SE540386C2 - Tensioning strap for fasting a container to a vehicle - Google Patents

Abstract

A tensioning strap (8) adapted to at least partly surround and fasten a container (4) to a body (2) of a vehicle. The tensioning strap (8) comprises an opening (19), through which an engagement element (20) is adapted to extend for fasten the tensioning strap (8) to the body (2). The opening (19) has an semi-elliptical or elliptical longitudinal section shape.

Description

Tensioning strap for fasten a container to a vehicle TECHNICAL FIELD The present invention relates to a tensioning strap adapted to fasten a container to a vehicle, an attachment assembly comprising a tensioning strap and a vehicle comprising an attachment assembly.

BACKGROUND Vehicles, such as trucks, may comprise a fuel tank. The fuel tank may be fastened to the body of the vehicle, such as on a chassis beam, by means of elongated tensioning straps adapted to embrace the tank. Also other tanks and containers may be fastened to the body in a similar way. The tensioning straps may comprise openings at their respective ends. A pin may extend through each opening. The pin may be arranged to co-operate with corresponding fasteners, holes in holder profiles etc. on the body. When the tensioning strap is tensioned the strain in the material around the opening may depend on the size of the opening and the size of the pin. If the opening is to large relative to the pin the material around the opening will bend around the pin during a tensioning procedure which can give rise to excessive strain at the end of the tensioning strap being in engagement with the body. In serious cases such excessive strain might results in formation of cracks at the tensioning strap. If the opening on the other hand is smaller the strain may be reduced but it may instead be more difficult and less ergonomic to insert the pin in the opening during assembly. Improvements in the field of tensioning straps for fasten a container to a vehicle are therefore desirable.

SUMMARY An object of the present invention is to address and at least alleviate the above mentioned problems. A further object is to improve the durability of a tensioning strap.

In accordance with the present invention, there is provided a tensioning strap adapted to at least partly surround and fasten a container to a body of a vehicle. The tensioning strap comprises an opening, through which an engagement element is adapted to extend for fasten the tensioning strap to the body. The opening has, in a non-tensioned state a semi-elliptical or elliptical longitudinal section shape converging towards a vertex over a minimum distance exceeding the radius of the engagement element adapted to extend through the opening.

Ellipses have two perpendicular axis about which the ellipse is symmetric. Due to this symmetry, the axis intersect at the center of the ellipse. The larger of the two axis, the major axis, corresponds to the larger distance between antipodal points of the ellipse. The smaller of the two axis, the minor axis, corresponds to the smaller distance between antipodal points of the ellipse. The four points where the axis cross the ellipse are vertexes. In addition to being the largest and the smallest distance from the center these points are where the curvature of the ellipse is at its maximum and at its minimum. A semi-ellipse have the shape of half of an ellipse bisected by one of its axis. The semi-ellipse may have a minor axis as the ellipse but only one half of the major axis which is a semi-major axis. The semi-major axis extends from the center of the ellipse to a point where the curvature of the ellipse is at its minimum. During assembly the engagement element is inserted into the opening which has a semi-elliptical or elliptical longitudinal section shape. The engagement element is inserted at the center where the distance between the vertexes is largest and the curvature of the ellipse is at its maximum, which facilitates the insertion of the engagement element in the opening. During a tensioning procedure the engagement element is brought into abutment against a point where the curvature of the ellipse is at its minimum, which results in a relatively good fit between the engagement element and the curvature of the ellipse, which in turn results in that excessive strain in the tensioning strap is eliminated or at least reduced and that the durability of the tensioning strap is improved.

According to an optional aspect of the invention the semi-ellipse or the ellipse has a minor axis, the minor axis passes through a first inner surface at a first co-vertex and through a second inner surface at a second co-vertex. The distance along the minor axis between the first inner surface and the second inner surface is in the range 13-23 mm. An opening with a minor axis according to the range has proven to be able to accommodate an engagement element whose diameter is great enough to provide secure load reception and at the same time facilitate the insertion of the engagement element in the opening.

According to an optional aspect of the invention the semi-ellipse or the ellipse has a semimajor axis, the semi-major axis passes through a third inner surface at a vertex. The third inner surface having a first radius, the first radius is in the range 5,5-10,5 mm. An opening with a first radius according to the range has proven to be able to accommodate an engagement element whose diameter is great enough to provide secure load reception and at the same time provide a relatively good fit between the engagement element and the curvature of the ellipse.

