Lift block system, lift assembly, vessel or barge and method

Abstract

A lifting block system for selectively lifting a lifting load using fewer or more slings of a lifting rigging wherein an upper block assembly is configured to block upward movement of a suspended second lower block pulley assembly toward the upper block assembly, the suspended first lower block pulley assembly and the connected lower block base are allowed to move upwards towards the upper block assembly, so that the second lower block pulley assembly can be unloaded by pulling the first lower block pulley assembly and the connected lower block base upwards towards the upper block assembly beyond a predetermined limit; wherein the unloaded second lower block pulley assembly can be disconnected from the lower block base, thereby reducing the number of slings that the lower block base hangs from the upper block assembly.

Description

Technical Field

[0001] The present invention relates to a lifting block system for selectively lifting a lifting load using fewer or more slings of a lifting tackle. The present invention further relates to: a lifting assembly including the lifting block system; a ship or barge provided with the lifting assembly; and a method of adjusting the effective number of slings in the lifting assembly. Background Art

[0002] There are known lifting block systems for selectively lifting a lifting load using fewer or more slings of a lifting tackle, particularly in the form of so-called "separable blocks", which means that one or more pulley components of the lifting block system can be separated or "detached" from the lower main component of the lifting block system, such that the corresponding slings can be effectively disabled as required. Then, such separated pulley components can be parked at a high position, for example, parked at the so-called upper block of the system, while the lifting tackle can be retained, i.e., there is no need to thread the tackle. Subsequently, the disabled slings can be re-enabled by reconnecting the separated components to the lower main component. Thus, it is possible to selectively use fewer or more slings of a lifting tackle to lift a load, while the lifting tackle itself can remain unchanged throughout the lifting operation. This selectivity can be beneficial because fewer slings generally allow for higher lifting speeds and greater vertical lifting ranges, while more slings generally allow for greater lifting loads. Therefore, depending on the characteristics of a specific lifting operation, the lifting personnel can decide to use fewer or more slings without changing the threading of the lifting tackle. This practice is known in offshore lifting operations, where the lifting block system can be suspended from a lifting boom (such as the lifting boom of a crane mounted on a ship) by a lifting tackle.

[0003] Known lifting block systems can be separated and reconnected when supported on a dedicated platform or bracket (sometimes referred to as a "basketing"), for example, on the deck of a ship, such that the weight of the lifting block system can be unloaded from the lifting tackle and the lifting block system can be stabilized, and the staff can perform the necessary mechanical adjustments.

[0004] There is a current need to make offshore lifting operations more efficient and flexible, particularly while maintaining or improving reliability, durability, and safety. In particular, there is a need to achieve higher lifting levels without correspondingly increasing the size of the ship and while maintaining or improving efficiency, for example, in the scenario of installing and maintaining offshore wind turbines. Summary of the Invention

[0005] The object of the present invention is to address one or more of the above needs. The object is to provide a lifting block system, particularly for offshore lifting operations, in which the effective number of slings can be adjusted more easily, more quickly, and / or under a wider range of conditions. The object is to provide at least alternative lifting block systems and / or lifting assemblies.

[0006] In addition, aspects of the present invention provide a lifting block system for selectively lifting a lifting load using fewer or more slings of a lifting rigging. The lifting block system includes: an upper block assembly including a plurality of interconnected upper block pulleys configured to support the slings; and a lower block subsystem. The lower block subsystem includes: a lower block base configured to suspend the lifting load thereon; and a plurality of lower block pulley assemblies. Each of the lower block pulley assemblies is connectable to the lower block base and each includes a lower block pulley that is suspended from an upper block pulley by some of the slings. The plurality of lower block pulley assemblies includes one or more first lower block pulley assemblies and one or more second lower block pulley assemblies.

[0007] The upper block assembly is configured to block the upward movement of the suspended second lower block assembly toward the upper block assembly while allowing the suspended first lower block assembly together with the connected lower block base to move upward toward the upper block assembly when the first and second lower block assemblies are connected to the lower block base and pulled upward by shortening the slings, so that the second lower block assembly can be unloaded by pulling the first lower block assembly together with the connected lower block base upward toward the upper block assembly beyond a predetermined limit.

[0008] The unloaded second lower block pulley assembly can be disconnected from the lower block base, thereby reducing the number of slings suspending the lower block base from the upper block assembly.

[0009] Advantageously, in order to use fewer or more slings, the lifting block system does not need to be received in a so-called "basketing" on the deck. Instead, in order to use fewer slings, the second lower block pulley assembly can be disconnected while the lifting block system is suspended from a lifting arm (such as a boom or a gin pole in a crane). In order to use more slings, the second lower block pulley assembly can be reconnected, essentially by reversing the steps for disconnection, again without placing the lifting block system or any of its components in a basket or the like. This type of connection and disconnection during suspension is not used in conventional lifting block assemblies, where there is typically no distinction between lower block pulley assemblies as to how far each pulley assembly can be pulled upward toward the upper block assembly. In the lifting block system according to the present invention, this distinction advantageously enables selective unloading of the lower block pulley assemblies, particularly the second lower block pulley assembly, while the first lower block pulley assembly holds the load, thereby also keeping the connected lower block base suspended. In addition, this selective unloading can make the disconnection and subsequent reconnection of the second lower block pulley assembly less laborious, particularly compared to conventional methods where disconnection and reconnection involve hammering while the lifting block system is received in a basket. The disconnection and / or reconnection can even be partially or fully automated, for example using a motor, as further explained elsewhere herein.

[0010] It should be understood that, herein, the expression of unloading the second lower block pulley assembly can be understood as removing an external weight, in particular the weight of the lower block base, from the pulley assembly, so that the second lower block pulley assembly can be disconnected from the lower block base, and the weight of the lower block base does not cause friction or impact during the disconnection process. This unloading is basically achieved by lifting the lower block base relative to the second lower block pulley assembly, which in turn is basically achieved by the difference in how far the first and second lower block pulley assemblies can be pulled upward before being blocked by the upper block assembly.

