The present invention concerns a type of freight (load) securing device and system for lashing and securing freight (goods). More specifically, the present invention regards a strap tensioning device (ratchet tie-down) which is so designed that it may be included in an assembly set, with the necessary accompanying tension straps, in accordance with the claims.

Background of the Invention

Every day, large quantities of freight (goods) are moved by various types of vehicles such as, trucks, semi-trailer trucks, tractor-trailers (lorries) and trailers, as well as by ships and barges. This shipping of goods must be carried out in a reliable manner. Certain types of cargo such as sand, concrete and the like can be directly transported by vehicles designed for this type of transportation. For other types of transport, goods must be lashed or tied-down in order for the cargo to be transported. A problem with securing loads in a safe and reliable manner is present when cargo is tied down. Goods that shift during transport may be damaged or cause stability problems with the carrier vehicle, which can lead to accidents. Furthermore, it is not unusual for a load on a transport vehicle to loosen and fall off the vehicle. In the worst case the loosened load may hit surrounding traffic resulting in injuries. The lost cargo if it is hazardous may entail damage to the environment that may be difficult to remedy and very costly to clean up.

Accidents have in several cases been caused by the tensile force in tie-downs around loads decreasing after the cargo has settled or otherwise shifted. This decrease in tensile force is particularly frequent on bumpy roads which cause vibrations and jolts. In order to counter accidents caused by substandard lashing (tie-down) or by cargo settling, government agencies have been placing greater demands on the secure lashing (tie-down) of cargo.

In order to prevent goods from shifting and in the worst case falling off, loads are secured with different types of cargo tie-down (tightening, stretching) devices such as ratchet tie- down (strap) devices. Frequently used cargo tie-down (tightening, stretching) devices basically consist of straps (bands), ropes or chains which are lashed to the load by using different types of tightening (stretching)devices which are usually called tie-downs. A common variant of tie-down which is intended to be used to stretch (tighten) straps (bands) consists essentially of a frame, a lever and a locking device. The lever is via the locking device pivotally arranged in relation to the frame. Thanks to the locking device the strap can be stretched by the lever being moved back and forth.

One problem with existing tie-down devices is that they only stretch on one side of the lashed load. This may mean that the strap is stretched on one side of the load but on the other side is slack. This results in the load being poorly secured and that the cargo after a short distance is likely to loosen so that the load may shift or even fall off the vehicle. It is obvious that there is a need for a tie-down (tensioning) set with which the accompanying straps (bands) can be tensioned so that a substantially constant tension along the entire length of the straps is obtained. Current strap tensioning devices most often only tension (tighten) the strap on one side of the load with a sufficient tension. To be able to tighten (tension) the strap where it is slackest directly during the first lashing would eliminate the need for subsequent tensioning.

Not being confident in that straps are sufficiently taut (stretched) throughout the entire transport means that lashing must be checked regularly during the entire transport. For trucks and trailers, this entails that the vehicle must stop, which increases transportation time and becomes ineffective in the long run. For example, stopping a vehicle on the roadside also increases the driver's risk of injury because he must check the cargo lashing in proximity to traffic and other vehicles often have to reduce their speed for safety reasons when passing a vehicle stopped at the side of the road.

When using tie-downs (ratchet straps) fitted with a hook it may be, for specific types of cargo lashings, difficult or impossible to attach the hook in a reliable manner

Problems with keeping a load securely lashed during transport can also mean that drivers do not secure loads at all because straps do not stay sufficiently taut anyway. Current tie-down (tensioning) devices then become part of the problem and not an effective way to avoid the above mentioned difficulties.

Prior Art

Ratchets for straps are previously known and come in many different types and variations. For example, the international patent application WO2005058639 describes a common type of ratchet tie-down. This ratchet tie-down is of the traditional type, which includes a lever and a frame which are connected via a locking and reeling device. When operating the lever back and forth, the strap is stretched. The design does not include a function with which it can be moved along the length of the strap. Patent document US6195848 describes a ratchet for straps which is intended to be moveable along a straps length. The design differs substantially from the present invention. For example, the design does not include in accordance with patent document US6195848 a first and a second stretching (tightening, tensioning) device. Furthermore the design relies, in accordance with the patent, on the strap being drawn back and forth through the ratchet. The design may not, in a manner similar to the present invention, be moved along part of the strap (band) and be locked in a specific position along the strap's length.

