HK1247165B - Load-strapping device - Google Patents

Description

Load strapping device

Technical Field

The present invention relates to a load lashing device for securing a load to a vehicle, in particular a trailer or a truck. The device is configured to connect and tighten a strap for holding a load on a platform or other load-bearing base.

Background Art

A prior art load strapping device features a shaft extending between flanges of the device's pivoting frame sections. The free end of the strap passes through a slot in the shaft, and a pawl and ratchet mechanism provided at the connection rotates the shaft in one direction, causing the strap to wrap around the shaft as the frame sections repeatedly pivot in the opposite direction. The strap is released by pulling two locking pawls, one in each frame section, against a spring bias, releasing the ratchets, allowing the shaft to rotate backward and unwind the strap. The free end of the strap can then be pulled out of the slot. This prior art requires some tedious work in handling the sometimes long free end of the strap and pulling it through the slot before tightening it, as well as the reverse process of unwinding the strap end and finally pulling it out again. For large loads requiring multiple straps, these actions must be repeated multiple times.

US2008/0244883A1 discloses a strapping device with a two-part shaft. A first shaft part can be moved relative to a second shaft part to engage and/or release a strap between the shaft parts. The movement between the shaft parts for engaging and releasing the strap is transverse, allowing one shaft part to slide parallel to the other shaft part, thereby exposing the space in which the strap is to be positioned. Thus, the strap can be placed in the exposed space without having to use and pull the end of the strap through a slot in the shaft. After positioning the strap, the slot is established by sliding the other shaft part back into the operating or closed position. Release of the strap after deployment is facilitated by reversing the movement of the movable shaft part. Similar designs are disclosed in WO2007/113373 and WO2012/095551.

WO2006/001714 discloses a strapping device with a bifurcated shaft. In one embodiment, the shaft is provided with two parallel arms connected by a bend. In the installed condition, the parallel arms form a slot in the shaft. The shaft can be inserted and removed laterally in the connection between the movable parts. This allows the strap to be installed and removed without grasping the free end of the strap and pulling it through the slot. Release can be achieved by pulling the shaft laterally, allowing the strap coils to slide off the shaft.

The prior art disclosed in the cited documents all require manipulation of a portion of the shaft to engage and disengage the strap. In outdoor conditions, operation can be hampered when using gloves for protection, slippery surfaces caused by rain or ice, and dirt on the strap, particularly when disengaging and releasing the strap from the strapping device.

Summary of the Invention

In a preferred embodiment, the present invention provides a load strapping device comprising at least two frame parts connected by a pivotable connection, wherein one of the frame parts is attached to a strap, wherein the connection between the pivotable parts is provided with a shaft extending between parallel flanges of the frame parts, the pivotable connection between the pivotable parts being provided with a pawl and ratchet mechanism at opposite ends of the shaft, the pawl and ratchet mechanism providing one-way rotation of the shaft when the pivotable base parts are repeatedly pivoted in opposite directions, wherein the shaft is provided with at least one groove cut into the body of the shaft, wherein the at least one groove is adapted to receive the strap.

In a further advantageous embodiment of the invention, the shaft is provided with two grooves which are arranged at respectively different angles of inclination relative to the axis of rotation of the shaft and which are spaced apart from one another and are in opposite orientations.

In these embodiments, no moving parts are required to maintain the strap in a fixed relationship with the shaft. In this context, fixed relationship should be understood as meaning that the strap does not guide the shaft as the shaft rotates, but rather wraps around it. The very simple feature of providing a groove in the shaft into which the strap is inserted creates a simple, maintenance-free, and extremely reliable clamping device that is easy to use and does not require any special tools or handling for operation. Naturally, the strap must be sufficiently flexible to enable insertion into the groove, but for the equally common stiffer straps, the shaft will be longer, allowing for a greater distance between the grooves, so that the strap does not need to bend or deform significantly in order to be inserted into the grooves.

In a further advantageous embodiment of the invention, the grooves are cutouts which are arranged symmetrically at a predetermined distance around the center of the shaft, wherein the openings of the grooves are closer to the center than the bottoms of the grooves.