According to an optional aspect of the invention the tensioning strap comprises at least one end bent into a loop, the loop delimits the opening. The end bent into a loop is guided on the tensioning strap and fasten to the tensioning strap by fastening means. Hereby the semielliptical or elliptical shape may be achieved in a relatively simple manner.

According to an optional aspect of the invention tensioning means is arranged along the tensioning strap. Hereby the tensioning strap may be tensioned in a relatively simple manner.

In accordance with the present invention there is also provided an attachment assembly comprising a tensioning strap adapted to at least partly surround and fasten a container to a body of a vehicle and an engagement element for fasten the tensioning strap to the body, the tensioning strap comprises an opening with a semi-elliptical or elliptical longitudinal section shape according to what is mentioned above. According to some embodiments the engagement element is a pin. A pin is an easily accessible standard component which has proven to be suitable to use in connection with tensioning straps.

According to an optional aspect of the invention the engagement element has a second radius, the second radius is in the range 5,5-10 mm. According to some embodiments the semi-ellipse or the ellipse has a semi-major axis, the semi-major axis passes through a third inner surface at a vertex, the third inner surface having a first radius whereby first radius = second radius i.e. the first radius is equal or substantially equal to the second radius. Since the first radius and the second radius are equal or substantially equal a relatively good fit is provided between the engagement element and the curvature of the ellipse which results in that excessive strain in the tensioning strap is eliminated or at least reduced and that the durability of the tensioning strap is improved. Further, since there is a relatively good fit provided between the engagement element and the curvature wrapped around the element there is relatively little friction between the element and the curvature during a tensioning procedure. This may allow a predetermined tensioning force of only at least 100 N.

According to an optional aspect of the invention the semi-ellipse or the ellipse has a semimajor axis, the semi-major axis passes through a third inner surface at a vertex, the third inner surface having a first radius whereby first radius < second radius i.e. slightly smaller than the second radius. During a tensioning procedure the third inner surface is brought closer to the engagement element, and the engagement element is brought into abutment against an inner contour of the semi-ellipse/ellipse at a distance from the third inner surface. During a continued procedure the third inner surface is brought into abutment against the engagement element while the contour is sliding on, and is formed by the engagement element which may require a predetermined tensioning force of at least 1,5 KN. Since there is a sliding movement between the contour and the engagement element and not a bending movement the excessive strain is eliminated or at least reduced despite that the first radius is less than the second radius.

According to an optional aspect of the invention the first radius is in the range 0,65-0,95 times the second radius. An opening with a first radius according to the range has proven to be able to accommodate an engagement element whose diameter is great enough to provide secure load reception while allowing a sliding movement between contour of the ellipse and the engagement element.

In accordance with the present invention there is also provided a vehicle comprising an attachment assembly according to what is mentioned above.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and are intended to provide further explanation of the invention as claimed. Further features of, and advantages with, the present invention will become apparent when studying the appended claims and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in greater detail with reference to the accompanying drawings in which: Fig. 1 is a side view of a vehicle having a body and a container fastened to the body.

Fig. 2 is an end view of the container and an attachment assembly for the container.

Fig. 3 is a perspective view of a part of the attachment assembly.

Fig. 4 is a longitudinal section in the plane A-A in fig. 3, of a conventional tensioning strap for the container, before the tensioning strap is tensioned.

Fig. 5 is a longitudinal section in the plane A-A in fig. 3, of a conventional tensioning strap for the container, after the tensioning strap has been tensioned.

Fig. 6 is a longitudinal section in the plane A-A in fig. 3, of an improved tensioning strap for the container according to some embodiments, before the tensioning strap is tensioned.

Fig. 7 is a longitudinal section in the plane A-A in fig. 3, of an improved tensioning strap for the container according to some embodiments, after the tensioning strap has been tensioned.

Fig. 8 is a longitudinal section in the plane A-A in fig. 3, of an improved tensioning strap for the container according to some embodiments, before the tensioning strap is tensioned.

Fig. 9 is a longitudinal section in the plane A-A in fig. 3, of an improved tensioning strap for the container according to some embodiments, during a tensioning procedure.

DETAILED DESCRIPTION The invention will now be described with reference to the drawings in which some exemplary embodiment are shown. Well-known functions or constructions will not necessarily be described in detail for brevity and/or clarity.

