NO334817B1 - Device for protection against unwanted release of safety hooks - Google Patents

Abstract

According to the invention, there is provided a securing device adapted to prevent unintentional release of cargo from on-load safety hooks, the securing device comprising at least: a) A first manually releasable securing element adapted to engage a hook housing via at least one engaging means. b) At least one securing means which ensures that the securing element is kept in a fixed position relative to a release mechanism and in engagement with the release mechanism arranged in the hook housing. According to the present invention, a safety assembly is also provided to prevent accidental release of cargo from on-load safety hooks.

Description

The area of technology

[0001] The present invention relates to a device for securing against unwanted

release of safety hooks, as well as a system for the same. Background technology

[0002] In a number of applications, hooks are used that carry a load, and such hooks are generally divided into hooks that can be released from the load they carry when the force applied from the load is relieved from the hook, and hooks that can also be released from the load while the load still applying a force to the hook.

[0003] An example of an area of use for hooks is the offshore and shipping industry.

[0004] For a lifeboat that is placed on the water, there can be fatal consequences if the suspension hook that keeps the lifeboat suspended is released too early while the boat is still hanging above the water. It therefore seems appropriate to have a release system that does not allow the hook to be opened if the boat is not already floating on the water, so that the hook is mainly unloaded. Hooks that work in this way are therefore called "OFF-LOAD" hooks.

[0005] Nevertheless, in cases of disaster it has happened that lifeboats that are safely lowered to the surface of the water still exert a tensile load on the hook, for OFF-LOAD hooks the result can be catastrophic as the lifeboat cannot be detached from a sinking vessel and the vessel will therefore also lower the lifeboat. For this reason, hooks have been developed that can also release loads under load, hooks with such release mechanisms are called "on-load" hooks.

[0006] An example of an "on-load" hook is described in EP 1512621 B. An example of an "OFF-LOAD7"on-load" hook is shown and discussed in a product brochure from the Survival Craft Inspectorate, entitled "Lifeboat and Lifesaving Equipment, Manufacture, Inspection and Maintenance.

[0007] In recent years there have been a number of accidents during training and work with lifeboats due to the on-load suspension hooks having released too early. New regulations to prevent accidental release have been drawn up. This is to ensure that the on-load hooks are constructed in such a way that these, as far as possible, ensure that no unforeseen situations arise during, loading, recording or working with lifeboats on board ships. However, there are a total of at least 30,000 lifeboat hooks of various makes that do not satisfy the new regulations.

[0008] It is therefore a desire to provide a device to ensure the undesired

triggering load from ON_LOAD hooks.

[0009] It is also a purpose according to the present invention to design said device so that an unstable on-load hook can be made "harmless" with simple grips. This means that the hooks should not be able to release unintentionally due to incorrect use, and/or due to lack of/incorrect maintenance.

[0010] A further purpose according to the present invention is to ensure that the lock can in no way be installed incorrectly or operated incorrectly. The lock must be able to withstand release forces as a result of attempts to "release" and at the same time it must be able to withstand a hook that comes out of tolerance.

[0011] Furthermore, the solution must not involve intervention in the hook's construction which could affect the structure and thus go beyond the hook's total strength. This would possibly mean requirements for new tests of each individual hook, which would be impossible in practice.

Summary of the invention

[0012] It is an aim of the present invention to provide a securing device for on-load hook devices as well as a safety assembly comprising parts adapted to engage with the securing device.

[0013] According to the present invention, a safety device adapted to prevent the unintentional release of loads from on-load safety hooks is provided, where the safety device comprises at least: • A first manually releasable safety element adapted to engage with a hook housing via at least one engagement means . • At least one securing means which ensures that the securing element is held in a fixed position relative to a release mechanism and in engagement with the release mechanism arranged in the hook housing.

[0014] According to one aspect of the invention, the first securing element is designed as a sleeve with internal side walls adapted to the external surface at one end of the release mechanism which protrudes from the cork housing.

[0015] According to a second aspect of the invention, the first

the securing element an external perimeter which is arrow-shaped.

[0016] According to yet another aspect of the invention in any combination of the aspects above, the securing element is characterized in that it is adapted to engage with a hook housing via at least one engaging means and the securing element is designed with at least one means to receive said engaging means.