[0011] It should be understood that this difference in how high the lower block pulley assembly can be lifted can be achieved in various ways. In some embodiments, the upper block engagement surface of the second lower block pulley assembly is at a higher level than such an engagement surface of the first lower block pulley assembly, while the blocking member of the upper block pulley assembly is configured to be at the same level as the engagement surfaces of the lower block pulley assemblies. Alternatively, the engagement surfaces of the lower block pulley assemblies can be at the same level, while the blocking member is configured to engage with engagement surfaces of different types of lower block pulley assemblies at different levels. There may be further variations, such as where both the blocking member and the engagement surface are configured to contribute to the differentiation. In addition, in addition to a single blocking member, different blocking members can be provided for different lower block pulley assemblies, for example, at different levels. Thus, the aforementioned predetermined limit can be achieved in various ways, but can generally be interpreted as a vertical limit relative to the upper block assembly, which can be traversed upward by the first lower block pulley assembly, while a similar upward movement of the second lower block pulley assembly relative to the upper block assembly is blocked by the upper block assembly.

[0012] Thus, by a relatively simple structural differentiation in the lifting block system, the effective number of slings can be adjusted relatively easily and quickly, especially without lowering the lifting block system or its components into a so-called hanging basket.

[0013] Preferably, the upper block assembly is configured to block the suspended first lower block pulley assembly from moving upward toward the upper block assembly beyond an additional predetermined limit that is closer to the upper block assembly than the predetermined limit, the additional predetermined limit being, for example, on the downward-facing side of the upper block assembly. This can advantageously prevent the second lower block pulley assembly from being strained during disconnection, especially without the need to actively position the first lower block pulley assembly with high precision, which is difficult to achieve using only a winch associated with the rigging. The distance between the predetermined limit and the additional predetermined limit is preferably selected according to one or more dimensions in the connection mechanism of the second lower block pulley assembly, especially the available clearance dimension therein, such that the connection between the second lower block pulley assembly and the lower block base can be kept substantially strain-free relatively easily during disconnection and / or reconnection.

[0014] The disconnectability and reconnectability of the second pulley assemblies of the lower block relative to the lower block base can be achieved in a variety of ways.

[0015] Preferably, each of the second lower block pulley assemblies is connectable to the lower block base so as to be rotatable relative to the lower block base about its respective axis of rotation. Preferably, each of the first lower block pulley assemblies is similarly connectable to the lower block base.

[0016] It is known that rotating the lower block pulley assemblies can facilitate the stable suspension of the lower block subsystem, in particular to promote substantially equal rope tensions in different pulleys and to avoid so-called lateral traction, such as uneven winding when multiple winches are used on the same lifting rigging. Such rotation can be applied to the lifting block system of the present disclosure with corresponding advantages, thereby improving the usability and versatility of the lifting block system.

[0017] Preferably, the lifting block system includes a connection mechanism for each of the second lower block pulley assemblies, and preferably also for one or more of the first lower block pulley assemblies, the connection mechanism being configured to provide the connection ability and disconnection ability of each of the lower block pulley assemblies relative to the lower block base.

[0018] Preferably, the connection mechanism is further configured to provide preferred rotatability of each of the lower block pulley assemblies relative to the lower block base about the respective axis of rotation when connected. In this case, the connection mechanism can also be represented as a combined connection and rotation mechanism.

[0019] Thereby, a relatively lightweight and compact lifting block system can be provided, in which the above-described rotation function and connection ability and disconnectability are structurally combined. However, in an embodiment, the rotation function can be omitted, or can be implemented separately from the connection mechanism, for example for one, some or all of the lower block pulley assemblies.

[0020] Preferably, the connection mechanism is included by the lower block base, in particular fixed to the lower block base.

[0021] In this way, the second lower block pulley assemblies can be relatively lightweight, which is particularly advantageous when disconnected from the lower block base and held at a higher level (such as in the upper block assembly). It should be understood that one or more interface-related elements (such as bearings) of such a mechanism can be included by the second upper block pulley assemblies. Alternatively or additionally, such a connection mechanism can be included by the lower block pulley assemblies, in particular fixed to the lower block pulley assemblies, for example for one, some or all of the lower block pulley assemblies.

[0022] Preferably, the connection mechanism includes at least one shaft assembly, the shaft assembly including one or more shaft elements, e.g., aligned with an optional axis of rotation, the shaft assembly being adjustable between a retracted state and an extended state, wherein in the extended state, the shaft element interconnects the corresponding lower block pulley assembly with the lower block base, and wherein in the retracted state, the shaft element releases the corresponding lower block pulley assembly relative to the lower block base.

[0023] Such an adjustable shaft assembly can advantageously provide a combination of the above-described connection, disconnection, and rotation functions, if such a combination is desired. In any case, such an adjustable shaft assembly can form and / or contribute to a relatively compact and efficient connection mechanism.

[0024] Preferably, in the extended state, each shaft element extends through a corresponding shaft opening in the respective lower block pulley assembly and / or through a corresponding shaft opening in the lower block base, and wherein in the retracted state, the shaft element is located outside of at least one of the shaft openings, preferably outside of the shaft openings of the lower block assembly. Herein, the term shaft opening can be interpreted as an opening through which a shaft element of the shaft assembly can extend to form a load-bearing interface therebetween, and the shaft opening is not part of the shaft assembly itself. Thus, for example, if the shaft assembly includes a housing in which the shaft element is movably received, the interior of the housing is not considered a shaft opening herein.

[0025] Thereby, the shaft assembly can provide the above-described connection and disconnection functions. In particular, when the shaft element is located outside of at least one shaft opening, the lower block pulley assembly can thereby be disconnected from the lower block base. In the extended state, the shaft element can extend through the corresponding openings of the lower block pulley assembly and the lower block base, thereby connecting these elements, e.g., rotatably connecting these elements about an optional axis of rotation. Alternatively, the shaft element can extend through a shaft opening in only one of the elements, and the connection to the other element can be provided differently, e.g., in the form of a cantilever connection, such that the shaft element can provide a cantilever support. However, preferably, the shaft element provides a so-called simple support in the extended state, in particular, connecting to one of the elements (e.g., the lower block base) on both sides of the connection to another element (e.g., the lower block pulley assembly).

