Pitching boom crane with single-strand, two-strand or three-strand threading configuration

Abstract

A pitching boom crane (1) comprising:-a hoisting winch (2) coupled to a hoisting cable (20); -a pitch boom (10) provided with a boom end (11) on which at least two pulleys (32, 35) are mounted; -a stringing block (4) held by the hoisting cable and comprising a stringing pulley (41); and-a set of means for performing a threading change between a single-strand configuration, a two-strand configuration and a three-strand configuration, the set of means comprising a support for supporting the threading block in a fixed position in order to be able to operate the hoisting winch downward in order to loosen the hoisting cable, and an auxiliary traction system (6) for pulling the hoisting winch downward in order to loosen the hoisting cable. The auxiliary traction system is mounted on the pitching boom and is used for pulling the free end (21) of the lifting cable.

Description

Technical Field

[0001] The present invention relates to a pitch boom crane, which is provided with a device that allows for changes in the threading of its lifting cable among three threading configurations: a single-strand configuration, a two-strand configuration, and a three-strand configuration.

[0002] The present invention also relates to a rope threading method that allows for rope threading variations in the lifting cables of a pitch boom crane. Background Technology

[0003] Conventionally, a pitch boom crane includes a pitch boom with a boom end and boom outriggers, which are rotatably hinged about a horizontal axis at the top of the mast, allowing the boom to be raised and lowered. Additionally, the crane includes a hoisting winch, typically positioned on a sub-boom and connected to a hoisting cable that passes over at least one boom pulley positioned at the boom end to support a rope block equipped with a hooking member for engaging a load; the rope block includes a rope pulley under which the hoisting cable can pass.

[0004] For example, it is further known from document EP2411317B1 that there are two rope threading configurations, which are as follows:

[0005] - Single-strand configuration, in which the free end of the lifting cable is fastened to the rope block at the exit of the boom pulley, so that the rope block is suspended by a single strand of lifting cable.

[0006] - A two-strand configuration in which the lifting cable passes under the rope pulley at the exit of the boom pulley, and the free end of the lifting cable is secured to an anchor point located at the end of the boom.

[0007] Increasing the number of shares allows for heavier loads, thus requiring a three-share configuration, as is known from US 1,436,608.

[0008] However, the problem lies in moving the hoisting cable (and especially its free end) to position itself in one of the cable-threading configurations or another. In fact, hoisting cables are heavy, rigid, and therefore difficult to maneuver, especially on high-powered cranes that are designed to lift heavy loads and therefore require particularly thick, heavy, and rigid hoisting cables. Summary of the Invention

[0009] One of the objectives of this invention is to facilitate changes in the operation of the threading system, particularly among three threading configurations: a single-strand configuration, a two-strand configuration, and a three-strand configuration.

[0010] Therefore, the present invention provides a pitching jib crane, which includes: a hoisting winch connected to a hoisting cable having a free end, the hoisting winch being operable upward to raise the free end of the hoisting cable and operable downward to lower the free end of the hoisting cable; and a pitching jib having a jib end, on which a main pulley and a secondary pulley are mounted, the hoisting cable passing over the main pulley.

[0011] The tilting jib crane also includes a rope block with a hooking device for catching the load (i.e., the load suspended below the rope block and which must be transported / lifted / moved). The rope block is held by a lifting cable and has a rope pulley under which the lifting cable can pass. Thus, by activating the lifting winch, the rope block is raised or lowered individually or together with the load it suspends.

[0012] The tilting boom crane includes a set of devices for changing the hoisting cable threading between three threading configurations:

[0013] - Single-strand configuration, in which the free end of the lifting cable is fastened to the rope-threading block at the outlet of the main pulley, so that the rope-threading block is suspended by a single strand of lifting cable;

[0014] - Two-strand configuration, in which the lifting cable passes under the rope-passing pulley at the outlet of the main pulley, and the free end of the lifting cable is secured to an anchor point set at the end of the boom, so that the rope-passing block is suspended by the two lifting cables.

[0015] - A three-strand configuration in which, at the exit of the main pulley, the lifting cable passes under the rope-passing pulley, then rises to pass over the auxiliary pulley, and finally the free end of the lifting cable is secured to the rope-passing block, so that the rope-passing block is suspended by the three-strand lifting cable.

[0016] Therefore, this tilting boom crane allows for three rope configurations, which the crane operator can select based on the weight of the load. It should be noted that regardless of the rope configuration (in other words, in all three configurations), the lifting cable passes over the main pulley, while in the three-strand configuration it passes over the auxiliary pulley.

[0017] This group of devices includes at least:

[0018] - A support member for holding the rope block in a fixed position so that the hoisting winch can be operated downward to slack the hoisting cable while keeping the rope block in its fixed position.

[0019] - An auxiliary traction system, which is at least partially mounted on the pitch boom and configured to pull the free end of the lifting cable.