The cutouts can be easily provided by suitable machinery and by maintaining a predetermined distance and having the cutouts be of a certain size, for example 150% of the thickness of the strap which the groove is to receive, placing the strap in the groove becomes very easy and the shaft becomes relatively cheap to manufacture.

Naturally, the shaft could be manufactured to an oversized size to accommodate the groove, but generally the material properties of the steel from which the shaft is manufactured are sufficient so that the groove does not weaken the construction to the extent that the shaft becomes a weak point in the construction.

The grooves are arranged so that they flare outwards, i.e. so that the openings of the grooves are closer to each other than the bottoms of the grooves, whereby by bending the strap the two side edges will fit into the grooves in the shaft. The mutual distance between the grooves, in particular the mutual distance between the openings of the grooves, will be set according to the width and suitability of the strap for which the load strapping device is designed.

In a further advantageous embodiment of the invention, the grooves are connected to an enlarged cutout portion which spans the diameter of the shaft and has an extension in the longitudinal direction of the shaft along the axis of rotation, which extension intersects at least two grooves.

The enlarged cutout is designed to accommodate the brace, with the groove allowing the brace to enter the enlarged cutout. Once the brace is in the enlarged cutout, the side edges of the brace will spread out in the enlarged cutout, preventing the brace from bending. As a result, when the brace is wound around the shaft, the brace will be smoother, allowing for easier winding/unwinding, while also allowing for more windings because the windings are completely flat.

A guide element may be provided on the shaft or as part of the shaft, wherein the guide element is adapted to guide the insertion of the brace through the groove, thereby ensuring a secure winding of the brace.

The invention also relates to a method for using the device according to the invention, comprising the following method, wherein a device is selected having a shaft with a width that at least corresponds to the width of the brace to be strapped, and wherein the brace is arranged flat on the shaft, after which the side edges of the brace are inserted into corresponding grooves provided in the shaft, after which the ratchet mechanism is actuated to wind the brace around the shaft, thereby tightening the brace.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, in which:

FIG1 shows a perspective view of a prior art embodiment of a load strapping device;

FIG2 shows an embodiment of the present invention without a strap installed in the shaft;

FIG3 shows an embodiment of the present invention with a strap installed in the shaft;

FIG4 shows another embodiment of the present invention;

FIG5 shows another embodiment of the present invention;

FIG6 shows the embodiment of FIG5 with the strap installed in the shaft; and

7A and 7B show an example where a guide element has been provided to guide the brace.

DETAILED DESCRIPTION

The strapping device according to the invention comprises several of the same parts as the devices of the prior art for tightening and securing a strap or belt to a load to be transported or to be held securely together or to a base.

The invention shown in the drawings comprises two mutually pivotable frame parts 1, 2, which are articulated at an axis generally designated by reference numeral 3. One frame part 1 is provided with a handle 4 for tightening operations, the other frame part 2 is provided with a bolt 5 or a rod member for fixing the end of a strap (not shown).

Shaft 3 extends between and through opposing, parallel flanges 7 and 8 of frame sections 1 and 2, respectively. Similar to the prior art, the device according to the present invention is provided with a pawl and ratchet mechanism for providing unidirectional rotation of shaft 3 when sections 1 and 2 are pivoted in opposite directions. The key features of this mechanism are a pair of ratchets 9 fixed to shaft 3 between flanges 7 and 8 but rotatably positioned relative to sections 1 and 2, and two spring-biased pawls 10 and 11 disposed in the respective frame sections 1 and 2. The sliding pawls 10 and 11 can be released from engagement with the ratchet wheels 9 by manually pulling back the pawls 10 and 11 against the action of springs (not shown).

FIG2 shows an embodiment of a shaft 3 according to the present invention. The shaft is provided with two grooves 20, 21 arranged at different angles relative to the axis of rotation, indicated by the dashed line 22. In this embodiment, the grooves 20, 21 are spaced apart so that their upper portions, indicated by reference numeral 23, intersect, making insertion of the strap relatively easy. In this embodiment, the grooves 20, 21 are formed by cutouts in the shaft 3. The ends of the shaft are identical to those of prior art devices and are therefore capable of accommodating the frame and flanges 7, 8, as well as a pair of ratchets 9.