[0017] According to yet another aspect of the invention in any combination of the aspects above, the security element is characterized by

the securing element comprises a means for receiving an intervention means.

[0018] According to yet another aspect of the invention in any combination of the aspects above, the securing element is characterized by the securing element comprising a means for receiving an engaging means, where the engaging means is a stick designed with an eye at one end, where the eye is adapted for fixing of a wire end and where the pin mounted in the middle protrudes so that the pin is adapted to engage with a complementary hole in the hook housing.

[0019] According to yet another aspect of the invention in any combination of the aspects above, the security element is characterized by the fact that the security element comprises means for receiving at least one security means.

[0020] According to yet another aspect of the invention in any combination of the aspects above, the securing device is characterized by the securing element comprising means for receiving a securing means, where the securing means is a securing splint adapted to engage with the securing element via adapted holes in the securing element.

[0021] According to yet another aspect of the invention, the safety pin is characterized by the fact that the safety pin is designed with an arc-shaped part, this arc-shaped part is adapted to a complementary arc-shaped part in the first securing element so that when the safety pin is correctly locked, the aforementioned arc-shaped parts will come into engagement and prevent unwanted movement of the safety pin.

[0022] According to the present invention, a safety assembly is also provided to prevent accidental release of cargo from on-load safety hooks, where the safety assembly comprises at least:

• A first securing element adapted to engage with a hook housing via at least one engaging means and adapted to engage with a first end of a release mechanism. • At least one securing means which ensures that the securing element is held in a fixed position relative to the release mechanism, where the release mechanism is adapted to release a hook body and the release mechanism is rotatably arranged in the hook housing. • A release arm adapted for mounting to a second end of the release mechanism. • A nut which ensures that the release arm is secured to the release mechanism.

[0023] According to one aspect of the invention, the securing element comprises a means for receiving an engaging means, where the engaging means is a pin where the pin mounted in the means protrudes so that the pin is adapted to engage with a complementary hole in the hook housing.

[0024] According to a second aspect of the invention, the at least one securing means is a single securing pin designed to fit into a receiving hole in the safety element when the safety element is engaged with the release mechanism, the securing pin is further adapted to engage with a recess in the release mechanism , so that the safety element is locked to the release mechanism in the axial direction.

Brief description of the figures

[0025] To make it easier to understand the invention, the description will follow

refer to the attached drawings, where

[0026] Figure 1a shows a known on-load hook/release mechanism in a suspended

state,

[0027] Figure 1b illustrates the hook according to Figure 1a during the release process,

[0028] Figure 2 shows an on-load hook assembly where a release shaft and

its locking nut is shown separated from the hook housing

[0029] Figure 3 shows an example of a safety device according to the invention and a safety assembly to prevent accidental release of cargo from on-load safety hooks according to one aspect of the invention,

[0030] Figure 4 shows an example of a security element according to it

present invention,

[0031] Figure 5 shows an example of the safety element in Figure 4 according to the present invention where an intervention means is mounted to the safety element,

[0032] Figure 6 shows an example of an intervention means adapted to intervention in a

hook house,

[0033] Figure 7 shows an example of a securing pin adapted to engage with a

security element according to an aspect of the present invention,

[0034] Figure 8 shows an example of a security device according to it

present invention,

[0035] Figure 9 shows an example of a release shaft according to it

present invention,

[0036] Figure 10 shows an example of a trigger arm according to the present invention

invention,

[0037] Figure 11 shows an example of an arrow element according to an aspect thereof

present invention,

[0038] Figure 12 shows a nut suitable for fixing and securing

the release shaft shown in figure 9,

[0039] Figure 13 shows a hook housing, with a safety assembly according to a

aspect of the present invention,

[0040] Figure 14a shows an example of a hook assembly according to an aspect of the present invention, where the safety element is not engaged with the release shaft, and

[0041] Figure 14b shows an example of a hook assembly according to an aspect of the present invention, where the safety element is in

engagement with the release shaft.