[0020] Therefore, this invention proposes a method to support the rope block in a fixed position such that its weight is borne or supported by a support member, and thus, when it is necessary to manipulate and move the hoisting cable between two rope configurations, rope changes can be made without being hindered or constrained by the weight of the rope block. Once the rope block is supported by the support member, the hoisting cable can be slackened (by operating the hoisting winch downwards), and thus it is easier to unhook, pull, manipulate, and hook the hoisting cable.

[0021] Furthermore, an auxiliary traction system is proposed that provides pulling on the free end of the hoisting cable, such that at least a portion of the cable's weight is borne and controlled by the auxiliary traction system to facilitate operator maneuvering. It should be noted that when using the auxiliary traction system to pull the free end of the hoisting cable, the hoisting winch needs to be operated parallel downwards to unfold the cable, thus accompanied by movement.

[0022] Based on one characteristic, the support component is selected from:

[0023] - Ground support components, on which rope blocks can be placed; and

[0024] - At least one sling having a given length, and the at least one sling being secure to the boom end and to the rope block so as to suspend the rope block below the boom end.

[0025] Therefore, the rope block can be lowered to rest on ground supports, thus allowing the previously slack lifting cable to be manipulated from the ground. Alternatively, the rope block can be suspended below the end of the boom by means of at least one sling, thus allowing the previously slack lifting cable to be manipulated at a certain height.

[0026] According to one possibility, at least one sling consists of a single sling.

[0027] According to another possibility, at least one sling consists of two slings designed to be fastened to each side of the rope block.

[0028] In addition, instead of a single sling, two slings can be used, with one sling fastened on each side of the rope block, to promote the balance of the rope block suspended by the two slings during operation.

[0029] According to one possibility, the auxiliary traction system includes an auxiliary cable having a given length and which can be secured to the free end of the lifting cable so that the free end of the lifting cable can be pulled by means of the auxiliary cable.

[0030] Such an auxiliary cable will make it easy to reach the free end of the lifting cable, making the free end of the lifting cable easier to pull and manipulate.

[0031] According to another possibility, the auxiliary traction system includes at least one auxiliary pulley mounted on the end of the boom, and an auxiliary cable passing over the at least one auxiliary pulley.

[0032] Such auxiliary pulleys allow the auxiliary cable to be guided or oriented to avoid obstacles specific to the crane structure, and thus prevent the auxiliary cable from scraping against scrap metal. The auxiliary pulleys also help to support the weight of both the auxiliary cable and the lifting cable, making it easier to pull the free end of the lifting cable.

[0033] In a particular embodiment, the auxiliary traction system includes a traction actuator coupled to an auxiliary cable, such as, for example, a winch.

[0034] In this embodiment, the auxiliary traction system is an assisting or motorized system that enables the auxiliary cable to be pulled by the traction actuator, and thus the lifting cable. This auxiliary traction system may, for example, integrate a winch, elevator, winch, or winch frame.

[0035] Alternatively, the auxiliary traction system is a manual system that allows the auxiliary cable to be pulled by hand, and thus the lifting cable. Such a manual solution is well-suited for small cranes with lifting cables of small cross-section, and is therefore manually operable, allowing traction to be performed by the operator, preferably by providing one or more pulleys to return the traction cable, thus facilitating manual traction.

[0036] Of course, one or more pulleys can also be provided in the assist system or motor system to allow the traction cable to return.

[0037] According to another possibility, the crane may include at least one auxiliary pulley mounted on the end of the boom and positioned below and rear of the main pulley. Where applicable, the auxiliary pulley is positioned below an auxiliary pulley.

[0038] The auxiliary pulley will allow the traction cable to extend along the auxiliary path, passing under the auxiliary pulley and then over the secondary pulley, so as to finally hook onto the free end of the lifting cable, so that it can be configured into a three-strand configuration by pulling the free end of the lifting cable.

[0039] In a particular embodiment, a set of devices includes: an anchoring member adapted to be fastened to a lifting cable; and at least one flexible connector that allows the anchoring member to be connected to a pulley or the free end of the lifting cable to be connected to a pulley or the anchoring member.

[0040] Such anchoring components thus allow for the formation of fixed points on the lifting cable, enabling easier movement of the rope block during configuration changes, particularly when the rope block has previously been placed on ground supports and the free end of the lifting cable has been manipulated / disengaged. Flexible connections allow the rope block or the free end of the lifting cable to be supported.

[0041] It may also have a flexible connector that connects the anchoring member to the rope block to bear the weight of the rope block, and / or a flexible connector that connects the free end of the lifting cable to the rope block or to the anchoring member to make it easier for the operator to manipulate the free end (another flexible connector if necessary).

[0042] The present invention also relates to a rope threading method for varying the hoisting cable of a pitching boom crane as described above, wherein the rope threading method includes at least:

[0043] - The rope block is supported in a fixed position by a support member so that the hoisting winch can be operated downward to slack the hoisting cable while leaving the rope block in its fixed position.

[0044] - The configuration of the hoisting cable can be changed by using an auxiliary traction system to pull the free end of the hoisting cable or by operating the hoisting winch upwards.

