The present invention relates to a device for preventing rotation of a nut on a bolt. The present invention further relates to a shackle provided with such a device for preventing rotation of a nut on a bolt.

Shackles are used in lifting operations and static systems as removable links to connect (steel/ synthetic) wire rope, chain and other fittings. Disadvantage of these shackles is that the nut may run loose from the bolt, resulting in a safety risk of disengagement of the bolt from the shackle. To solve this, it is known to provide the bolt of the shackle with a through hole and add a securing means. The securing means function to prevent disengagement of the nut from the bolt. Known securing means are for example cotter pins, split pins and the likes. It is common in the industry to use an (additional) split pin as securing means to prevent disengagement of the nut from the bolt. Due to the shape of the split pin, the split pin blocks the disengagement direction of the nut and thus prevents the nut from running loose. Disadvantage of the use of a split pin or the like is that even though the safety of the closure of the bow shackle is increased by use of the split pin, an additional safety risk is present, namely the risk of elements snagging on the protruding parts of the split pin. A further disadvantage is that the nut may still rotate with respect to its position on the bolt. Another disadvantage of the use of a split pin is that tools are required to install the split pin properly.

It is an object of the invention to provide an improved alternative for securing a nut on a bolt, taking away at least one of the above mentioned disadvantages.

The invention thereto provides a device for preventing rotation of a nut on a bolt, for example in a shackle bolt, comprising a shell part, comprising a receiving space for receiving at least part of the nut; and a securing pin, which extends at least partially between a first and an opposite second side of the shell part and is arranged for cooperating with a pin through hole of the shackle bolt; and wherein the shell part is arranged to at least partially enclose the nut, and wherein preferably the outer surface of the shell part is substantially smooth (in a coupled state). The advantage of this device is that the shell parts receive and secure the nut in its position with respect to the threaded position on the bolt and thus preventing the nut from rotation. The nut is secured by the securing pin from the device according to the present invention, in a similar fashion as the split pin as used in the prior art does. This makes the device easy and intuitive to handle. In an embodiment of the device the shell parts of the device shield the nut and are designed such that it is prevented that objects like lines or ropes snag behind the device, as regularly happens with the use of split pins. It is advantageous when the risk of stuff snagging is reduced, because it increases the safety at the workplace.

The receiving space may also function as an additional securing means, when the receiving space ensures a form-locking of the nut within the receiving space of the device. The receiving space of the device may further protect the nut from outside effects, and may reduce corrosion and filth weakening the connection.

Substantially smooth may for instance mean that there are no protruding parts from the surface. Recesses may be present in the outer surface. Smooth may further mean that any transitions between shapes, recesses, small bumps or the like are smoothened, such that ropes, cords, cables, tools, clothing, will be guided over the surface by the smooth transition, to prevent that objects get snagged behind/onto the device. The surface itself may comprise a texture for a good grip handling of the device, which is still considered to be substantially smooth according to the present invention. It is also possible that the securing pin is a bolt and that the head end of the bolt is visible from a side view. This configuration is also considered to be substantially smooth. To increase the ease of inserting the securing pin in the through hole in the bolt of a shackle it is possible that the securing pin is tapered.

In an embodiment of the device according to the present invention, the shell part comprises a first shell part, said shell part comprising a receiving space for receiving at least a part of the nut; and further comprising a second shell part, said shell part comprising a complementary receiving space for receiving at least another part of the nut. The first and second shell part are connectable. Preferably, the shell parts may be connectable by a securing pin, or for example by a click connection between shell parts. In said embodiment, the securing pin, extends at least between the first and the second shell part and is arranged for cooperating with a pin through hole of the shackle bolt. In a possible variant preferably each of, the first and second shell part comprise integrated means for a complementary connection for connecting both parts to each other, preferably a complementary click connection.

In an embodiment of the device according to the present invention, the first and second shell part each comprise a first edge extending in a first plane and a second edge extending in a second plane, wherein the planes wherein these edges extend are substantially perpendicular, wherein the first edge of the first and second shell part are in contact with each other in a connected state. The contacting edges, at least in the connected state, at least partially enclose the inner space of the shell parts, protecting the inside from incoming dust and the like, as well as protecting the insides from outside elements. In an embodiment of the device, the second edges form a closed circumference in a connected state. Due to the closed circumference, passing objects are less likely to snag on the device or other parts close by. It further protects the device from filth entering and obstructing the operation of the device.

Preferably, the first and the second shell part of the device according to the present invention are substantially identical. This is advantageous to reduce production and inventory cost. It also further increases the ease of use, since any two shell parts according to this embodiment function as a first and second shell part for a device according to the present invention. The user does not have to keep apart first and second parts or distinguish between them, but is able to keep one single supply of shell parts to form the device for securing a nut on a bolt.

