the upper and lower sides of the cargo 3 configuration 196. Fillers 208, 212 can be embodied as cardboard boxes, foam or any 4 suitable filling material adapted to keep the parts of the modular skirt assembly 30 at their respective locations in the cargo configuration 192. Additional elements to be 6 shipped with the modular skirt assembly 30 can be inserted in the fillers 208, 212 if 7 needed. One can appreciate the opposed symmetrical arrangement of the boxes 204 8 and the fillers 208, 212 to ensure a balanced weight that is going to ease transportation 9 of the cargo load. In turn, figure 45 depicts the final layout of the cargo configuration 192 with the second skirt panel portions 32.1, 32.2, 32.3 stacked on the top of the other 11 parts. The three skirt portions 32.1, 32.2 and 32.3 forming a second layer, opposed to 12 the first layer, are thus providing a compact arrangement that offers rigidity to the cargo 13 configuration and also protects the additional parts that are located between the two 14 layers of skirt portions 32.1, 32.2 and 32.3. Once all the parts are disposed in the cargo configuration, the overall package can be covered with cardboard, plastic or the like to 16 be shipped as cargo having a significantly reduced size.
17 [00131] While the invention has been described in connection with what is 18 presently considered to be the most practical and preferred embodiments, it is to be 19 understood that the invention is not to be limited to the disclosed embodiments and elements, but, to the contrary, is intended to cover various modifications, combinations 21 of features, equivalent arrangements, and equivalent elements included within the spirit 22 and scope of the appended claims. Furthermore, the dimensions of features of various 23 components that may appear on the drawings are not meant to be limiting, and the size 24 of the components therein can vary from the size that may be portrayed in the figures herein. Thus, it is intended that the present invention covers the modifications and 26 variations of the invention, provided they come within the scope of the appended claims 27 and their equivalents.

Claims (50)

What is claimed is:

1. A modular aerodynamic skirt assembly for reducing the air drag of a trailer when installed to the trailer, the modular aerodynamic skirt assembly comprising:
a skirt panel including a plurality of skirt portions; and a plurality of supports for securing the plurality of skirt portions to the trailer in an aerodynamic configuration when the modular skirt panels are secured to the trailer, wherein adjacent skirt portions are connected together with an interconnecting edge disposed at a non-0° angle from vertical when the plurality of skirt portions are operatively secured in the aerodynamic configuration.

2, The modular aerodynamic skirt assembly of claim 1, wherein at least one support is longitudinally located at an interconnecting edge,

3. The modular aerodynamic skirt assembly of claim 1, wherein the non-0° angle is between about 5° and about 15°.

4. The modular aerodynamic skirt assembly of claim 1, wherein the non-0° angle is about 10°,

5. The modular aerodynamic skirt assembly of any one of claims 1 to 4, wherein the interconnecting edge is overlapping two adjacent skirt portions.

6. The modular aerodynamic skirt assembly of any one of claims 1 to 5, wherein the plurality of skirt portions is three skirt portions.

7. The modular aerodynamic skirt assembly of claim 6, wherein the three skirt portions include a front skirt portion, a middle skirt portIon and a rear skirt portion, the middle skirt portion including two interconnecting edges overlapping the adjacent front skirt portion and the adjacent rear portion,

8. The modular aerodynamic skirt assembly of any one of claims 1 to 7;
wherein the three skirt portions are secured together with a series of fasteners.

9. The modular aerodynamic skirt assembly of any one of claims 1 to 8, wherein the interconnecting edge allows progressive mechanical load transfer from one skirt portion to an adjacent skirt portion.

10. The modular aerodynamic skirt assembly of claim 1, wherein a lower portion of the interconnecting edge disposed at a non-0° angle from vertical is defining an obtuse angle with a lower edge of the skirt forming a forward slope with the forward edge of the skirt portion to slip over an external object when the modular aerodynamic skirt assembly is assembled on the trailer in an aerodynamic configuration and the trailer Is moving in a forward direction.

11, A trailer including a modular aerodynamic skirt assembly for reducing the air drag of the trailer, the modular aerodynamic skirt assembly comprising:
a skirt panel including a plurality of skirt portions; and a plurality of supports for securing the plurality of skirt portions to the trailer in an aerodynamic configuration when the modular skirt panels are secured to the trailer, wherein adjacent skirt portions are connected together with an Interconnecting edge disposed at a non-0° angle from vertical when the plurality of skirt portions are operatively secured in the aerodynamic configuration.