[0045] When changing from a single-strand configuration to a two-strand or three-strand configuration, the auxiliary traction system is used to pull the free end of the lifting cable to go under the rope pulley and secure it to the anchor point located at the end of the boom (for a two-strand configuration) or to go over the auxiliary pulley and then secure it to the rope block (for a three-strand configuration).

[0046] When changing from a two-strand or three-strand configuration to a single-strand configuration, the hoisting winch is operated upward to wind the hoisting cable so that it no longer passes under the rope threading pulley, and then the hoisting cable is secured to the rope threading block (for a single-strand configuration).

[0047] In a specific embodiment, for the threading change from a single-strand configuration to a final configuration (which is a two-strand or three-strand configuration), the threading method includes at least the following steps:

[0048] - The rope block is supported by the support members, and the hoisting winch is operated downward to slack the hoisting cable while leaving the rope block in its fixed position.

[0049] - Disconnect the free end of the lifting cable from the rope-threading block, and then pass the lifting cable under the rope-threading pulley;

[0050] - An auxiliary cable of a given length is secured to the free end of the lifting cable, the auxiliary cable being integrated into the auxiliary traction system; and

[0051] - The free end of the lifting cable is pulled by an auxiliary traction system via an auxiliary cable, and then the free end of the lifting cable is tightened according to the final configuration;

[0052] - Disconnect the auxiliary cable from the free end of the lifting cable.

[0053] After the rope block is supported by the support members, and before the free end of the lifting cable is unhooked from the rope block, it may be necessary to pull the lifting cable to unhooke the free end of the lifting cable from the rope block.

[0054] In fact, in some cases, even if the rope block is supported and even if the hoisting cable has been slackened by operating the hoisting winch downwards, the weight of the upstream hoisting cable causes it to leave the free end of the hoisting cable in a taut state on the rope block.

[0055] According to one possibility, the lifting cable is pulled through the following steps, which are referred to as the release steps:

[0056] - The temporary anchor point of the lifting cable is secured to the temporary anchor point of the crane via a chain hoist type mechanism;

[0057] - Operate the chain crane to pull the temporary anchor point of the lifting cable in order to release the lifting cable and to detach the free end of the lifting cable from the rope block.

[0058] In the first embodiment, after the rope-threading block has been lowered to the ground support, the rope-threading block is supported by the support (which is a ground support), and the rope-threading method includes:

[0059] - After the hoisting cable has been passed under the rope-threading pulley and before the auxiliary cable is tightened, the anchoring member is fastened to the hoisting cable and at least one flexible connection is arranged to connect the anchoring member to the rope-threading block, or the at least one flexible connection connects the free end of the hoisting cable to the rope-threading block or to the anchoring member. Then the hoisting winch is operated upward to raise the rope-threading block, and the anchoring member is configured to hold the rope-threading block by the hoisting cable.

[0060] - Once in final configuration, remove the anchoring components from the lifting cable (and remove the flexible connectors).

[0061] Therefore, there may be a flexible connector that connects the anchoring member to the rope block to bear the weight of the rope block, and / or a flexible connector that connects the free end of the lifting cable to the rope block or to the anchoring member to make it easier for the operator to manipulate the free end (another flexible connector if necessary).

[0062] According to one possibility, when the anchoring member is tightened to the lifting cable:

[0063] - A flexible connector is arranged to fasten the anchoring member to the descending section of the lifting cable located between the main pulley and the threading pulley, so as to connect the anchoring member to the threading block, and fasten the free end of the lifting cable to the descending section of the lifting cable or to the anchoring member (directly or via another flexible connector), and then suspend the threading block on the anchoring member via the flexible connector during the raising of the threading block;

[0064] - Alternatively, the anchoring member is fastened to the terminal section of the lifting cable located between the rope-threading pulley and the free end of the lifting cable. The anchoring member abuts against the rope-threading block during the raising of the rope-threading block, and a flexible connector is arranged to connect the free end of the lifting cable to the rope-threading block or to the anchoring member.

[0065] In the second embodiment, the rope block is supported by a support member including at least one sling (possibly two slings) fastened to the boom end and the rope block, such that the rope block is suspended below the boom end.

[0066] In this second embodiment, starting with a single-strand configuration, the rope block is supported by at least one sling (possibly balanced by two slings) through the following operation:

[0067] - Operate the winch upwards to raise it to the given high position;

[0068] - Secure at least one sling (possibly two slings) between the rope block and the end of the boom, at a high position such that at least one sling is slack at that high position (possibly both slings are slack).

[0069] - Operate the hoisting winch downwards, at least until at least one sling is tensioned and supports the rope block (possibly until both slings are tensioned and support the rope block).

[0070] According to the first variant, the final configuration is a two-strand configuration, and in this case, the auxiliary cable is directly fastened to the free end of the lifting cable, such that the free end of the lifting cable is directly pulled by the auxiliary cable to the anchor point to be fastened there, so as to be in a two-strand configuration.