[0026] Preferably, the dimensions and / or shape of the shaft element and the corresponding shaft opening of the lower block pulley assembly are designed to provide a clearance therebetween when the shaft assembly is in the extended state, while also providing a substantially mating interface therebetween along a partial circumference of the shaft element and the shaft opening to transfer loads therebetween during use.

[0027] In this way, the shaft element can extend through and retract from the shaft opening relatively easily, while still being able to achieve a well-distributed load transfer therebetween when connected.

[0028] Preferably, when the shaft assembly is in the extended state, the section of the shaft element extending into the shaft opening of the lower block pulley assembly and the shaft opening itself have mutually different cross-sectional shapes, in particular only along a limited circumferential part, including the part configured to provide the load-bearing interface F, having mutually corresponding radii.

[0029] In this way, the aforementioned dimensions and / or shapes can be achieved to provide clearance and well-distributed load transfer.

[0030] Preferably, when the shaft assembly is in the extended state, the section of the shaft element extending in the shaft opening of the lower block pulley assembly and / or the shaft opening itself is provided with bearings to reduce the rotational friction between the shaft opening and the shaft element when the shaft assembly is in the extended state, in particular around an optional axis of rotation.

[0031] If required, in this way, smooth and durable rotation can be provided. In any case, wear can be prevented, and a self-stabilizing interface can be provided thereby. Alternatively or additionally, such bearing can be provided on the shaft element itself. In some cases, such bearing can be omitted, for example when rotation is not required. The shaft element and the corresponding shaft opening do not need to be shaped to be able to rotate axially relative to each other around the shaft element, and the axes of the shaft elements of the same shaft assembly do not need to be aligned with each other.

[0032] Preferably, the lifting block system includes at least one motor and / or gearbox, which is coupled to, at least capable of being coupled to, the shaft element for adjusting the shaft assembly between the retracted state and the extended state by the drive of the motor and / or gearbox.

[0033] In the case of a motor, the shaft assembly can be adjusted automatically and / or remotely without personnel adjusting at the shaft assembly, so that the adjustment can be carried out, for example, at a high place instead of, for example, at the deck level. Alternatively, the adjustment can be driven by personnel, for example using a sling or other tools, such as from a platform at the tip of a boom suspended near the lifting block system. A gearbox, for example, between the motor and the shaft assembly or between the tool and the shaft assembly, can provide a suitable and convenient transmission.

[0034] Preferably, a plurality of shaft elements are coupled to the same motor and / or gearbox in at least one motor and / or gearbox, in particular for synchronously adjusting the plurality of shaft elements between the retracted state and the extended state, wherein in particular, the plurality of shaft elements are included by the same shaft assembly and / or are used for connecting to the same lower block pulley assembly and / or aligning with the same axis. For example, the gearbox can have a single input shaft driven by a motor or a tool and a plurality of output shafts coupled to the corresponding shaft elements.

[0035] In this way, the lifting block system can be relatively compact, taking advantage of the concept that the shaft elements of the same lower block pulley assembly generally do not need to operate independently of each other.

[0036] Preferably, the motor and / or gearbox is coupled to the shaft element via a conversion mechanism configured to convert the rotation of the output shaft of the motor into an axial translation of the shaft element.

[0037] Thereby, the shaft element can be adjusted by translation along its axis while the motor can be a rotary motor. A flexible coupling can be provided, for example as part of the conversion mechanism, to allow for tolerating minor misalignments that may occur.

[0038] The first lower block pulley assembly is preferably disconnectable from the lower block base and subsequently re - connectable to the lower block base, for example when the lower block base is placed in a hanging basket or the like for direct access by personnel. Thus, the lower block base can be released from the first lower block pulley assembly if needed, for example during relatively long transportation and / or maintenance periods. Additionally, a connection mechanism can be provided for the first lower block pulley assembly, for example similar to that of the second lower block pulley assembly. However, the disconnection of the first lower block pulley assembly from the lower block base is preferably only performed when the lower block base is stably supported in the hanging basket, otherwise it is preferably actively and / or inherently inhibited to prevent accidental release of the lower block base while suspended.

[0039] Preferably, a guiding structure, particularly a centering structure, is provided in the lifting block system to guide, for example: the relative positioning of the lower block pulley assembly with respect to the blocking member of the upper block assembly; and / or the relative positioning of the second lower block pulley assembly, particularly its shaft opening, with respect to the lower block base and / or the shaft assembly.

[0040] On the other hand, a lifting assembly is provided for selectively lifting a lifting load using fewer or more slings of a lifting tackle, the lifting assembly comprising a lifting block system and a lifting tackle as described herein.

[0041] Such a lifting assembly provides the above - mentioned advantages.

[0042] Preferably, the lifting assembly includes a lifting arm, such as a boom or an A - frame, where the lifting block system is suspended from the lifting arm, and the lifting assembly preferably includes one or more winches engaged with the lifting tackle for adjusting the length of the slings.

[0043] Thus, the lifting assembly and the lifting block system can be used for a variety of lifting operations.

[0044] On the other hand, a ship or barge provided with a lifting assembly as described herein is provided, particularly for offshore lifting operations.

[0045] Such a ship or barge has the above - mentioned advantages.

[0046] On the other hand, a method for adjusting the effective number of slings in a lifting assembly is provided. The method includes providing a lifting assembly including a lifting arm as described herein.

[0047] The method includes: if a second lower block pulley assembly is connected to a lower block base, using a lifting rigging to pull the first lower block pulley assembly together with the connected lower block base upwardly beyond a predetermined limit towards an upper block assembly, thereby unloading the second lower block pulley assembly and disconnecting the unloaded second lower block pulley assembly from the lower pulley base, thereby reducing the effective number of slings.