12. The trailer of claim 11, wherein at least one support is longitudinally located at an interconnecting edge.

13. The trailer of claim 11, wherein the non-0° angle is about between about 5° and about 15°.

14. The trailer of claim 11, wherein the non-0° angle is about 10°,

15. The trailer of claim 11, wherein the interconnecting edge is overlapping two adjacent skirt portions.

16. The trailer of any one of claims 11 to 15, wherein the plurality of skirt portions is three skirt portions.

17. The trailer of claim 16, wherein the three skirt portions include a front skirt portion, a middle skirt portion and a rear skirt portion, the middle skirt portion including two interconnecting edges overlapping the adjacent front skirt portion and the adjacent rear portion.

18. The trailer of any one of claims 11 to 17, wherein the three skirt portions are secured together with a series of fasteners,

19. The trailer of any one of claims 11 to 18, wherein the interconnecting edge allows progressive mechanical load transfer from one skirt portion to an adjacent skirt portion.

20. The trailer of claim 11, wherein a lower portion of the interconnecting edge disposed at a non-0° angle from vertical is defining an obtuse angle with a lower edge of the skirt forming a forward slope with the forward edge of the skirt portion to slip over an external object when the modular aerodynamic skirt assembly is assembled on the trailer in an aerodynamic configuration and the trailer is moving in a forward direction.

21. A modular aerodynamic skirt assembly for reducing the air drag of a trailer when installed to the trailer, the modular aerodynamic skirt assembly comprising:
a skirt panel adapted to be disposed on a lateral lower side of the trailer, the skirt panel including a plurality of substantially planar skirt portions respectively including a forward edge adapted to be disposed toward a forward portion of the trailer and a trailing edge adapted to be disposed toward a trailing edge of the trailer, the skirt panel being adapted to temporarily bend away from an aerodynamic configuration when contacting an external object and self-recovering the aerodynamic configuration when ceasing contacting the external object; and a plurality of supports for securing the plurality of skirt portions to the trailer in the aerodynamic configuration when the modular skirt panels are secured to the trailer, wherein adjacent skirt portions are interconnected together with an interconnecting edge disposed at a non-0° angle from vertical when the plurality of skirt portions are operatively secured on the trailer in the aerodynamic configuration, the interconnecting edge being configured to provide a progressive longitudinal mechanical load transfer along the skirt panel between adjacent skirt portions when one of the skirt portions is contacting the external object and the skirt panel is temporarily bending away from the aerodynamic configuration.

22. The modular aerodynamic skirt assembly of claim 21, wherein at least one support is longitudinally located at an interconnecting edge.

23. The modular aerodynamic skirt assembly of claim 21, wherein the non-0° angle is between about 5° and about 15°.

24. The modular aerodynamic skirt assembly of claim 21, wherein the non-0° angle is about 10°.

25. The modular aerodynamic skirt assembly of any one of claims 21 to 24, wherein the interconnecting edge of a skirt portion is overlapping a portion of an adjacent skirt portion.

26. The modular aerodynamic skirt assembly of any one of claims 21 to 25, wherein the plurality of skirt portions is three skirt portions.

27. The modular aerodynamic skirt assembly of claim 26, wherein the throe skirt portions include a front skirt portion, a middle skirt portion and a rear skirt portion, the middle skirt portion including two interconnecting edges overlapping the adjacent front skirt portion and the adjacent rear portion.

28. The modular aerodynamic skirt assembly of any one of claims 21 to 27, wherein the three skirt portions are secured together with a series of fasteners.

29. The modular aerodynamic skirt assembly of any one of claims 21 to 28, wherein the interconnecting edge is extending over an overall height of the skirt panel.

30. The modular aerodynamic skirt assembly of claim 21, wherein a lower portion of the interconnecting edge disposed at a non-0° angle from vertical is defining an obtuse angle with a lower edge of the skirt forming a forward slope with the forward edge of the skirt portion to slip over the external object when the modular aerodynamic skirt assembly is assembled on the trailer in an aerodynamic configuration and the trailer is moving in a forward direction.