[0071] According to the second variation, the final configuration is a three-strand configuration, and in this case, the auxiliary cable extends along the auxiliary path, passes under the auxiliary pulley mounted on the end of the boom, and then passes over the secondary pulley so that it is finally hooked onto the free end of the lifting cable; and the free end of the lifting cable is pulled by the auxiliary cable, and thus passes over the secondary pulley so that it is finally secured to the rope block, thus being in a three-strand configuration.

[0072] In this second embodiment, anchoring members are not required.

[0073] According to another possibility, for the threading change from an initial configuration (which is a two-strand or three-strand configuration) to a single-strand configuration, the threading method includes at least the following steps:

[0074] - The rope block is supported by the support members, and the hoisting winch is operated downward to slack the hoisting cable while leaving the rope block in its fixed position.

[0075] - Based on the initial configuration, the free end of the lifting cable will be unhooked;

[0076] - Operate the hoisting winch upward to wind the hoisting cable so that it no longer passes under the rope pulley;

[0077] - Based on the single-strand configuration, secure the free end of the lifting cable to the rope-threading block.

[0078] Regarding the steps for disengaging the free end of the lifting cable according to the initial configuration:

[0079] - If the initial configuration is a two-strand configuration, the steps include disengaging the free end of the lifting cable from the anchor point located at the end of the boom;

[0080] - Alternatively, if the initial configuration is a three-strand configuration, the steps include unhooking the free end of the lifting cable from the rope block.

[0081] As previously described, after the rope block is supported by the support members and before the free end of the lifting cable is unhooked from the anchor point or the rope block, it may be necessary to pull the lifting cable to unhooke the free end of the lifting cable from the rope block. In this case, the release steps described above can be performed.

[0082] In a particular embodiment, the rope block is supported by a support member including at least one sling fastened to the boom end and the rope block, such that the rope block is suspended below the boom end.

[0083] This type of support, which uses at least one sling (and possibly two slings), is particularly suitable for changing the rope system from a two- or three-sling configuration to a single-sling configuration, in which case the lifting cable is secured to an anchor point located at the end of the boom (in a two-sling configuration) or looped around an auxiliary pulley located at the end of the boom (in a three-sling configuration).

[0084] The rope system can still be changed from a two- or three-strand configuration to a single-strand configuration using anchoring members associated with ground supports.

[0085] Advantageously, for the threading change from the initial configuration (which is a two-strand or three-strand configuration) to a single-strand configuration:

[0086] - Before unhooking the free end of the lifting cable according to the initial configuration, the free end of the lifting cable is secured to an auxiliary cable, which is integrated into the auxiliary traction system;

[0087] - When the hoisting winch is operated upward to retrieve the hoisting cable, the auxiliary traction system releases the auxiliary cable to follow the hoisting cable.

[0088] - Once in a single-strand configuration, the auxiliary cable is detached from the free end of the lifting cable.

[0089] Therefore, the auxiliary cable can accompany the lifting cable and partially support its weight, thus making the operation safer.

[0090] In another specific embodiment, for a rope threading change from a two-strand configuration to a three-strand configuration, the rope threading method includes at least the following steps:

[0091] - The rope block is supported by a support member, which includes at least one sling fastened to the boom end and the rope block, such that the rope block is suspended below the boom end.

[0092] - Operate the hoisting winch downwards to slack the hoisting cable while leaving the rope block in its fixed position;

[0093] - Disconnect the free end of the lifting cable from the anchor point;

[0094] - An auxiliary cable of a given length is secured to the free end of the lifting cable. This auxiliary cable is integrated into the auxiliary traction system and extends along an auxiliary path, passing under an auxiliary pulley mounted at the end of the boom, and then over a secondary pulley, so as to finally hook onto the free end of the lifting cable; and

[0095] - With the help of an auxiliary traction system, the free end of the lifting cable is pulled by an auxiliary cable to pass over the auxiliary pulley and finally secure to the rope block in a three-strand configuration;

[0096] - Disconnect the auxiliary cable from the free end of the lifting cable.

[0097] As previously described, after the rope block is supported by the support member and before the free end of the lifting cable is unhooked from the anchor point, it may be necessary to pull the lifting cable to unhooke the free end of the lifting cable from the rope block. In this case, the release step described above can be performed.

[0098] In another embodiment, for a rope threading change from a three-strand configuration to a two-strand configuration, the rope threading method includes at least the following steps:

[0099] - The rope block is supported by a support member, which includes at least one sling fastened to the boom end and the rope block, such that the rope block is suspended below the boom end.

[0100] - Operate the hoisting winch downwards to slack the hoisting cable while leaving the rope block in its fixed position;

[0101] - Disconnect the free end of the lifting cable from the rope block;

[0102] - Secure an auxiliary cable of a given length to the free end of the lifting cable, the auxiliary cable being integrated into the auxiliary traction system and passing under an auxiliary pulley mounted on the end of the boom;

[0103] - Operate the hoisting winch upward to retract the hoisting cable so that it no longer passes over the auxiliary pulley, and allow the auxiliary cable to pass over the auxiliary pulley to keep the free end of the hoisting cable.