[0048] Alternatively or additionally, the method includes, if the second lower block pulley assembly is disconnected from the lower block base, connecting the second lower block pulley assembly to the lower block base, particularly when the lower block base is suspended from the upper block assembly by a lifting rigging and the first lower block pulley assembly is positioned beyond a predetermined limit towards the upper block assembly, thereby increasing the effective number of slings. As described elsewhere herein, the connection of the second lower block pulley assembly can be achieved by reversing the steps used for the previous disconnection. In particular, when the first lower block pulley assembly is raised beyond a predetermined limit L, the second lower block pulley assembly can be reconnected again such that the second lower block pulley assembly is not immediately loaded upon connection, but can be loaded subsequently by lowering the lower block subsystem from the upper block assembly.

[0049] This method provides the above advantages.

[0050] As explained elsewhere herein, to avoid tensioning, the first lower block pulley assembly is preferably raised beyond a predetermined limit but not beyond an additional predetermined limit, particularly since the upper block assembly blocks further upward movement of the first lower block pulley assembly beyond the additional predetermined limit.

[0051] On the other hand, the use of the lifting block system, lifting assembly and / or ship or barge described herein for offshore lifting operations, particularly as part of an offshore wind turbine installation operation, is provided.

[0052] Such use provides the above advantages.

[0053] It should be understood that the various aspects and options described herein can be combined in various ways. For example, the options described for the lifting block system, lifting assembly and / or ship or barge can be applied correspondingly to the method and / or use, and vice versa. Detailed Description

[0054] Hereinafter, the present invention will be further explained using examples of embodiments and drawings. The drawings are schematic and only show examples. In the drawings, corresponding elements are provided with corresponding reference numerals. In the drawings:

[0055] Figure 1 A perspective view of the lower block subsystem of the lifting block system is shown, where the first and second lower block pulley assemblies are connected to the lower block base;

[0056] Figure 2 Shows Figure 1 A partially open view of the lower block subsystem;

[0057] Figure 3A And Figure 3B Respectively show a partially open side view and a partially open front view of the lifting block system including a lower block subsystem and an upper block assembly similar to the lower block subsystem of Figure 1 And Figure 2 ;

[0058] Figure 4A And Figure 4B Respectively show a partially open side view and a partially open front view of a lifting block system similar to the lifting block system of Figure 3A - Figure 3B , where the lower block subsystem has been pulled upward such that the second lower block pulley assembly contacts the upper block assembly;

[0059] Figure 5 Shows Figure 4B Detail V;

[0060] Figure 6 Shows the detail corresponding to Figure 5 , where the lower block subsystem has been pulled further upward;

[0061] Figure 7 Shows Figure 4A Detail VII, particularly showing a part of the shaft assembly;

[0062] Figure 8 Shows the detail corresponding to Figure 7 , where the lower block subsystem has been pulled further upward, substantially as shown in Figure 6 ;

[0063] Figure 9 A perspective view of the shaft element of the shaft assembly is shown;

[0064] Figure 10 Shows Figure 9 A cross-sectional axial view of a section of the shaft element in the shaft opening of the corresponding lower block pulley assembly in

[0065] Figure 11 Shows a partially open side view of the shaft assembly corresponding to Figure 8 , where the shaft assembly is in a retracted state;

[0066] Figure 12 Shows a lifting block system corresponding to Figure 11Corresponding views, in which the lower block base and the connected first lower block pulley assembly have been lowered from the upper block assembly, while the second lower block pulley assembly remains in the upper block assembly;

[0067] Figure 13A and Figure 13B respectively show views corresponding to Figure 4A and Figure 4B in which, compared with Figure 12 the lower block base and the connected first lower block pulley assembly have been further lowered;

[0068] Figure 14 shows a partially open perspective view of the details of a shaft assembly similar to the shaft assembly of Figure 11 and Figure 12 ;

[0069] Figure 15 shows a perspective view of a lifting block system similar to other shown examples in a state corresponding to Figure 13A - Figure 13B ; and

[0070] Figure 16 shows a side view of a ship or barge having a lifting assembly including a lifting block system and with a lifting load suspended from the lifting block system.

[0071] The drawings show the lifting block system 1 in various ways, which is used to selectively lift a lifting load 2 using fewer or more slings 3 of a lifting tackle 4. The lifting block system 1 includes: an upper block assembly 5, which includes a plurality of interconnected upper block pulleys 6 configured to support the sling 3; and a lower block subsystem 7.

[0072] The drawings also show a lifting assembly 8 for selectively lifting a lifting load 2 using fewer or more slings 3 of a lifting tackle 4, which includes a lifting block system 1 and a lifting tackle 4.

[0073] For clarity, this lifting tackle 4 is omitted in some of the drawings. However, those skilled in the art benefiting from this disclosure will readily understand how the lifting tackle is arranged in the shown examples, especially when the sling 3 extends substantially vertically between the pulley 6 of the upper block assembly 5 and the pulley 15 of the lower block subsystem 7 (for example, as indicated by the pulleys 6 and 15 in Figure 3A - Figure 3B ).

[0074] Refer to Figure 16, the lifting assembly 8 may further include a lifting arm 9, such as a boom or an A-frame, where the lifting block system 1 may be suspended from the lifting arm 9, and where the lifting assembly 8 preferably includes one or more winches 10 that engage with the lifting blocks 4 for adjusting the length of the sling 3. Here, a crane-type lifting assembly 8 is shown, but it should be understood that any type of lifting assembly suitable for use with a lifting block system may be used. As Figure 16 shown, a ship or barge 11 may be provided with such a lifting assembly 8, particularly for offshore lifting operations.

[0075] The lower block subsystem 7 of the lifting block system 1 includes: a lower block base 12 configured to suspend a lifting load thereon, such as using a lifting hook 13 included in and / or connected to the lower block base 12; and a plurality of lower block pulley assemblies 14, each lower block pulley assembly being connectable to the lower block base 12, and each lower block pulley assembly including a lower block pulley 15, the lower block pulley being suspendable from the upper block pulley 6 by some slings 3. The plurality of lower block pulley assemblies 14 includes one or more first lower block pulley assemblies 14a and one or more second lower block pulley assemblies 14b. Herein, the reference numeral 14 is used generally to refer to one or more lower block pulley assemblies and thus also refers to the first and second lower block pulley assemblies 14a and 14b where applicable.