Fig. 1 shows a side view of a vehicle 1 having a body 2 comprising a chassis beam 3. A container 4 is fastened to the body 2 by means of two attachment assemblies 5. The vehicle 1 may be a truck. The container 4 may be a fuel tank.

Fig. 2 shows an embodiment among others of an attachment assembly 5. The attachment assembly 5 may comprise an attachment devise 6 which at its one end is attached to a first end 7 being an end loop of a tensioning strap 8. Its other end is attached to the body 2 via a connector 9 fastened to the chassis beam 3. The tensioning strap 8 is adapted to at least partly surround and fasten the container 4 to the body 2. The tensioning strap 8 may be band-shaped. The tensioning strap 8 may be made of metal, preferably steel. The container 4 may rest on a generally L-shaped holding device 11. The connector 9 may be a stand-alone part or an integrated part of the holding device 11. A second end 12 being an end loop of the tensioning strap 8 and arranged opposite to the first end 7 is attached to a free shank end 13 of the holding device 11. Tensioning means 14 may be arranged along the tensioning strap 8 with the aid of which the tensioning strap 8 may be tensioned and the container 4 may be forced against a bearing surface 15 on the holding device 11. At an embodiment the tensioning means 14 may be provided between the first end 7 and the second end 12. At an embodiment the tensioning means 14 may be provided at the first end 7. At a further embodiment the tensioning means 14 may be provided at the second end 12.

There may be a slight deviation between a direction of an imagined plane 16 through the attachment device 6 and the direction of an upper surface 17 of the container 4 when the container 4 is mounted on the vehicle. The cause of the deviation is that the fixing point in the connector 9 for the attachment device 6 may be positioned slightly below the upper surface 17 in order to provide a downwards directed holding force when the tensioning means 14 is activated for tensioning the tensioning strap 8. According to an embodiment the first end 7 may be attached to body 2 via the connector 9 without any intermediate attachment device 6. In that case the direction of the imagined plan 16 is through the first end 7. Irrespective this slight deviation or if the attachment device 6 is used or not, forces affecting the tensioning strap 8 when the tensioning means 14 is activated acts essentially in the longitudinal direction 18 of the tensioning strap 8.

As can be seen in fig. 2 the first end 7 and the second end 12 of the tensioning strap 8 comprises a respective opening 19 through which a respective engagement element 20 is adapted to extend for fasten the tensioning strap 8 to the body. As can be seen in greater detail in fig. 3 at least one end, in the example the first end 7, is bent into a loop. The loop delimits the opening 19 and is adapted to enclose the engagement element 20. The engagement element 20 may be arranged in a direction perpendicular to the longitudinal direction 18 (fig. 2) of the tensioning strap 8. The engagement element 20 may have a cylindrical cross-section. The engagement element 20 may be a pin, preferably a clevis pin and fits into bores 21 in a U-shaped first part 22 of the attachment device 6. At an embodiment, the end bent into a loop, in the example the first end 7, is guided on the tensioning strap 8 and fastened to the tensioning strap 8 by fastening means 24. At an opposite end of the attachment device 6, a second part 27 is situated. The second part 27 comprises a bore in parallel to the bores in the first part 22. This bore is adapted to receive a pin 28, preferably a clevis pin, having a length to extend outside the width of the second part 27 and with portions close to its end to cooperate with bores 29 in a U-shaped portion of the holing device 11 and/or with the connector 9 which may be arranged inside the holding device 11 so as to fix the attachment devices 6 to the body 2. Between the first part 22 and the second part 27 there is an intermediate part 30 which may have an elongated form. At an embodiment without the attachment device 6 the first end 7 may be adapted to extend into the U-shaped portion and the engagement element 20 may be arranged to co-operate with the bores 29.