[0104] - Secure the free end of the lifting cable to the anchor point located at the end of the boom for a two-strand configuration;

[0105] - Disconnect the auxiliary cable from the free end of the lifting cable.

[0106] As previously described, after the rope block is supported by the support members and before the free end of the lifting cable is unhooked from the anchor point or the rope block, it may be necessary to pull the lifting cable to unhooke the free end of the lifting cable from the rope block. In this case, the release steps described above can be performed. Attached Figure Description

[0107] Other features and advantages of the invention will become apparent upon reading the following detailed description of non-limiting examples of embodiments with reference to the accompanying drawings, in which:

[0108] Figure 1It is a schematic partial view of a pitch boom crane, with an enlarged view of the boom end (upper right) and an enlarged view of the main pulley and auxiliary pulley (lower right);

[0109] Figure 2 This is a schematic diagram illustrating the three steps (a1) to (a3) ​​of the rope threading change from a single-strand configuration to a two-strand configuration;

[0110] Figure 3 This illustrates the change in the threading from a single-strand configuration to a two-strand configuration. Figure 2 A schematic diagram of the three steps (a1) to (a3) ​​followed by the three steps (a4) to (a6);

[0111] Figure 4 This illustrates the change in the threading from a single-strand configuration to a two-strand configuration. Figure 3 A schematic diagram of the three steps (a4) to (a6) followed by the three steps (a7) to (a9);

[0112] Figure 5 It shows the basis and Figures 2 to 4 A schematic diagram of the three steps (b1) to (b3) of the alternative embodiment for the rope threading change from a single-strand configuration to a two-strand configuration, compared to the embodiment;

[0113] Figure 6 This illustrates the change in the threading from a single-strand configuration to a two-strand configuration. Figure 5 A schematic diagram of the three steps (b1) to (b3) followed by the three steps (b4) to (b6);

[0114] Figure 7 This illustrates the change in the threading from a single-strand configuration to a two-strand configuration. Figure 6 A schematic diagram of the three steps (b4) to (b6) followed by the three steps (b7) to (b9);

[0115] Figure 8 This illustrates the change in the threading from a single-strand configuration to a two-strand configuration. Figure 7 A diagram illustrating the final step (b10) following the three steps (b7) to (b9);

[0116] Figure 9 It shows the basis and Figures 2 to 4 Implementation examples and Figures 5 to 8 A schematic diagram of two steps (c1) to (c2) of the rope threading change from a single-strand configuration to a two-strand configuration in another variant embodiment compared to the embodiment;

[0117] Figure 10 This illustrates the change in the threading from a single-strand configuration to a two-strand configuration. Figure 9A schematic diagram of the three steps (c3) to (c5) following the two steps (c1) to (c2);

[0118] Figure 11 This illustrates the change in the threading from a single-strand configuration to a two-strand configuration. Figure 10 A schematic diagram of the three steps (c3) to (c5) followed by the three steps (c6) to (c8);

[0119] Figure 12 This is a schematic diagram illustrating the three steps (d1) to (d3) of the rope threading change from a single-strand configuration to a three-strand configuration;

[0120] Figure 13 This illustrates the change in the threading from a single-strand configuration to a three-strand configuration. Figure 12 A schematic diagram of the three steps (d1) to (d3) followed by the three steps (d4) to (d6);

[0121] Figure 14 This illustrates the change in the threading from a single-strand configuration to a three-strand configuration. Figure 13 A schematic diagram of the three steps (d4) to (d6) followed by the three steps (d7) to (d9);

[0122] Figure 15 This is a schematic diagram showing the three steps (e1) to (e3) of the rope threading change from a two-strand configuration to a three-strand configuration;

[0123] Figure 16 This illustrates the change in rope threading from a two-strand configuration to a three-strand configuration. Figure 15 A schematic diagram of the three steps (e1) to (e3) followed by the three steps (e4) to (e6); and

[0124] Figure 17 This illustrates the change in rope threading from a two-strand configuration to a three-strand configuration. Figure 16 A schematic diagram of the three steps (e4) to (e6) followed by the three steps (e7) to (e9). Detailed Implementation

[0125] refer to Figure 1 The pitch boom crane 1 includes a pitch boom 10 with a boom end 11 and boom legs 12, which is rotatably hinged about a horizontal axis at the top of a mast 13. The pitch boom crane 1 also includes a sub-boom 14 mounted at the top of the mast 13 and radially opposite the pitch boom 10.

[0126] The tilting boom crane 1 includes a hoisting winch 2 connected to a hoisting cable 20 having a free end 21, and the hoisting winch 2 can be mounted on a secondary boom 14.

[0127] The boom end 11 is sequentially equipped with a high pulley 31 and a main pulley 32. Regardless of the rope threading configuration, the lifting cable 20 passes over both the high pulley and the main pulley. The high pulley 31 is located above and behind the main pulley 32, so the lifting cable 20 first passes over the high pulley 31 and then over the main pulley 32. It is conceivable that, depending on the length of the pitch boom 10, at least one other pulley 33 is provided, positioned on the pitch boom 10 between the boom end 11 and the boom outriggers 12, and the lifting cable 20 passes over this at least one other pulley.