[0076] The upper block assembly 5 is configured to block the suspended second lower block assembly 14b from moving upward toward the upper block assembly 5 while allowing the suspended first lower block assembly 14a together with the connected lower block base 12 to move upward toward the upper block assembly 5 when the first and second lower block assemblies 14a, 14b are connected to the lower block base 12 and pulled upward by shortening the sling 3, so that the second lower block assembly 14b can be unloaded by pulling the first lower block assembly 14a together with the connected lower block base 12 upward toward the upper block assembly 5 beyond a predetermined limit L.

[0077] In Figure 3A - Figure 3B it can be seen that the lower block subsystem 7 is still located at a certain distance below the upper block assembly 5, and each lower block pulley assembly 14 is still connected to the lower block base 12, thus similar to Figure 1 and Figure 2 , for example, when all available slings 3 ( Figure 3A - Figure 3B not shown in Figure 5 have been used to lift a relatively heavy lifting load. Subsequently, as described below, the effective number of slings can be reduced, for example, for lifting a lighter lifting load faster and / or farther. In Figure 4A - Figure 4B, it can be seen that the first lower pulley assembly 14a, particularly its upper block engaging surface 24a, is pulled upward but has not yet exceeded the predetermined limit L, while the second lower pulley assembly 14b, particularly its upper block engaging surface 24b, has contacted the blocking member 25 of the upper block assembly 5 and is here beyond the predetermined limit L. In Figure 6 , the first lower pulley assembly 14a having the engaging surface 24a is further pulled upward to the predetermined limit L, where it is adjacent to the blocking member 25 and may but does not necessarily contact it. Since the blocking member 25 previously blocked the upward movement of the second lower pulley assembly 14b at its engaging surface 24b, the second lower pulley assembly 14b is actually unloaded at this stage, that is, it no longer supports any weight of the lower pulley base 12.

[0078] The predetermined limit L can be located at a relatively small distance d from the downward side of the blocking member 25, for example, a distance of about 12 mm, which is sufficient to achieve unloading, at least when the structures involved are sufficiently rigid, such that on the one hand, the small distance d is not absorbed by the deformation between the engaging surfaces 24, and on the other hand, it is not absorbed by the connection between the lower pulley assembly and the lower block base 12, here the shaft opening 19, which will be further explained herein.

[0079] As will be further explained herein, the unloaded second lower block pulley assembly 14b can be disconnected from the lower block base 12, thereby reducing the number of slings 3 that suspend the lower block base 12 from the upper block assembly 5, that is, the effective number of slings. In particular, the disconnected second lower block assembly 14b can be retained at the upper block assembly 5 when not in use, as Figure 13A - Figure 13B shown, and due to the weight of the still-suspended lower block base 12 and / or the first lower block pulley assembly 14a and / or the lifting rigging 4, the tension in the lifting rigging 4 basically holds it there. To subsequently increase the effective number of slings again, the process can be basically reversed, that is, when the first lower block pulley assembly 14a is pulled upward beyond the predetermined limit L, the second lower block pulley assembly 14b can be reconnected again such that the second lower block pulley assembly 14b is not immediately loaded when connected, but can be loaded subsequently by lowering the lower block subsystem 7 from the upper block assembly 5.

[0080] Such a lifting block system 1, lifting assembly 8, and / or ship or barge 11 can be used for offshore lifting operations, for example, as part of an offshore wind turbine installation operation.

[0081] This lifting assembly 8 is capable of adjusting the effective number of slings 3 therein. For example, if the second lower block assembly 14b is connected to the lower block base 12 using the lifting tackle 4, the first lower block assembly 14a connected to the lower block base 12 may be pulled upward toward the upper block assembly 5 beyond a predetermined limit L, thereby unloading the second lower block assembly 14b. Then, the unloaded second lower block assembly 14b may be disconnected from the lower block base 12, thereby reducing the effective number of slings 3.

[0082] Alternatively or additionally, if the second lower block assembly 14b is disconnected from the lower block base 12, the second lower block assembly 14b can be connected to the lower block base 12, particularly when the lower block base 12 is suspended from the upper block assembly 5 by the lifting tackle 4 and the first lower block pulley assembly 14a is positioned beyond the predetermined limit L toward the upper block assembly 5, thereby increasing the effective number of slings 3.

[0083] In an embodiment, including in the illustrated example, the second lower block assembly 14b and preferably the first lower block pulley assembly 14a are each connectable to the lower block base 12 so as to be rotatable relative to the lower block base about respective rotational axes S, which extend transversely here to the main direction of the sling 3 and transversely to the rotational axes of the pulleys 6, 15. Alternatively, such rotational axes may extend, for example, parallel to the rotational axes of the pulleys.

[0084] In an embodiment, including in the illustrated example, the lifting block system 1 includes a connection mechanism for each second lower block pulley assembly 14b and preferably for one or more first lower block pulley assemblies 14a, here a combined connection and rotation mechanism 16, which is configured to provide the connectability and disconnectability of the respective lower block pulley assemblies 14 relative to the lower block base 12 and which is also configured here to provide the rotatability of the respective lower block pulley assemblies 14 about the respective rotational axes S when connected relative to the lower block base 12. Alternatively, such a rotational function may be provided by a separate mechanism or may be omitted.

[0085] In an embodiment, including in the illustrated example, the connection mechanism 16 consists of the lower block base, particularly fixed to the lower block base, although the relevant bearings 21 may also be fixed to the lower block pulley assembly 14.