Fig. 4 shows a longitudinal section in the plane A-A in fig. 3, of a conventional tensioning strap 8 before it is tensioned. The opening 19’ has a drop-shaped longitudinal section shape and comprises a semi-circular section 33 adapted to receive the engagement element 20. The engagement element 20 has a third radius 34 and the semi-circular section 33 has an inner surface with a fourth radius 35. The fourth radius 35 is greater than the third radius 34 and the reason for this is to facilitate the insertion of the engagement element 20 into the opening 19’ during assembly. Since the fourth radius 35 is greater than the third radius 34 there is a gap 36 between the engagement element 20 and the inner wall of the opening 19’ before tensioning the tensioning strap 8. During a tensioning procedure the tensioning means 14 (fig. 2) is activated and a tensioning force is applied to the tensioning strap 8 in its longitudinal direction 18. Initially the inner surface of the opening 19’ is brought into abutment against the engagement element 20, as can be seen in fig. 5 but there are still gaps 36 between the engagement element 20 and the inner surface of the opening 19’ at the ends 37 of the semicircular portion 33. During a continued procedure the ends 37 will bend around the engagement element 20 and the tensioning strap 8 reaches the position marked with dashed lines in fig.5. The bending may give rise to excessive tensile strain at the end of the tensioning strap 8 and particularly at the semi-circular portion 33. This strain is symbolized with a double arrow in the figure.

Fig 6 shows a longitudinal section in the plane A-A in fig. 3, of an improved tensioning strap 8 in a non-tensioned state . The opening 19 may have a semi-elliptical longitudinal section shape bisected by a minor axis 40. The semi-ellipse is shown by solid lines in the figure. At some embodiments the opening 19 may have an elliptical longitudinal section shape, which is shown by dashed lines. Both the semi-ellipse and the ellipse have, in addition to the minor axis 40, a center 48, a semi-major axis 41, a vertex 42, a first co-vertex 43 and a second covertex 44. The minor axis 40 passes through a first inner surface 45 at the first co-vertex 43 and through a second inner surface 46 at the second co-vertex 44. The first- and the second inner surface 45,46 each are in the shape of an arc. The semi-major axis 41 passes through a third inner surface 47 at the vertex 42. The third inner surface 47 is in the shape of an arc having a first radius R1. The distance along the minor axis 40 between the first inner surface 45 and the second inner surface 46 is greater than the diameter of the engagement element 20 adapted to be inserted in the opening 19. The distance may e.g. be in the range 13-23 mm. At some embodiments the distance is at least 16 mm. At some embodiments the distance is at least 18 mm. At some embodiments the distance is at least 20 mm. The engagement element 20 has a second radius R2. At some embodiments the first radius R1 may be equal to or less than the second radius R2, thus, first radius R1 At some embodiments the first radius R1 and the second radius R2 may be equal i.e. first radius R1=second radius R2. The first radius R1 and the second radius R2 may e.g. be in the range 5,5 - 10,5 mm. At some embodiments the first radius R1 and the second radius R2 is at least 7 mm. At some embodiments the first radius R1 and the second radius R2 is at least 8 mm. At some embodiments the first radius R1 and the second radius R2 is at least 9 mm.

At some embodiments the first radius R1 may be less than the second radius R2 i.e. first radius R1< second radius R2. R1 may be in the range 0,65-0,95 times the second radius R2. At some embodiments R1 is at least 0,7 times the second radius R2. At some embodiments R1 is at least 0,8 times the second radius R2. At some embodiments R1 is at least 0,9 times the second radius R2.

Fig. 6 shows an embodiment in which the first radius R1 and the second radius R2 is equal During assembly the engagement element 20 is inserted into the opening 19 between the first inner surface 45 and the second inner surface 46 at the center 48 of the semi-ellipse/ellipse. Since the distance between the first inner surface 45 and the second inner surface 46 is greater than the diameter of the engagement element 20 the insertion is facilitated. During a tensioning procedure the tensioning means 14 (fig. 2) is activated and a tensioning force is applied to the tensioning strap 8 in its longitudinal direction. Initially the third inner surface 47 is brought into abutment against the engagement element 20, as can be seen in fig. 7. Since the first radius R1 and the second radius R2 are equal there is a relatively good fit between the engagement element 20 and the first inner surface 47 which results in that, during a continued procedure, the bending of the ends 37 discussed in relation to fig 4 is eliminated and that the excessive strain therefore is eliminated or at least reduced.

Fig. 8 shows an embodiment in which the first radius R1 is less than the second radius R2. During assembly the engagement element 20 is inserted into the opening 19 between the first inner surface 45 and the second inner surface 46 as described in relation to fig. 6. During a tensioning procedure the third inner surface 47 is brought closer to the engagement element 20, as can be seen in fig. 9 and the engagement element 20 is brought into abutments against an inner contour 49 of the semi-ellipse/ellipse. During a continued procedure the third inner surface 47 is brought into abutment against the engagement element 20 while the contour 49 is sliding on, and is formed by the engagement element 20. The bending of the ends 37 discussed in relation to fig 4 is eliminated and the excessive strain is therefore eliminated or at least reduced.