[0128] The boom end 11 is also equipped with a secondary pulley 35 (only on the end of the boom). Figure 1 (As clearly shown in the diagram), the lifting cable 20 only passes over the auxiliary pulley in a three-strand configuration. In the illustrated example, the auxiliary pulley 35 is mounted coaxially with the main pulley 32; this is because the auxiliary pulley... Figures 2 to 17 The reason it is not visible in the middle is that the secondary pulley 35 is located below and in front of the high pulley 31.

[0129] The boom end 11 has an anchor point 15, which is located behind the main pulley 32 and below the high pulley 31.

[0130] The hoisting winch 2 can be operated in the upward direction to raise the free end 21 of the hoisting cable 20, and the hoisting winch can be operated in the downward direction to lower the free end 21 of the hoisting cable 20.

[0131] The tilting boom crane 1 includes a rope block 4, which is provided with a hooking member 40 (conventionally a hook) for hooking a load. The rope block 4 is held by a lifting cable 20 and includes a rope pulley 41 under which the lifting cable 20 can pass. The rope block 4 includes a frame 42, within which the rope pulley 41 is housed, and an upper hooking point 43 is provided on the frame. In a variant suitable for a four-strand configuration (not described below), the rope block 4 will include another rope pulley.

[0132] This type of tilting boom crane 1 may have three rope threading configurations, namely:

[0133] - Single stock allocation (in) Figure 1 , Figure 2 Step (a1) Figure 5 Step (b1) and Figure 9 As can be seen in step (c1), in this single-strand configuration, at the outlet of the main pulley 32, the free end 21 of the lifting cable 20 is fastened to the rope block 4 (and more precisely, to the upper attachment point 43), such that the rope block 4 is suspended by the single-strand lifting cable 20.

[0134] - Two-stock configuration (in) Figure 4 Step (a9) Figure 8 Step (b10) Figure 11 Step (c8) and Figure 15 As can be seen in step (e1), in this two-strand configuration, at the outlet of the main pulley 32, the lifting cable 20 passes under the rope pulley 41, and the free end 21 of the lifting cable is fastened to the anchor point 15 provided on the boom end 11, so that the rope block 4 is suspended by the two lifting cables 20.

[0135] - Three-stock allocation (in) Figure 14 Step (d9) and Figure 17 As seen in step (e9), in this three-strand configuration, at the outlet of the main pulley 32, the lifting cable 20 passes under the rope-passing pulley 41, then rises to pass over the auxiliary pulley 35, and finally the free end of the lifting cable is secured to the rope-passing block 4 (and more precisely, to the upper attachment point 43), so that the rope-passing block 4 is suspended by the three-strand lifting cable 20.

[0136] The tilting boom crane 1 includes a set of devices for changing the threading of the lifting cable 20 between three threading configurations.

[0137] The assembly includes supports 50 and 51 that allow the rope block 4 to be held in a fixed position so that the hoisting winch 2 can be operated downwards to slack the hoisting cable 20 while keeping the rope block 4 in its fixed position. Thus, the rope block 4, supported by the supports to remain in its fixed position, allows the hoisting winch 2 to be operated downwards without moving the rope block 4 (which remains in its fixed position), and consequently slacks the hoisting cable 20 and provides a degree of slack that allows it to be manipulated to change its configuration.

[0138] exist Figure 2 Steps (a2) and (a3) ​​and Figure 5 In the embodiments shown in steps (b2) and (b3), the support is a ground support 50, such as a bracket, on which the rope block 4 can rest after being lowered. Once the rope block 4 is resting on the ground support 50, the hoisting winch 2 can be operated downward without moving the rope block 4 (which remains on the ground support 50), and thus the hoisting cable 20 is slack and has a degree of slack.

[0139] exist Figure 10 Steps (c3) to (c5) Figure 12 Step (d3) Figure 13 Steps (d4) to (d6) Figure 15 Step (e3) and Figure 16In the embodiments shown in steps (e4) to (e6), the support includes at least one sling 51 of a given length, and the at least one sling can be secured to the boom end 11 and the rope block 4 (advantageously secured to an attachment point other than the upper attachment point 43) so as to suspend the rope block 4 below the boom end 11.

[0140] Advantageously, at least one sling 51 comprises two slings 51 of the same length, which can be secured to the boom end 11 and the rope block 4; wherein the right sling 51 is secured to the right side of the rope block 4 and the right side of the boom end 11, and the left sling 51 is secured to the left side of the rope block 4 and the left side of the boom end 11, so as to balance the suspension of the rope block 4 and keep it upright during operation.