31. A trailer including a modular aerodynamic skirt assembly for reducing the air drag of the trailer, the modular aerodynamic skirt assembly comprising:
the trailer comprising a skirt panel adapted to be disposed on a lateral lower side of the trailer, the skirt panel including a plurality of substantially planar skirt portions respectively including a forward edge adapted to be disposed toward a forward portion of the trailer and a trailing edge adapted to be disposed toward a trailing edge of the trailer, the skirt panel being adapted to temporarily bend away from an aerodynamic configuration when contacting an external object and self-recovering the aerodynamic configuration when ceasing contacting the external object; and a plurality of supports for securing the plurality of skirt portions to the trailer in the aerodynamic configuration when the modular skirt panels are secured to the trailer, wherein adjacent skirt portions are interconnected together with an interconnecting edge disposed at a non-0° angle from vertical when the plurality of skirt portions are operatively secured on the trailer in the aerodynamic configuration, the interconnecting edge being configured to provide a progressive longitudinal mechanical load transfer along the skirt panel between adjacent skirt portions when one of the skirt portions is contacting the external object and,the skirt panel is temporarily bending away from the aerodynamic configuration.

32. The trailer of claim 81, wherein at least one support is longitudinally located at an interconnecting edge.

33. The trailer of claim 31, wherein the non-0° angle is between about 5° and about 15°.

34. The trailer of claim 31, wherein the non-9° angle is about 10°.

35. The trailer of any one of claims 31 to 34, wherein the interconnecting edge of a skirt portion is overlapping a portion of an adjacent skirt portion.

36. The trailer of any one of claims 31 to 35, wherein the plurality of skirt portions is three skirt portions.

37. The trailer of claim 36, wherein the three skirt portions include a front skirt portion, a middle skirt portion and a rear skirt portion, the middle skirt portion including two interconnecting edges overlapping the adjacent front skirt portion and the adjacent rear portion.

38. The trailer of any one of claims 31 to 37, wherein the three skirt portions are secured together with a series of fasteners.

39. The trailer of any one of claims 31 to 38, wherein the interconnecting edge is extending over an overall height of the skirt panel.

40. The trailer of claim 31, wherein a lower portion of the interconnecting edge disposed at a non-0° angle from vertical is defining an obtuse angle with a lower edge of the skirt forming a forward slope with the forward edge of the skirt portion to slip over the external object when the modular aerodynamic skirt assembly is assembled on the trailer in an aerodynamic configuration and the trailer is moving in a forward direction.

41. A modular aerodynamic skirt kit for reducing the air drag of a trailer when installed to the trailer, the modular aerodynamic skirt assembly comprising:
a skirt panel including a plurality of skirt portions; and a plurality of supports for securing the plurality of skirt portions to the trailer in an aerodynamic configuration when the modular skirt panels are secured to the trailer, wherein adjacent skirt portions are connected together with an interconnecting edge disposed at a non-0° angle from vertical when the plurality of skirt portions are operatively secured in the aerodynamic configuration.

42. The modular aerodynamic skirt kit of claim 41, wherein at least one support is longitudinally located at an interconnecting edge.

43. The modular aerodynamic skirt kit of claim 41, wherein the non-0° angle is between about 5° and about 15°,

44. The modular aerodynamic skirt kit of claim 41, wherein the non-0° angle is about 10°.

45. The modular aerodynamic skirt kit of any one of claims 41 to 44, wherein the interconnecting edge is overlapping two adjacent skirt portions.

46. The modular aerodynamic skirt kit of any one of claims 41 to 45, wherein the plurality of skirt portions is three skirt portions.

47. The modular aerodynamic skirt kit of claim 46, wherein the three skirt portions include a front skirt portion, a middle skirt portion and a rear skirt portion, the middle skirt portion including two interconnecting edges overlapping the adjacent front skirt portion and the adjacent rear portion.

48. The modular aerodynamic skirt kit of any one of claims 41 to 47, wherein the three skirt portions are secured together with a series of fasteners.

49. The modular aerodynamic skirt kit of any one of claims 41 to 48, wherein the interconnecting edge allows progressive mechanical load transfer from one skirt portion to an adjacent skirt portion.

50. The modular aerodynamic skirt kit of claim 41, wherein a lower portion of the interconnecting edge disposed at a non-0° angle from vertical is defining an obtuse angle with a lower edge of the skirt forming a forward slope with the forward edge of the skirt portion to slip over an external object when the modular aerodynamic skirt assembly is assembled on the trailer in an aerodynamic configuration and the trailer is moving in a forward direction,