Embodiments of the invention

[0042] In the following, the present invention will be explained by describing preferred embodiments, and by referring to the attached drawings. The person skilled in the art will, however, see other applications and modifications within the scope of the invention as defined in the appended independent claims.

[0043] The terms camshaft, release shaft and release mechanism are

used interchangeably throughout the description.

[0044] Figure 1a shows a schematic diagram of an on-load hook assembly. The figure shows that a load E acts with a force s on a hook H. Since the force S does not act through the rotation point of the hook body H, the force will cause a rotation of the hook body H about the rotation point Q. The rotation is prevented by the hook body H resting against a locking device X. X will thus prevent or allow release of the hook under load, in that X can be rotated about point Z. Figure 1b shows the hook body in a released position.

[0045] In practical embodiments, the locking device X can for example be a camshaft where the hook body H will rest against the cam in a locked position, while the hook body will be able to rotate freely if the camshaft is rotated so that the tail of the hook body is no longer in engagement with the camshaft.

[0046] As indicated, involuntary rotation of the camshaft/release shaft has resulted in incorrect release of load. There is therefore a need to prevent such triggering, alternatively to secure against triggering by other triggering principles.

[0047] According to the present invention, a device 1 is provided which ensures incorrect release by securing a camshaft which normally locks the hook body against rotation.

[0048] The device 1, which ensures against incorrect release of the load when the camshaft, or another type of release shaft, rotates is designed so that the device is rotationally locked to the hook housing, furthermore, the device is designed so that when it is mounted to the camshaft/release shaft, it can the device and the shaft do not rotate independently of each other. This means that the device is rotationally locked to the camshaft/release shaft. The rotational lock between the shaft and the locking device can be implemented in a number of ways known to the person skilled in the art, nut with cotter pin, nut with set screw, splines, press fit and conical adaptation, or as the embodiment in Figure 3 shows in that the cut for the device 1 and the shaft does not are round. The above-mentioned solutions to prevent rotation may be fraught with disadvantages in relation to the release of the securing device 1.

[0049] As mentioned, the securing device is prevented from rotating in relation to the hook housing by the fact that the device in the locked state engages with the hook housing. The securing device is provided with at least one protruding pin, where the pin is adapted to engage with a corresponding number of holes/openings in the hook housing, the engagement preventing rotation of the assembly shaft/securing device.

[0050] In order to be able to release the load in an intentional manner, the securing device must be able to be released from the camshaft/release shaft. The securing device is thus provided with holes adapted to receive one or more locking cotter pins, where the locking cotter pins are adapted to slots in the camshaft/release shaft. By removing at least one locking pin, the securing device can be pulled off the camshaft/release shaft and the shaft can be rotated so that the hook body can be rotated to release the load.

[0051] The expert in the field will be familiar with a number of solutions to ensure axial movement of the securing device. In this context, it is essential that the system is safe, intuitive and that an operator can easily remove at least one locking pin.

[0052] The securing device together with at least one locking pin must be adapted to secure rotation against the camshaft/release shaft and hook housing. The safety device can thus be seen as part of a system where certain prerequisites must be in place for the desired functionality to be achieved.

[0053] The system includes the shaft, which must be adapted to engagement with the securing device and the at least one pin, as well as the hook housing, which must be provided with one or more means that ensure engagement with the securing device.

[0054] The system must also be designed so that the shaft can be rotated, i.e. it must be rotatably arranged through the hook housing, and it must also be provided with a release agent to provide rotation, this agent can be provided in the form of an arm which is fixed on one end of the release shaft accessible to an operator.