[0141] Once the rope block 4 is suspended by the sling 51, the hoisting winch 2 can be operated downwards without moving the rope block 4 (which remains suspended), and thus the hoisting cable 20 is slack and has a degree of slack. In some cases, it may be advantageous and necessary to assist the hoisting cable 20 by reducing the upstream weight of the hoisting cable 20, for example by connecting the temporary anchor point of the hoisting cable 20 to the temporary anchor point of the crane via a chain hoist-type mechanism.

[0142] The sling 51 can be fastened to the end of the boom, located below the main pulley 32. When using two slings 51, the two slings 51 can be fastened to either side of the main pulley 32 or the auxiliary pulley 35.

[0143] The assembly includes an auxiliary traction system 6 mounted on the pitch boom 10, which allows the free end 21 of the lifting cable 20 to be pulled. In the illustrated version, the auxiliary traction system 6 includes an auxiliary cable 60 connected to a traction actuator 61, such as a winch. In a manual variant, the traction actuator 61 may be omitted, allowing the traction cable 60 to be pulled manually. The auxiliary cable 60 has a free end 62 that can be secured to the free end 21 of the lifting cable 20, allowing the lifting cable 20 to be pulled by pulling the traction cable 60, and allowing the lifting cable 20 to be held by holding the traction cable 60.

[0144] The auxiliary traction system 6 includes at least one auxiliary pulley 63 mounted on the boom end 11, and an auxiliary cable 60 passing over the at least one auxiliary pulley. The auxiliary pulley 63 is positioned behind the main pulley 32 and above the anchor point 15.

[0145] The auxiliary traction system 6 includes at least one auxiliary pulley 64, which is mounted on the boom end 11 and positioned below and behind the main pulley 32, and also below the auxiliary pulley 63. The utility of the at least one auxiliary pulley will be described later.

[0146] As described later in some steps of implementing the ground support 50, the assembly may also include an anchoring member 52 adapted to be fastened to the lifting cable 20, and the anchoring member is provided with at least one flexible connector 53 such that the anchoring member 52 can be connected to the rope block 4. The anchoring member 52 may be in the form of a stirrup or a yoke, which can be fixedly taut around the lifting cable 20. The flexible connector 53 may be in the form of a cable, chain, or rope.

[0147] The remainder of the description relates to a rope threading method for varying the threading of the lifting cable 20 of the aforementioned pitch boom crane 1, with several examples of embodiments provided. Figures 2 to 17 As shown in the image.

[0148] Figures 2 to 4 A first method for changing the threading from a single-strand configuration to a two-strand configuration is shown, and the method implements the steps (a1) to (a9).

[0149] exist Figure 2 In the first step (a1) shown, the lifting cable 20 is in its single-strand configuration, and the rope block 4 is suspended by the single-strand lifting cable 20.

[0150] exist Figure 2 In the second step (a2) shown, the hoisting winch is operated downward to lower the rope block 4 until it is supported in a fixed position by the ground support 50. Once the rope block 4 is supported by the ground support 50, the hoisting winch is operated downward further (or again) to slack the hoisting cable 20 while leaving the rope block 4 in its fixed position on the ground support 50.

[0151] exist Figure 2 In the third step (a3) ​​shown, the free end 21 of the lifting cable 20 is unhooked from the rope-threading block 4, then the lifting cable 20 is passed under the rope-threading pulley 41 and then exits from the rope-threading block 4. The lifting cable 20 thus has a terminal section 22 that extends from the rope-threading block 4 and is positioned between the rope-threading pulley 41 and the free end 21 of the lifting cable.

[0152] exist Figure 3In the fourth step (a4) shown, the anchoring member 52 is fastened to the lifting cable 20, and more precisely, the anchoring member 52 is fastened to the end section 22 of the lifting cable 20, and a flexible connector 53 is arranged to connect the free end 21 of the lifting cable 20 to the pulley 4 (or alternatively to the anchoring member 52).

[0153] exist Figure 3 In the fifth step (a5) shown, the hoisting winch is operated upward to raise the rope block 4. During the raising of the rope block 4, the anchoring member 52 holds the rope block 4 by the hoisting cable 20. In fact, while the hoisting winch pulls the hoisting cable 20 to raise the rope block 4, the anchoring member 52 abuts against the frame 42 of the rope block 4.

[0154] exist Figure 3 In the sixth step (a6) shown, the free end 62 of the traction cable 60 is attached to the flexible connector 53; the traction cable 60 passes over the auxiliary pulley 63 as a return line.

[0155] exist Figure 4 In the seventh step (a7) shown, the flexible connector 53 is detached from the rope threading block 4 (or alternatively from the anchoring member 52) while remaining attached to the free end 21 of the lifting cable 20. Then, the traction cable 60 is pulled, which pulls the flexible connector 53 and thus also pulls the free end 21 of the lifting cable 20. In other words, the free end 21 of the lifting cable 20 is pulled via the auxiliary cable 60 by means of the auxiliary traction system 6, and the flexible connector 53 is also pulled, and then, according to the two-strand configuration, the free end 21 of the lifting cable 20 is secured to the anchor point 15. While the traction cable 60 pulls the free end 21 of the lifting cable 20, the hoisting winch is actuated downwards in parallel to release the lifting cable 20, and thus the movement is accompanied by this action.