The first edge of the first and second shell part may comprise at least one protrusion and at least one complementary recess, wherein the protrusion and recess are positioned such that in a connected state the protrusion of one shell part is received in the recess of the other shell part. In an embodiment one of the shell parts comprises the protrusion and one of the shell parts comprises the complementary recess. It is also possible the each of the shell parts comprises a protrusion and a recess, wherein the protrusion of one part co-acts with the recess of the other part and the other way around. These protrusions and recesses allow to mutually align two shell parts in a correct or predetermined state. In an embodiment the device is made from a polymer or plastic material, which is relatively cheap and easy to process and form, for instance by extrusion. Additionally such device may be relatively lightweight and easy to handle. It is also possible that the device is made from a metal.

The first and second shell part may comprise integrated means for a complementary connection for connecting both parts to each other, preferably a complementary click connection. A click connection is in particular advantageous in an embodiment manufactured from a plastic or polymer material. Preferably each of the first and second shell part have such integrated means. The integrated means allow the two shell parts to be mutually connected around the nut, and could be used to secure or place the device around the nut without the need of additional securing elements. Such click connecting is for instance made using at least one resilient or bendable portion, similarly to the click systems in laminate flooring or zip-tie connections. A further advantage of an embodiment comprising a click connection between shell parts is that no specific tooling is needed to install the device according to the present invention.

In an embodiment the invention provides a device to prevent rotation of a nut on a bolt, for example on a shackle bolt, comprising a first shell part, comprising a receiving space for receiving at least part of the nut; and a second shell part, comprising a complementary receiving space for receiving at least another part of the nut; and a securing pin, which extends at least between the first and the second shell part and is arranged for cooperating with a pin through hole of the bolt; and wherein the first and second shell part are connectable, and wherein preferably the outer surface of the first and second shell part is substantially smooth.

The securing pin may be connected to, or integrally formed with, at least one shell part, protruding from the inner shell of said shell part. By connection or integrally forming the securing pin with a shell part the securing pin will prevent unwanted rotation or disengagement of the shell part and rotation of the nut secured by the shell part is prevented, as the securing pin (in placed condition) is placed in the hole of the shackle bolt. The securing pin may also comprise at least two protruding pins together forming the securing pin, for instance with one protruding pin on each shell part. The two pins for instance meet in the middle, when the two shell parts are placed around the nut.

In an embodiment the first and second shell part are connectable by the securing pin, which is for instance not integrally formed with the shell parts. The securing pin is for instance an at least partly threaded pin secured by a complementary nut. The securing pin for instance extends through a first shell part, into the shackle bolt, into the second shell part and ending up in the complementary nut, securing the elements in place. Preferably neither the pin, nor the complementary nut protrude from the shell parts. For this embodiment the shell parts are preferably manufactured from a metal.

The first and the second shell part may for instance comprise a through hole for receiving at least part of the securing pin. The through hole may for instance be surrounded by a sunken recess, recessed from the outer surface of the shell part for receiving a complementary nut and prevent the complementary nut from protruding from the shell part.

In an embodiment the shell parts and/or the securing pin may be made from metal. Compared to plastic or polymer, a metal material provides additional strength and robustness to the system.

It is advantageous when the first and the second shell part comprise an additional through hole for receiving securing means, for example a steel wire rope or natural/synthetic fibre rope, for securing the shell parts to an external member or to the shackle, to prevent the shell parts from falling down when released. Each shell part of the device further may comprise an additional through hole as a tool for receiving securing means, to secure the shell parts together, which reduces the risk of loosening a shell part while working at a working site. This is advantageous because a loose shell part may fall down when working at height, or a fallen shell part on a floor may cause someone to trip over and get injured. The additional through hole in the device is preferably positioned within outer contour of the device, but may also be positioned as a protruding element, as an eye for receiving securing means.

In an alternative embodiment, the shell part comprises a substantially hexagonal shell portion, wherein the hexagonal shell portion is arranged to enclose the nut and wherein preferably the shell portion extends beyond the nut in the direction of the bolt, in particular in the axial direction of the bolt. Preferably, the hexagonal shell portion comprises an opening, arranged to be aligned with the pin through hole of the bolt in placed condition. Preferably, the hexagonal shell portion comprises a second opening, opposite the first opening, also arranged to be aligned with the pin through hole of the bolt in placed condition. It is possible that one of the first and/or second openings comprises a threaded inner surface for a connection with an at least partly threaded pin. This embodiment is in particular advantageous in combination with a hexagonally shaped nut on a shackle. The complementary shape in combination with a pin, will limit the freedom of rotation and movement of the nut and thus preventing its rotation with respect to the threaded position on the shackle bolt.