Objectives of the Invention

The main object of the present invention is to achieve a substantially improved tensioning set for securing cargo (goods), which essentially secures cargo in a safer and more reliable manner than existing designs. Another purpose of the present invention is to achieve a tensioning set for securing cargo which includes a first strap tensioning device and a second strap tensioning device. A further purpose of the present invention is to achieve a set of cargo tie-downs (ratchet straps) for securing loads in which at least one strap tensioning device is moveable along the length of the strap. A yet further purpose of the present invention is to create a strap tensioning device with a substantially improved strap control. A further purpose of the present invention is to provide a strap tensioning device which can be used as a traditional strap tensioning device where the strap tensioning device's base member is fixed to at least one strap and that the strap tensioning device if necessary, can be moved variably in relation to strap or straps.

Detailed Description of the Invention

The invention will be described in detail in the following text with reference to the enclosed schematic drawings that show in an exemplifying purpose the current preferred embodiments of the present invention. Figure 1 shows schematically the present invention.

Figure 2 shows a perspective view of the included strap tensioning device. Figure 3 shows the included strap tensioning device from the side. Figure 4 shows an alternative embodiment of the present invention. Figure 5 shows an example of attaching the strap tensioning device. With reference to the figures, and initially Figure 1 , a tie-down assembly set 1 is shown in accordance with the present invention which includes at least a first strap tensioning device 2 and at least a second strap tensioning device 3, and at least a first strap (band) 4. The tie-down assembly may also include at least a second strap (band) 5. In Figures 2 and 3 the strap tensioning devices 2 and 3 are shown in more detail. The strap tensioning device consists mainly, in its basic design, of some variant of a previously known design of a strap tensioning device which has been modified with a strap guide (band guide) 6 and in alternative embodiments with at least one strap lock (band lock) in accordance with the present invention. Strap tensioning device 2 and strap tensioning device 3 mainly consist of a base member 7, a lever (handle) 8 and a locking device 9. The lever 8 is pivotally attached to the base member 7 via an axel-like reel member 10 included in the locking device 9.

The base member 7 includes a first pair of arms, consisting of arms 11 and 12 and at least one strap holder 13. The first pair of arms (wings) 11 and 12 are preferably designed to be parallel at the respective opposite sides of the base member and perpendicular to the base member. In alternative embodiments the arms (wings) for all or part of their length may deviate from being parallel. Each of the first pair of arm (wing) 11 and arm (wing) 12 includes a through hole (swing hole) 14 and at least one radial slot 15. The radial slot 15 is defined by the first wing near the through hole 14 along an extended radius of the through hole 14. The base member 7 is preferably made from a metal material such as steel of adequate quality for the purpose. It is conceivable that the base member be made of another suitable material for the purpose or a combination of materials suitable for the purpose.