Turning to Figure 3, the brace 30 has been folded into the grooves 20, 21 so that by rotating the shaft 3, the upper portion of the shafts 21', 20' will hold the brace 30 in place in the shaft so that the brace will be wrapped around the shaft 3 by rotation.

FIG4 illustrates another embodiment of the present invention. Shaft 3 is provided with an enlarged cutout portion 25. Enlarged cutout portion 25 spans the diameter of the shaft, i.e., a slot is formed through shaft 3. The extension of enlarged cutout portion 25 in the longitudinal direction of shaft 3 (along axis of rotation 22) intersects at least two grooves. Due to the nature of the design, when the grooves are cut/formed, the center section is severed, resulting in a groove with only one side. The upper portions 20′, 21′ of the grooves will still retain the strap, as described above with reference to FIG3 .

A preferred embodiment of the present invention is shown in Figures 5 and 6. The mechanism that drives and causes the shaft 3 to rotate is the same as that used in all the above-described embodiments. In this embodiment, the shaft 3 is provided with an elongated groove 20 that spans almost the entire distance between the parallel flanges 8. A notch 26 is provided near one of the flanges 8 and is an integral part of the groove 20. Referring to Figure 6, the notch allows a brace 30 to be inserted through its side edge into the notch 26 and slide into the groove 20, so that when the shaft 3 rotates, the upper portion 20' of the shaft will retain the brace 30, causing the brace 30 to be wrapped around the shaft 3.

In Figures 7A and 7B a further embodiment is shown in which a guide element is provided on or as part of the shaft, the guide element being adapted to guide the insertion of the brace through the groove.A further guide element may be provided at a distance from the first guide element.

Claims (9)

1. A load-bearing device comprising at least two frame portions connected by a pivotable connection, one frame portion being attached to a strap, wherein the connection between the pivotable portions is provided with a shaft extending between parallel flanges of the frame portions, the pivotable connection between the pivotable portions being provided with a pawl and ratchet mechanism at opposite ends of the shaft, the pawl and ratchet mechanism providing unidirectional rotation of the shaft when the pivotable basic portions are repeatedly pivoted in opposite directions, the load-bearing device characterized in that the shaft is provided with at least one groove cutting into the body of the shaft, wherein the groove extends into the shaft by less than half the diameter of the shaft, wherein the at least one groove is adapted to receive the strap. 2. The load-bearing device according to claim 1, wherein the extension of the groove in the direction of the axis of rotation of the shaft exceeds 50% of the distance between the parallel flanges. 3. The load binding device according to claim 1, wherein the two grooves are arranged at correspondingly different tilt angles relative to the axis of rotation of the shaft, and the grooves are spaced apart from each other and are oriented in opposite directions. 4. The load binding device according to claim 1, wherein the groove is a cut symmetrically arranged around the center of the shaft at a predetermined distance, wherein the opening of the groove is closer to the center than the bottom of the groove. 5. The load-bearing device according to claim 3 or 4, wherein the groove is connected to the enlarged slit, the enlarged slit spanning the diameter of the shaft and having an extension along the axis of rotation in the longitudinal direction of the shaft, the extension intersecting at least two grooves. 6. The load-bearing device according to claim 1, wherein the guide element is disposed on or as part of the shaft, the guide element being adapted to guide the strapping insertion through the groove. 7. The load-bearing device according to claim 2, wherein the extension of the groove in the direction of the axis of rotation of the shaft exceeds 75% of the distance between the parallel flanges. 8. The load-bearing device according to claim 2, wherein the extension of the groove in the direction of the axis of rotation of the shaft exceeds 90% of the distance between the parallel flanges. 9. A method of using a load-bearing device according to any one of claims 1 to 8, wherein the load-bearing device is selected having a shaft with a width at least corresponding to the strap to be bound, and wherein the strap is laid flat on the shaft, thereafter one or both side edges of the strap are inserted into corresponding grooves provided in the shaft, thereafter a ratchet mechanism is driven to wind the strap onto the shaft, thereby tightening the strap.