To further increase the user friendliness of the device, it is conceivable that the shell parts are provided with visual aiding means to help the user position the shell parts quickly in the right position. An example of visual aiding means helplines which are lines applied on the outer surface of the shell parts, which are positioned such that they correspond to the edges of the nut. For example a hexagonal nut. The visual aiding means may also be a positioning aiding means for positioning of the securing pin. The positioning aiding means may be a circular or dot-shape visual means such as a hollowed out circle or a sticker, which is positioned in line with the securing pin. If the shell parts are made of a plastic or polymer material it is advantageous to integrally form the visual aiding means within the shell parts, for example as a hollowed out line or circle. This is advantageous because it is a low- cost solution and does not take additional time in the production process, while adding value to the device.

The invention also relates to a shell part for use in a device according to the present invention. The invention further relates to a shackle provided with a device according to the invention. Where in this document a nut is mentioned, the nut may comprise any standard or specialized nut in the industry. The nut may have any polygonal shape, such as a hexagon or a square.

The invention further relates to a shackle, provided with a device according to the present invention.

The invention will further be elucidated according to the following figures, wherein Fig. 1 shows a perspective view of a first embodiment in a coupled state according to the present invention;

Fig. 2 shows an exploded view of a first embodiment according to the present invention;

Fig. 3 shows a perspective view of a second embodiment in a coupled state according to the present invention; and

Fig. 4 shows an exploded view of a second embodiment according to the present invention; and

Fig. 5 shows a perspective view of a third embodiment in a coupled state according to the present invention; and

Fig. 6 shows an exploded view of a third embodiment according to the present invention.

Figure 1 shows a device 1 for preventing rotation of a nut on a bolt, in this example in a shackle 2. The figure shows the device 1 in a coupled state wherein a nut is secured on the bolt 12 of the shackle 2. The coupling is made by coupling the first shell part 3 and the second shell part 4. The outer surface of the device 1 is a substantially closed surface in a coupled state. The nut is substantially covered with the device 1 and secured in its position by the securing pin of the device 1 and thus preventing its rotation on the thread, thus preventing rotation of the nut.

The shown embodiment of the device according to the present invention comprises additional helplines 16, 16’, which are lines applied on the outer surface of the shell parts to increase the user friendliness of the device. The helplines 16, 16’ aid the user to make it visually easy to position the device on the nut, because the helplines are positioned such that they correspond to the edges of the nut. In this example a hexagonal nut. In the shown example the helplines are hollowed out lines. The helplines may also be made visible on the outside of the shell part for example by applying the helplines with a different colour on the outside of the shell part. Furthermore, the shown embodiment is provided with a positioning aiding means 16a for the securing pin 10,10a (shown in figure 2), which increases the user friendliness and ease of positioning the securing pin 10,10a properly even further. The positioning aiding means 16a for the securing pin is in this embodiment a hollowed out circle which is positioned in line with the securing pin. The positioning aiding means 16a may also be a visual dot on the same position. If the shell parts are made of a plastic or polymer material the helplines 16, 16’ and the positioning aiding means 16a may be integrated within the shell part.

The coupling in this embodiment is made due to a click mechanism between the shell parts 3,4, an example of which is shown in this figure. The click connection is made by the coupling of an integrated protrusion member 5 of the first shell part 3 into a recess 6 in the second shell part. The recess 6 leaves an opening in the outer surface of the shell part 4. The end tip of the protrusion member 5 is designed such that once coupled the protrusion follows the contour of the outer surface of the opposing shell part 4. This way the recess 6 is at least partly filled by the end of the protrusion member 5. As can be seen in figure 2, the shell parts 3,4 are identical and thus each shell part comprises a protrusion member 5 and a recess 6. It is also possible that the shell parts are not identical, wherein the device comprises one click connection, or three (instead of a multitude of two) in a coupled state.

Each shell part 3,4 of the device 1 further comprises an additional through hole as a tool for receiving securing means (not shown). The through hole in this embodiment is preferably positioned within the outer contour of the device 1 .

The device 1 comprises a smooth outer surface 8. Smooth here means that any transitions between shapes, recesses, small bumps or the like are smoothened, such that ropes, cords, cables, tools, clothing, will be guided over the surface by the smooth transition, to prevent that third objects get snagged behind/onto the device. The surface itself has a smooth non-rough finish due to the choice for a polymer material. The device may also be manufactured from metal. The device 1 fully encloses the nut 9, this is done by receiving the nut 9 in the receiving space 15, which consists of a receiving space 15a from the first shell part 3 and complementary receiving space 15b from the second shell part 4. The shape of the receiving space 15, is complementary to the shape of the nut, which means that the inner contour of the receiving space 15 follows the contour of the nut, preferably a hexagonal shape of a square shape, Consequently, the inner contour of the receiving space 15a and 15b forms a part of said contour or shape.