[0086] In an embodiment, including in the illustrated example, the connection mechanism 16 includes at least one shaft assembly 17, which includes one or more (here two) shaft elements 18, the shaft elements being aligned with the rotational axis S, and the shaft assembly 17 is adjustable between a retracted state and an extended state. In the extended state, as Figure 7 and Figure 8As shown, the shaft element 18 interconnects the respective lower block assembly 14 and the lower block base 12. In the retracted state, as Figure 11 and Figure 12 shown, the shaft element 18 releases the respective lower block pulley assembly 14 relative to the lower block base 12. In Figure 12 , it can be seen that the lower block base 12 does descend relative to the lower block pulley assembly 14.

[0087] In an embodiment, including in the illustrated example, in the extended state, each shaft element 18 extends through a corresponding shaft opening 19 in the respective lower block assembly 14 and / or through a corresponding shaft opening 20 in the lower block base 12, wherein, in the retracted state, the shaft element 18 is located outside at least one of the shaft openings 19, 20, preferably outside the shaft opening 19 of the lower block assembly 14. In the illustrated example, the shaft opening 19 of the lower block assembly 14 can be positioned between the shaft opening 20 of the lower block base and the shaft assembly 17 fixed here to the lower block base 12. Thus, the shaft element 18 can advantageously be connected to the lower block base 12 on both sides of the shaft opening 19 to achieve a particularly firm and stable connection.

[0088] By comparing Figure 7 and Figure 8 , it can be seen that when the lower block pulley assembly 14 is loaded (see Figure 7 ), the shaft element 18 is supported on the lower block pulley assembly 14 by a bearing 21, while when the lower block pulley assembly 14 is unloaded (see Figure 8 ), the shaft element is not supported on the bearing. Thus, when unloaded, the shaft element 18 can retract from the shaft openings 19 and 20 with substantially no friction or impact. Similarly, to reconnect the lower block pulley assembly 14, the shaft element 18 can pass through the shaft openings 19 and 20 again while the lower block pulley assembly 14 can remain unloaded and is only loaded again after the connection is completed.

[0089] In an embodiment, including in the illustrated example, the upper block assembly 5 is configured to block the suspended first lower block pulley assembly 14a from moving upward toward the upper block assembly 5 beyond an additional predetermined limit M (see Figure 6 ), the additional predetermined limit M being closer to the upper block assembly 5 than the predetermined limit L and thus generally at a higher level than the predetermined limit L. This can advantageously prevent the second lower block pulley assembly 14b from being tensioned during disconnection, especially without the need to actively position the first lower block pulley assembly 14a with high precision. In the illustrated example, the additional predetermined limit M corresponds to the downward side of the blocking member 25. The distance between the predetermined limit L and the additional predetermined limit M (here corresponding to the distance d shown in Figure 5 ) is selected according to the available clearance between the shaft element 18 and the corresponding shaft opening 19. In particular, inFigure 8 As can be seen, the shaft element 18 has been disengaged from the previous contact with the bearing 21 of the shaft opening 19 (as Figure 7 shown), so that the shaft element 18 can be axially retracted from the shaft opening 19 substantially strain-free. In the illustrated example, the distance d between the limits L and M corresponds to approximately half of the available clearance in the corresponding direction (i.e., typically the height direction), so that, in Figure 8 what is seen, the shaft element 18 is approximately vertically centered within the bearing 21. Although a configuration involving an additional predetermined limit M is preferred, as an alternative, the above-mentioned clearance can be enlarged, for example, such that the position control of the winch 10 is sufficient to maintain a substantially strain-free arrangement.

[0090] In an embodiment, including in the illustrated example, the dimensions and / or shapes of the corresponding shaft openings 19 of the shaft element 18 and the lower block pulley assembly 14 are designed to provide a clearance therebetween when the shaft assembly 17 is in the extended state, while also providing a substantially mating interface F therebetween along a partial circumference of the shaft element 18 and the shaft opening 19 (represented by double dashed lines in Figure 10 what is seen) so as to transfer a load therebetween during use.

[0091] In an embodiment, including in the illustrated example, when the shaft assembly 17 is in the extended state, the section 27 of the shaft element 18 extending into the shaft opening 19 of the lower block pulley assembly 14 and the shaft opening 19 itself have mutually different cross-sectional shapes, in particular having mutually corresponding radii, here starting from the axis of rotation S and only along a finite circumferential portion including a part (here the bottom part), which is configured to provide the load-bearing interface F, as Figure 10 shown. It should be understood that if a similar shaft assembly is fixed to the lower block pulley assembly 14 instead of the lower block base 12, then typically the top part rather than the bottom part is configured to provide such a load-bearing interface.

[0092] In Figure 9 what is seen, it can be seen that the relevant section 27 is here an intermediate section, which extends between a proximal section 26 providing a connection to other parts of the shaft assembly 18 and a distal section 28 extending into the shaft opening 20 of the lower block base 12 at the time of connection. The smaller radius of the radius of the intermediate section 27 here corresponds to the total radius of the distal section 28, while the larger radius of the radius of the lower intermediate section 27 here corresponds to the total radius of the proximal section 26.

[0093] In an embodiment, including in the illustrated example, the shaft opening 19 in the lower block pulley assembly 14 is provided with a bearing 21 to reduce the rotational friction between the shaft opening 19 and the shaft element 18 when the shaft assembly 17 is in the extended state, particularly the rotational friction about the rotational axis S. Alternatively or additionally, such a bearing can be arranged on a section 27 of the shaft element 18 that extends into the shaft opening 19 of the lower block pulley assembly 14 when the shaft assembly 17 is in the extended state. The bearing 21 is mainly used here to facilitate smooth and durable rotation about the rotational axis S when the lower block pulley assembly 14 is connected to the lower block base 12 and loaded by the weight of the lower block base 12, and possibly further loaded by a load suspended from the lower block base 12.

[0094] In an embodiment, including in the illustrated example, the lifting block system 1 includes at least one motor 22 and / or gearbox 33, which is at least coupleably connected to the shaft element 18 for adjusting the shaft assembly 17 between the retracted state and the extended state by the drive of the motor 22 and / or gearbox 33. The motor 22 and / or gearbox 33 is preferably fixed to the lower block base 12, for example by a housing 30 as Figure 14 shown.