A first embodiment of a safety device according to the invention

[0055] A first embodiment of the safety device according to the present invention will now be described with the help of the figures. The securing device is shown in Figure 3 together with other parts which together constitute a system for releasing and securing against unwanted release of cargo. The safety device itself is made up of a few components as shown in figure 3 in the bottom left corner. According to this embodiment, the safety device comprises four constructive parts. These appear clearly in figure 8. The arrow-shaped device 1 adapted to engagement with a release shaft/camshaft is referred to below as the first securing element 1.1 in addition to the first securing element, the securing device according to the first embodiment includes a splinter 82, 72 or a securing splinter 82, 72. Furthermore, a thin wire 83 is seen which is attached to the pin 82, 72 and a protruding pin 62. The purpose of the thin wire is to ensure that the pin 82, 72 is not lost. A band 85 is arranged at the upper end of the pin 82, 72 for easy release of the pin 82, 72. Figure 4 shows the first securing element in more detail. It appears that the first securing element is provided with an opening 45 to receive a pin 62. It is this projecting pin which is adapted to engage a hole in the hook housing so that the release shaft/camshaft cannot be rotated. It can also be seen that the first securing element is designed as a fixed arrow, the shape is functional in the sense that it clearly shows an operator what position the release shaft/camshaft is in. If the arrow points up, it will, according to one embodiment, indicate that the hook has been released for ejaculation. It can also be seen that the first securing element 1 is provided with an opening which is not a regular circle, the opening being complementary to and congruent with one end of the cam shaft/release shaft. The camshaft adapted to this embodiment is shown in Figure 9. It is also seen in Figure 4 an element 1b which has the same shape as the first securing element 1, the element 1b is a "shell" adapted to enclose the first securing element 1. The shell or element 1b can protect the first fuse element 1,

but primarily it is made in a visible color so that

the safety device is clearly visible. The openings, the holes 46 are

adapted to the thickness of the safety pin 72, 82 so that it can be inserted into the hole 46. The safety pin 72, 82, which is shown in more detail in Figure 7. It can be seen from the design that the safety pin is designed with an arc-shaped part, this arc-shaped part is adapted to a complementary arc-shaped part of the first safety element 1 and the shell 1 b When the safety pin is correctly locked, the aforementioned arc-shaped parts will engage and prevent unwanted movement of the safety pin.

[0056] An example of the protruding pin 62 can be seen in Figure 6. In other embodiments, one can imagine that several pins can be used or that one or more pins have a different shape, the important thing here is that a good rotation protection is achieved in relation to to the hook housing where the protruding pin or the protruding pins are to engage.

[0057] As indicated above, other embodiments of the securing device will be able to engage with the camshaft/release shaft in a different way, such as with splines, and the like, the principle is maintained as long as the securing anode/the first securing element is ensured a simultaneous synchronous rotation when they are engaged . Furthermore, the securing pin can be replaced by other types of pins which, for example, pass through the securing element and an outer end of the camshaft/release shaft.

A first embodiment of a system adapted to the rotation protection of the release shaft/camshaft according to the invention

[0058] A first embodiment of a system adapted to the rotation protection of the release shaft/camshaft according to the present invention will now be described with support in the figures. The system is shown in Figure 3, which shows an example of parts that can be replaced with an on-load hook so that the hook can be secured with a securing device according to the invention. It can be seen that the system comprises a release shaft/camshaft, an arrow-shaped disc 6, a release arm 5, a nut 4 and a set screw 9 for the nut 4. The individual elements of the system will now be described separately.

[0059] The camshaft 3 is shown in more detail in Figure 9. It can be seen that the camshaft is provided with a cam part 92 which is adapted to engage with the tail of a hook body. Furthermore, a recess 93 adapted to engagement with the securing pin 72, 82 is seen. A flange is also seen which is indicated adjacent to the cut A-A, the flange forms a contact surface against the hook housing. It can also be seen from Figure 9 that the camshaft 3 is provided with external threads at the outer end opposite the end adapted to engagement with the securing device. Adjacent to the threaded portion is an area adapted to engage with a release arm 5. The cross-section for this portion is given at the section E-E in Figure 9. The section A-A in Figure 9 is adapted to the shape of an opening in an arrow element 6 shown in more detail in Figure 11. The arrow element 6 serves first and above all as a marker that shows the position of the camshaft 3 at all times. Thus the element has a very important function, as an operator will easily see at a quick glance what position the release shaft/camshaft is in. The system is also equipped with lubrication nipples as indicated in figure 3 as element 2 or 8.

[0060] The release arm 5 is shown in figure 10, it can be seen that the internal shape for the shaft opening therein is adapted to the section given at E-E in figure 9. The release arm is threaded onto the camshaft 3's one end which projects outside the hook housing, the arm is secured by the nut 4 which screw on the threaded part of the camshaft. The nut 4 is in turn secured by a set screw 9.