Figure 2 shows the first embodiment of figure 1 in an exploded view. In this view the securing pin 10 is visible. The securing pin 10 is designed for cooperation with the through hole 11 of the shackle bolt 12, to secure the nut 9. The securing pin 10 is an integral part of the shell part 3, 4. Each shell part comprises a securing pin 10, 10a since the parts are identical. The securing pins 10, 10a (dashed lines), each extend within the through hole 11 in the shackle bolt from their respective sides. They may be in abutting contact in a coupled state, or a small distance between them may be present. The securing pins 10, 10a are preferably tapered, or frustoconically shaped at their ends. This is advantageous for the orientation and ease of placing and inserting the pin into the through hole 11 .

In this embodiment, the first shell part 3 can be provided with a guiding protrusion 13a and the second shell part with a complementary recess 14a. The second shell part also comprises a guiding protrusion 14b (not visible) and the first shell part 3 comprises a complementary recess 13b (not visible). These guiding protrusions 13a, 14b and complementary recesses 14a, 13b are positioned at the edges of the shell parts 3, 4.

Figure 3 and 4 show a second embodiment of the device 20 for securing a nut 9 in a bow shackle 2, wherein the shell parts are coupled by the securing pin 30, wherein in this embodiment the securing pin 30 is a bolt. The securing pin 30 keeps the shell parts in position and around the shackle nut 9. The device 20 according to the second embodiment also comprises a first shell part 23 and a second shell part 24. These shell parts 23, 24, together form a receiving space 35 for the nut 9. The first shell part 23 comprises a first receiving space 35a and the second shell part comprises a complementary receiving space (not shown). The two shell parts 23, 24 are coupled by the securing pin 30. The securing pin 30 couples the first shell part 23 with the second shell part 24, while securing the nut 9 by extending through hole 11 in the coupled state. The shell parts 23, 24 keep the nut 9 in position with relation to the thread and preventing rotation of the nut 9. The securing pin 30 comprises a headend 31 , and a threaded opposite end 30a. The threaded opposite end 30a is secured in the threaded securing nut 32. The securing nut 32 is held within the complementary sunken recess 34, which prevents the nut from running loose due to its shape. The securing nut 32 is rotationally locked in by the polygonal shape of the nut 32 and corresponding polygonal shape of the sunken recess 34. The sunken recess 34 is a preferred embodiment, but not necessary.

The shown embodiment of the device according to the present invention comprises additional helplines 36, 36’, which are lines applied on the outer surface of the shell parts to increase the user friendliness of the device. The helplines 36, 36’ aid the user to make it visually easy to position the device on the nut, because the helplines are positioned such that they correspond to the edges of the nut. In this example a hexagonal nut. In the shown example the helplines are hollowed out lines. The helplines may also be made visible on the outside of the shell part for example by applying the helplines with a different colour on the outside of the shell part. If the shell parts are made of a plastic or polymer material the helplines 16, Wand the positioning aiding means 16a may be integrated within the shell part.

Figure 5 and 6 show a third embodiment 40 of a device according to the present invention, preventing the rotation of a nut 9 on a shackle bolt 12. The device 40 comprises a hexagonal shell part 42, comprising a receiving space 45 for receiving at least part of the nut 9. The device 40 further comprises a securing pin 41 , in this embodiment a securing bolt. The securing pin 41 extends at least between a first side and a second side of the shell part and is arranged for cooperating with a pin through hole 11 of the shackle bolt 12. The shell part 42 comprises a first and a second opening 42a, 42b which are located at opposite sides of the shell part. In a coupled state the openings 42a, 42b are aligned with the through hole 11 of the shackle bolt 12. The securing pin 41 extends through each opening 42a, 42b, 11 . The second opening 42b may also be a threaded opening. Due to the complementary shape of the shell part 42 with the shape of the shackle nut 9 and the presence of the securing pin 41 , the rotation of the shackle nut 9 with respect to its threaded position on the shackle bolt 12 is prevented. The shell part 42 of this embodiment fully encloses the hexagonal circumference of the nut 9. Preferably the shell part 42 and the nut 9 are in abutting contact, but there may also be a small space in between them, for example about 1 mm. The outer surface of the shell part 41 is substantially smooth. To improve the device 40 even further the shell part 41 may be provided with a sunken recess similar to the sunken recess shown in the second embodiment. This will further reduce the risk of stuff snagging behind the device. The third embodiment as shown in figure 4 and 5 is preferably made from metal. The shell part 42 is hexagonally shaped, because the nut 9 of the shackle comprises a hexagonal shape. It is also possible that the shell part 42 has another polygonal shape, such as a square, in case the nut 9 comprises a different shape. The shape of the shell part 42 will be complementary with the shape of the nut 9 of the shackle.