[0095] In an embodiment, including in the illustrated example, a plurality (here two) of shaft elements 18 are coupled to the same motor 22 and / or gearbox 33 in at least one motor 22 and / or gearbox 33, particularly for synchronously adjusting the plurality of shaft elements 18 between the retracted state and the extended state, where in particular, the plurality of shaft elements 18 are included by the same shaft assembly 17 and / or for connection to the same lower block pulley assembly 14 and / or alignment with the same axis (such as the rotational axis S). Additionally, the gearbox 33 can include one or more bevel gears, particularly for providing a right-angle drive, the input shaft of which extends at a right angle to two output shafts connected to the shaft element 18, as Figure 11 and Figure 12 shown. Although the gearbox 33 is shown here, alternatively, the shaft element 18 can also be directly driven by, for example, a motor and / or a manual operating tool, i.e., without an intermediate transmission.

[0096] In an embodiment, including in the illustrated example, the motor 22 and / or the gearbox 33 are coupled to the shaft element 18 by a conversion mechanism 23 configured to convert the rotation of the output shaft of the motor 22 and / or the gearbox 33 into an axial translation of the shaft element 18, here along the axis of rotation S. The conversion mechanism 23 here includes a threaded interface between the shaft element 18 and a threaded drive bolt 32 fixed to the output shaft of the motor 22. In the illustrated example, a nut 34 is fixed to the shaft element 18 to provide the threaded interface with the threaded drive bolt 32. Alternatively, the shaft element 18 itself may have internal threads. The conversion mechanism 23 here also includes an axial guiding structure 31 between the shaft element 18 and the housing 30, at least a portion of the shaft element 18 being received in the housing 30, the axial guiding structure 31 being configured to enable movement between the shaft element 18 and the housing 30 along the axis of rotation S while inhibiting rotational movement between them about the axis of rotation S. The housing 30 here is fixed to the lower block base 12.

[0097] More generally, in the lifting block system 1, it is preferred to provide various guiding structures 35.1, 35.2, 35.3 (also collectively referred to herein as 35), in particular centering structures, to guide the mutual positioning of mutually movable elements. In the illustrated example: the guiding structure 35.2 guides the lower block pulley assembly 14 relative to the blocking member 25 of the upper pulley assembly 5; and the guiding structures 35.1 and 35.3 guide the lower block pulley assembly 14 relative to the lower block base 12 and / or the shaft assembly 17. Such guiding structures 35 may particularly include pairs of guiding surfaces that extend at an angle to each other to define a guiding space or path that tapers towards the desired position of the element to be guided. For the clarity of the drawings, not all such guiding structures 35 are provided with reference numerals in all the figures, and in view of the indicated guiding structures 35 and this specification, it should be understood where additional such guiding structures can be seen in the drawings. In Figure 3B which, the guiding structure 35.3 as shown in Figure 4B and Figure 13B is omitted, showing a possible variant. In Figure 15 which, the guiding structures 35.2 as shown in Figure 1 , Figure 2 , Figure 3A , Figure 4A , Figure 13A are omitted, showing a possible variant. In Figure 1 and Figure 2 which, the shape of the guiding structure 35.2 is slightly different compared to the corresponding guiding structure 35.2 in Figure 3A , Figure 4A , Figure 13A although their functions are substantially the same, which illustrates possible variations.

[0098] As Figure 14As shown, a flexible coupling 29 is provided here between the motor 22 and / or the gearbox 33 and the conversion mechanism 23 to address possible alignment defects.

[0099] Although the present invention has been explained using examples of embodiments and drawings herein, these do not limit the scope of the present invention as defined by the claims. Those skilled in the art will understand that many variations, combinations, and extensions are possible. For example, the lifting assembly can be used on land and / or installed on land-based vehicles. All such variations are included within the scope of the present invention as defined by the claims.

[0100] List of Reference Numerals

[0101] 1. Lifting Block System

[0102] 2. Lifting Load

[0103] 3. Sling

[0104] 4. Lifting Rigging

[0105] 5. Upper Block Assembly

[0106] 6. Upper Block Pulley

[0107] 7. Lower Block Subsystem

[0108] 8. Lifting Assembly

[0109] 9. Lifting Arm

[0110] 10. Winch

[0111] 11. Ship or Barge

[0112] 12. Lower Block Base

[0113] 13. Lifting Hook

[0114] 14. Lower Block Pulley Assembly

[0115] 14a. First Lower Block Pulley Assembly

[0116] 14b. Second Lower Block Pulley Assembly

[0117] 15. Lower Block Pulley

[0118] 16. Combined Connecting and Rotating Mechanism

[0119] 17. Shaft Assembly

[0120] 18. Shaft Element

[0121] 19. Shaft Opening in Lower Block Pulley Assembly

[0122] 20. Shaft Opening in Lower Block Base

[0123] 21. Bearing

[0124] 22. Motor

[0125] 23. Conversion mechanism

[0126] 24a. Upper block engaging surface of the first lower block pulley assembly

[0127] 24b. Upper block engaging surface of the second lower block pulley assembly

[0128] 25. Blocking member

[0129] 26. Proximal section of the shaft element

[0130] 27. Intermediate section of the shaft element

[0131] 28. Distal section of the shaft element

[0132] 29. Flexible coupling

[0133] 30. Housing

[0134] 31. Axial guiding structure

[0135] 32. Threaded drive bolt

[0136] 33. Gearbox

[0137] 34. Nut

[0138] 35. Guiding structure (including 35.1, 35.2, 35.3)

[0139] d. Distance between the blocking member and the predetermined limit

[0140] F. Interface

[0141] L. Predetermined limit

[0142] M. Another predetermined limit

[0143] S. Axis of rotation.