[0061] Figure 13 shows a complete hook assembly with a system for unintentional release of load on on-load hooks according to the present invention, without an attached securing device.

[0062] Figure 14a shows the hook assembly in Figure 13 in fully assembled form without the securing device mounted. Figure 14b shows a complete hook assembly with the securing device fitted.

Definitions and reference numbers

Claims (13)

1. Safety device adapted to prevent the unintentional release of loads from on-load safety hooks, where the safety device comprises at least: a) a first manually releasable safety element (1) adapted to engage with a hook housing via at least one engagement means (52, 62), characterized in that the securing device further comprises: b) at least one securing means (72, 82) which ensures that the securing element (1) is held in a fixed position relative to a release mechanism (3) and in engagement with the release mechanism arranged in the hook housing. 2. Safety device according to patent claim 1, characterized in that the first securing element (1) is designed as a sleeve with internal side walls adapted to the external surface at one end of the release mechanism (3) which protrudes from the cork housing. 3. Safety device according to patent claim 1 or 2, characterized in that the first security element (1) has an external perimeter which is arrow-shaped. 4. Security device according to any of the preceding patent claims, characterized in that the security element (1) is adapted to engage with a hook housing via at least one engagement means (52, 62) and the security element (1) is designed with at least one means (45) for to receive the intervention (52, 62). 5. Safety device according to patent claim 4, characterized in that the securing element comprises a means (45) for receiving an intervention means (52, 62). 6. Safety device according to patent claim 4 or 5, characterized in that the securing element comprises a means (45) for receiving an engagement means (52, 62), where the engagement means (52, 62) is a stick designed with an eye at one end, where the eye is adapted to the attachment of a wire end and where the stick (52, 62) mounted in the means (45) protrude so that the pin is adapted to engage with a complementary hole in the hook housing. 7. Security device according to any of the preceding patent claims, characterized in that the security element (1) comprises means for receiving at least one security means (72, 82). 8. Security device according to any of the preceding patent claims, characterized in that the security element (1) comprises means for receiving a security means (72, 82), where the security means (72, 82) is a security splint (72, 82) adapted to engagement with the securing element (1) via adapted holes (46) in the securing element. 9. Safety device according to patent claim 8, characterized in that the securing pin (72, 82) is designed with an arc-shaped part, this arc-shaped part is adapted to a complementary arc-shaped part in the first securing element (1) so that when the securing pin is correctly locked, the said arc-shaped parts will engage and prevent unwanted movement of the securing pin (72, 82). 10. A safety assembly to prevent accidental release of cargo from on-load safety hooks, where the safety assembly comprises at least: a) a first safety element (1) adapted to engage with a hook housing via at least one means of intervention (52, 62) characterized in that the first securing element (1) is further adapted engagement with a first end of a release mechanism (3), b) at least one securing means (72, 82) which ensures that the securing element (1) is held in a fixed position relative to the release mechanism (3), where the release mechanism (3) is adapted release of a hook body (H) and the release mechanism (3) is rotatably arranged in the hook housing, c) a release arm (5) adapted to be mounted to a second end of the release mechanism (3) d) a nut (4) which ensures that the release arm (5) secured against the release mechanism (3). 11. A safety assembly according to patent claim 10, characterized in that the first safety element (1) is designed as a sleeve with internal side walls adapted to the external surface at the first end of the release mechanism (3) which protrudes from the cork housing. 12. A security assembly according to patent claim 10 or 11, characterized in that the securing element (1) comprises a means (45) for receiving an engaging means (52, 62), where the engaging means (52, 62) is a pin where the pin (52, 62) mounted in the means (45) protrudes so that the pin is adapted to engage with a complementary hole in the hook housing. 13. A safety assembly according to patent claims 10-12, characterized in that the at least one securing means (72, 82) is a single securing pin designed to fit into a receiver hole (46) in the safety element (1) when the safety element (1) is in engagement with the release mechanism (3), the securing pin (72, 82) is further adapted to engage with a recess (93) in the release mechanism (3), so that the safety element is locked to the release mechanism in the axial direction.