The vehicle 1 is described as a truck but it may for example be a bus. The vehicle 1 may be any commercial vehicle or any constructional vehicle or the like. Further the vehicle 1 may be a semitrailer or a trailer etc. The container 4 is described as a fuel tank but it may for example be a hybrid battery container for a battery or batteries for hybrid operation of a hybrid vehicle. At another embodiment, the container may for example be a gas pressure tank or a package of tanks to be used in a vehicle driven with compressed natural gas (CNG). At a further embodiment, the container may be a silencer. At another embodiment, the container 4 may be an auxiliary container which basically can be any other type of container to be fastened to a vehicle.

Two attachment assemblies are illustrated in fig.1. The dimensions and the numbers of the attachment assemblies may however be varied according to the requirements in respect of expected loads and available space. Further, each attachment assembly may also be referred to as a vehicle container attachment assembly, an attachment arrangement or a vehicle container attachment arrangement.

Although the invention has been explained in relation to its preferred embodiments as mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the present invention. It is therefore contemplated that the appended claims will cover such modifications and variations that fall within the true scope of the invention.

Claims (13)

1. A tensioning strap adapted to at least partly surround and fasten a container (4) to a body (2) of a vehicle (1), the tensioning strap (8) comprises an opening (19), through which an engagement element (20) is adapted to extend for fasten the tensioning strap (8) to the body (2), characterized in that the opening (19), in a non-tensioned state has a semi-elliptical or elliptical longitudinal section shape converging towards a vertex (42) over a minimum distance exceeding the radius (R2) of the engagement element (20) adapted to extend through the opening (19).

2. A tensioning strap according to claim 1, characterized in that the semi-ellipse or the ellipse has a minor axis (40), the minor axis (40) passes through a first inner surface (45) at a first co-vertex (43) and through a second inner surface (46) at a second co-vertex (44) whereby the distance along the minor axis (40) between the first inner surface (45) and the second inner surface (26) is in the range 13-23 mm.

3. A tensioning strap according to claim 1 or 2, characterized in that the semi-ellipse or the ellipse has a semi-major axis (41), the semi-major axis (41) passes through a third inner surface (47) at the vertex (42), the third inner surface (47) having a first radius (R1), the first radius (R1) is in the range 5,5-10,5 mm.

4. A tensioning strap according to any one of claims 1-3, characterized in that the tensioning strap (8) comprises at least one end (7) bent into a loop and that the loop delimits the opening (19).

5. A tensioning strap according to claim 4, characterized in that the end (7) bent into a loop is guided on the tensioning strap (8) and fasten to the tensioning strap (8) by fastening means (24).

6. A tensioning strap according to claim 1, characterized in that tensioning means (14) is arranged along the tensioning strap (8).

7. An attachment assembly comprising a tensioning strap (8) adapted to at least partly surround and fasten a container (4) to a body (2) of a vehicle (1) and an engagement element (20) for fasten the tensioning strap (8) to the body (2), characterized in that the tensioning strap (8) comprises an opening (19) with a semi-elliptical or elliptical longitudinal section shape according to any one of claims 1-6.

8. An attachment assembly according to claim 7, characterized in that the engagement element (20) is a pin.

9. An attachment assembly according to claim 7 or 8, characterized in that the engagement element (20) has a second radius (R2), the second radius (R2) is in the range 5,5-10 mm.

10. An attachment assembly according to any one of claims 7-9, characterized in that the semi-ellipse or the ellipse has a semi-major axis (41), the semi-major axis (41) passes through a third inner surface (47) at a vertex (42), the third inner surface having a first radius (R1) whereby first radius (R1) = second radius (R2).

11. An attachment assembly according to any one of claims 7-9, characterized in that the semi-ellipse or the ellipse has a semi-major axis (41), the semi-major axis (41) passes through a third inner surface (47) at a vertex (42), the third inner surface having a first radius (R1) whereby first radius (R1) < second radius (R2).

12. An attachment assembly according to claim 11, characterized in that the first radius (R1) is in the range 0,65-0,95 times the second radius (R2).

13. A vehicle comprising an attachment assembly according any one of claims 7-12.