Claims

1. A lifting block system for selectively lifting a lifting load using fewer or more slings of a lifting rigging, the system comprising: - an upper block assembly including a plurality of interconnected upper block pulleys configured to support the slings; and - a lower block subsystem, wherein the lower block subsystem includes: - a lower block base configured to suspend the lifting load therefrom; and - a plurality of lower block pulley assemblies each connectable to the lower block base and each including a lower block pulley suspendable by some of the slings on the upper block pulleys, wherein the plurality of lower block pulley assemblies includes one or more first lower block pulley assemblies and one or more second lower block pulley assemblies, wherein when the first and second lower block pulley assemblies are connected to the lower block base and are pulled upwardly toward the upper block assembly by shortening the slings, the upper block assembly is configured to block upward movement of the suspended second lower block pulley assembly toward the upper block assembly while allowing the suspended first lower block pulley assembly and the connected lower block pulley base to move upwardly toward the upper block assembly such that the second lower block pulley assembly can be unloaded by pulling the first lower block pulley assembly and the connected lower block base upwardly toward the upper block assembly beyond a predetermined limit, wherein the unloaded second lower block pulley assembly can be disconnected from the lower block base, thereby reducing the number of slings by which the lower block base is suspended from the upper block assembly.

2. The lifting block system according to claim 1, comprising, for each of the second lower block pulley assemblies and preferably for one or more of the first lower block pulley assemblies, a connection mechanism configured to provide connectivity and disconnectivity of the respective lower block pulley assembly relative to the lower block base.

3. The lifting block system according to claim 2, wherein the connection mechanism is further configured to provide rotatability of the respective lower block pulley assembly relative to the lower block base about a respective axis of rotation when connected.

4. The lifting block system according to claim 2 or 3, wherein the connection mechanism is included by the lower block base, in particular fixed to the lower block base.

5. The lifting block system according to any one of claims 2 - 4, wherein the connection mechanism includes at least one shaft assembly including one or more shaft elements, the shaft assembly being adjustable between a retracted state and an extended state, wherein in the extended state the shaft elements interconnect the respective lower block pulley assembly and the lower block base, and wherein in the retracted state the shaft elements release the respective lower block pulley assembly relative to the lower block base.

6. The lifting block system according to claim 5, wherein In the extended state, each said shaft element extends through a corresponding shaft opening in the respective lower block pulley assembly and / or through a corresponding shaft opening in the lower block base, wherein in the retracted state, the shaft element is located outside at least one of the shaft openings, preferably outside the shaft openings of the lower block assembly.

7. The lifting block system according to claim 6, wherein, the dimensions and / or shapes of the shaft element and the corresponding shaft opening of the lower block pulley assembly are designed to provide a clearance therebetween when the shaft assembly is in the extended state, while also providing a substantially mating interface therebetween along a partial circumference of the shaft element and the shaft opening to transfer a load therebetween during use.

8. The lifting block system according to claim 7, wherein, when the shaft assembly is in the extended state, the section of the shaft element extending into the shaft opening of the lower block pulley assembly and the shaft opening itself have mutually different cross-sectional shapes, particularly only along a limited circumferential portion, including the portion configured to provide the load-bearing interface F, having mutually corresponding radii.

9. The lifting block system according to any one of claims 6-8, wherein, when the shaft assembly is in the extended state, the section of the shaft element extending in the shaft opening of the lower block pulley assembly and / or the shaft opening itself is provided with a bearing to reduce the rotational friction between the shaft opening and the shaft element when the shaft assembly is in the extended state.

10. The lifting block system according to any one of claims 5-9, comprising at least one motor and / or gearbox, which is coupled to, at least capable of being coupled to, the shaft element for adjusting the shaft assembly between the retracted state and the extended state by driving of the motor and / or gearbox.

11. The lifting block system according to claim 10, wherein, a plurality of shaft elements are coupled to the same motor and / or gearbox in the at least one motor and / or gearbox, particularly for synchronously adjusting the plurality of shaft elements between the retracted state and the extended state, wherein in particular, the plurality of shaft elements are included by the same shaft assembly and / or are for connection to the same lower block pulley assembly and / or are aligned with the same axis of rotation.

12. The lifting block system according to claim 10 or 11, wherein, the motor and / or gearbox is coupled to the shaft element by a conversion mechanism configured to convert the rotation of the output shaft of the motor and / or gearbox into an axial translation of the shaft element.

13. The lifting block system according to any one of the preceding claims, wherein, the upper block assembly is configured to block the upward movement of the suspended first lower block pulley assembly towards the upper block assembly beyond a further predetermined limit closer to the upper block assembly than the predetermined limit, particularly in order to prevent the second lower block pulley assembly from being tensioned during its disconnection.

14. A lifting assembly for lifting a load using fewer or more slings of a lifting tackle selectively, comprising a lifting block system according to any one of the preceding claims and the lifting tackle.

15. The lifting assembly according to claim 14, comprising a lifting arm, such as a boom or an A-frame, wherein the lifting block system is suspended from the lifting arm, and wherein the lifting assembly preferably comprises one or more winches engaged with the lifting tackle for adjusting the length of the slings.

16. A ship or barge provided with the lifting assembly according to claim 14 or 15, particularly for offshore lifting operations.

17. A method of adjusting the effective number of slings in a lifting assembly, which comprises: - providing a lifting assembly according to claim 15; - with the second lower block pulley assembly connected to the lower block base, using the lifting tackle to pull the first lower block pulley assembly and the connected lower block base upwards towards the upper block assembly beyond a predetermined limit, thereby unloading the second lower block pulley assembly and disconnecting the unloaded second lower block pulley assembly from the lower pulley base, thereby reducing the effective number of slings; and / or - with the second lower block pulley assembly disconnected from the lower block base, connecting the second lower block pulley assembly to the lower block base, particularly when the lower block base is suspended from the upper block assembly by the lifting tackle and the first lower block pulley assembly is positioned beyond the predetermined limit towards the upper block assembly, thereby increasing the effective number of slings.

18. Use of a lifting block system according to any one of claims 1 to 13, a lifting assembly according to claim 14 or 15, and / or a ship or barge according to claim 16 for offshore lifting operations, particularly as part of an offshore wind turbine installation operation.

Images