Lever 8 includes a second pair of arms. The second pair of arms is comprised of a first arm 16 and a second arm 17. The arms 16 and 17 are preferably parallel with each other and equipped with a through hole (swing hole) 18 at one end. The through hole 18 in the lever is used in conjunction with hole 14 in the base member together with the reel 10 in connecting lever 8 with the base member 7. The base member 7 and the lever 8, are thus pivotally arranged around a common rotational center. Lever 8 further includes at least one transverse axel 19 between the arms linking the arms with each other. In alternative embodiments the lever may include at least two transverse axels. One of the transverse axels, is preferably a grip 20 with which the lever 8 can be operated. Lever 8 is preferably made from a metal material of for example such a steel quality as appropriate for the purpose. Alternatively, another suitable material for the purpose may be selected for the lever. Each strap tensioning device includes a function for reeling (retracting, rolling-up) the strap. This feature consists of a reel 10 which forms a part of the locking device 9. This locking device 9 allows the strap to be tensioned (stretched) and also for the strap, after it has been tensioned, to remain in a tensioned position. The locking device 9 will usually include at least two ratchet wheels 21, a reel 10 such as a spool (cylinder). The reel 10 which is used to roll- up the strap is preferably comprised of two fulcrum pins 22 and 23 with an intermediate and through space 24. This design could also include distance members (spreaders, spacers) 25 which separate fulcrum pins 22 and 23. A series of teeth are spaced around the periphery of the ratchet wheel 21. A through hole 26 is further defined in each ratchet wheel. The through hole 14 in the first arm pair (wings), and the through hole 18 in the second arm pair (wings) and the holes in the ratchet wheels are in line with each other. At least one ratchet wheel is mounted between the corresponding first and second arms (wings). Fulcrum pins 22 and 23 pass through the through holes, and the ratchet wheels 21 are mounted on the fulcrum pins.

A locking member in the form of a locking plate 27 is moveably mounted in the grooves 28 in the first pair of wings in the base member. A second locking member in the form of a locking plate is also moveably mounted in the grooves (slots) in the second arm pair included in the lever. Locking plate 27 includes preferably two protrusions, whose first part runs in the groove in the one arm and the second protrusion runs in the groove in the other arm. The protrusions are designed to be moved along the length of the groove. The base member includes an attachment 29, rest or similar for at least one spring 30. The locking plate is affected by the spring force from the spring 30 to move in the direction of the ratchet wheels 21 (gears). By this spring force the locking plate 27 is forced to interlock with the cogs of the ratchet wheels 21 (gears). Ratchet wheels 21 are designed so that the locking member locks against the cogs in the one direction and that locking member glides over the cogs in the other direction.

The locking device 9 allows the strap to be rolled onto the reel when the lever 8 is operated in the one direction as shown by arrow 31. The locking device prevents the tensioned strap from loosening when operating the lever in the opposite direction as shown by arrow 32. In the opposite direction the lever 8 can be freely returned with the reel in the locked position. The locked position leads to the reel (spool) being prevented to rotate in the one direction and that the strap is prevented from being rolled up by the reel. The design includes a grip 33 or the like with which the locking plate may be released during the unlashing of the load. The grip may be made up of the plate (locking member) itself. What is unique with the present invention is that the base member 7 of the strap tensioning device includes a strap guide (band guide) 6 which functions to control the strap and position the strap tensioning device relative the strap. In the present design, this is achieved by the base member 7 being equipped with a first axel 34 and a second axel 35. The first axel 34 or the second axel 35 can be made up of, in known designs, existing strap holders (strap attatchments) 13. The first axel 34 runs between the arms (wings) in the first arm pair. The second axel 35 also runs between the arms (wings) on the first arm pair. The angle between the first axel 34 and the second axel 35 in relation to the strap's and base member's axial direction is preferably between 10 to 45 degrees. The distance between the first and second axel is adjusted to the intended strap thickness. Preferably the distance between the first and the second axel must be at least twice the strap thickness and preferably between six to twelve times the strap thickness.

The design may, in alternative embodiments, also include a function with which the strap tensioner's base member may be temporarily fixed to the strap. The tie-down assembly set (1) may also for example include a storage reeling device for storing the strap and strap tensioner.

In Figure 5 is shown a strap tensioning device 2 equipped with a strap whose one end is connected to the strap tensioning device's first axel. The strap tensioning devices second axel is fitted with an attachment member that in the figure consists of a hook. The design allows the strap tensioning device to be connected to an object by the straps being drawn around (over) the object and by the attachment member (hook) being attached to (hooked to) the strap tensioning device's second axel. If the attachment member consists of a loop (eye, ring) in the strap, the loop may be attached to the strap tensioning device's second axel. This can be accomplished by the second axel being slidable in its axial direction (so that the axel is released from the first wing or the second wing). First, the axel is slid so that the loop can be attached at one end of the second axel after which the axel (after the loop is attached to the axel) is reattached and fixed to a position where the loop can not be detached from the second axel.

Utilizing Examples of the Present Invention

In the following text an example of use of the tie-down set assembly in accordance with a preferred embodiment of the present invention will be described in more detail. In the preferred embodiment the cargo tie-down set assembly is comprised of a first strap tensioning device 2, a second strap tensioning device 3, a first strap 4 and a second strap 5. When using the preferred embodiment, the one end 36 of the first strap 4 is attached in the usual manner with an attachment member (fastener, hook or similar) 37 to an anchorage point on a vehicle (vessel) 38 (shown illustratively) such as a trailer, truck, boat, barge or similar. The strap 4 (the first strap) is inserted between the first axel 34 and the second axel 35 of the first strap tensioning device 2 and further in between the fulcrum pins 22 and 23 in the reel 10. The strap is then drawn over the load (goods, cargo) 39 and is connected in the usual manner to the second strap tensioning device 3 by the straps other end being inserted in between the fulcrum pins 22 and 23 in the reel in the second strap tensioning device 3. The second strap tensioning device 3 is one of the axles 34 or 35 securely connected to one end of the second strap 5. The second strap is attached with at least one attachment member (fastener, hook or similar) 40 to an anchorage point or similar on the vehicle (vessel) 38. The first strap 4 and the second strap 5 are tensioned so that they are not slack. Then the lever (handle) 8 on the second strap tensioning device 3 is operated back and forth until an appropriate strap tension for the purpose is achieved in the straps 4 and 5. The first strap tensioning device 2 may then be used to adjust the tension in the straps by its handle being operated back and forth by which an increased strap tension is achieved in the first respective second strap. By this procedure, slack on either side of the load is minimized.

In an alternative embodiment, as shown in Figure 4, it is conceivable that the cargo tie-down set assembly, in accordance with the present invention, is comprised of a first strap tensioning device 2, a second strap tensioning device 3 and only a first strap 4. When using the alternative embodiment, the one end 36 of the first strap 4 is attached in the usual manner with an attachment member 37 to an anchorage point on a vehicle 38 such as a trailer, truck or similar. The strap 4 (first strap) is inserted between the first axel 34 and the second axel 35 in the first strap tensioning device 2 and further in between the fulcrum pins 22 and 23 in the reel 10. The straps (bands) are then drawn over (around) the load 39 and is connected to the other strap tensioning device 3 by the strap's other end being inserted in between the fulcrum pins 22 and 23 in the reel in the second strap tensioning device and further in between the first axel 34 and the second axel 35. An attachment member 40 at the other end 41 of the strap 4 can then be attached to an anchorage point on the vehicle (vessel) 38 such as a trailer, truck, boat, barge or similar. Both the first strap tensioning device 2 and the second strap tensioning device 3 are by this design freely movable along the length of the first strap 4. The design assumes that one of the straps attachment members can be inserted in between the fulcrum pins 22 and 23. This can be accomplished if the attachment member consists of a loop in the strap. The design is possible if the first and the second strap tensioning device 2 and 3 are separable.

In the detailed description of the present invention, design details may have been omitted which are obvious to a specialist in the field, such obvious design features are included to the extent necessary for achieving an adequate function of the present invention.

Even if some preferred embodiments have been described in detail, different alternatives and modifications within the scope of the invention will be apparent to persons skilled in the art and all those are deemed to fall within the scope of subsequent patent claims. For example, it is conceivable that at least one strap tensioning device be designed to be separable so that the strap (one of the straps) may be inserted into the reel without the need for the strap to be loosened.

Advantages of the Invention

The main advantage of the present invention is to achieve a substantially improved tie-down set assembly which allows for a considerably improved securing (lashing) of loads than previously known designs. A further advantage of the present invention is to achieve a strap tensioning device which can be temporarily moved along the length of the strap length and be temporarily locked to the strap.