[0156] exist Figure 4 In the eighth step (a8) shown, the flexible connector 53 is detached from the free end 21 of the lifting cable 20 and removed (so that the auxiliary cable 60 is also unhooked from the lifting cable 20), and the lifting winch is operated downward to lower the rope block 4 and tension the terminal section 22 of the lifting cable 20.

[0157] exist Figure 4 In the ninth step (a9) shown, the anchoring member 52 is disassembled and removed from the lifting cable 20, and thus the lifting cable 20 is in its two-strand configuration, wherein the rope block 4 is suspended by the two strands of the lifting cable 20.

[0158] Figures 5 to 7 A second method for changing the rope threading from a single-strand configuration to a two-strand configuration is shown, and the method implements the steps (b1) to (b10).

[0159] exist Figure 5 In the first step (b1) shown, the lifting cable 20 is in its single-strand configuration, wherein the rope block 4 is suspended by the single-strand lifting cable 20.

[0160] exist Figure 5 In the second step (b2) shown, the hoisting winch is operated downward to lower the rope block 4 until it is supported in a fixed position by the ground support 50. Once the rope block 4 is supported by the ground support 50, the hoisting winch is operated downward again (or again) to slack the hoisting cable 20 while leaving the rope block 4 in its fixed position on the ground support 50.

[0161] exist Figure 5 In the third step (b3) shown, the free end 21 of the lifting cable 20 is unhooked from the rope-threading block 4, and then the lifting cable 20 is passed under the rope-threading pulley 41 and then exits from the rope-threading block 4. The lifting cable 20 thus has a terminal section 22 that extends from the rope-threading block 4 and is positioned between the rope-threading pulley 41 and the free end 21 of the lifting cable. The lifting cable 20 also has a descending section 23 positioned between the main pulley 32 and the rope-threading pulley 41. Then, the anchoring member 52 is fastened to the lifting cable 20, and more precisely, to the descending section 23, located directly above the rope-threading block 4, and a flexible connector 53 is arranged to connect the anchoring member 52 to the rope-threading block 4; the flexible connector 53 is in a released state because it is longer than the distance between the rope-threading block 4 and the anchoring member 52. The terminal section 22 is raised and secured above the anchoring member 52 to the descending section 23 of the lifting cable 20 or to the anchoring member 52. Therefore, the free end 21 of the lifting cable 20 is secured above the anchoring member 52 to the descending section 23 of the lifting cable 20 or to the anchoring member 52. Alternatively, the free end 21 of the lifting cable 20 is secured to the descending section 23 of the lifting cable 20 or to the anchoring member 52 via another flexible connector.

[0162] exist Figure 6 In the fourth step (b4) shown, the hoisting winch is operated upward to raise the rope block 4. During the raising of the rope block 4, the anchoring member 52 holds the rope block 4 by the hoisting cable 20. In fact, the rope block 4 is suspended from the anchoring member 52 by the flexible connector 53.

[0163] exist Figure 6 In the fifth step (b5) shown, the free end 62 of the traction cable 60 is attached to the free end 21 of the lifting cable 20; as previously described, the traction cable 60 passes over the auxiliary pulley 63.

[0164] exist Figure 6 In the sixth step (b6) shown, the terminal section 22 of the lifting cable 20 is disengaged from the descending section 23 of the lifting cable 20 or from the anchoring member 52; then, the terminal section 22 of the lifting cable 20 enters the release state while being held by the traction cable 60.

[0165] exist Figure 7 In the seventh step (b7) shown, the traction cable 60 is pulled, which in turn pulls the free end 21 of the lifting cable 20. In other words, the free end 21 of the lifting cable 20 is pulled by the auxiliary traction system 6 via the auxiliary cable 60, and then, according to the two-strand configuration, the free end 21 of the lifting cable 20 is secured to the anchor point 15. Simultaneously with the traction cable 60 pulling the free end 21 of the lifting cable 20, the hoisting winch is operated downwards in parallel to release the lifting cable 20, and this movement is thus accompanied by the action.

[0166] exist Figure 7 In the eighth step (b8) shown, the auxiliary cable 60 is detached from the lifting cable 20.

[0167] exist Figure 7 In the ninth step (b9) shown, the lifting winch is operated downward to lower the rope block 4 and tension the terminal section 22 of the lifting cable 20, which also causes the flexible connector 53 to loosen.

[0168] exist Figure 8 In the tenth step (b10) shown, the flexible connector 53 is removed from the rope block 4, and then the anchoring member 52 is removed from the lifting cable 20 and removed, and thus the lifting cable 20 is in its two-strand configuration, wherein the rope block 4 is suspended by the two strands of the lifting cable 20.

[0169] Figures 9 to 11 A third method for changing the threading from a single-strand configuration to a two-strand configuration is shown, and the method implements the steps (c1) to (c8).

[0170] exist Figure 9 In the first step (c1) shown, the lifting cable 20 is in its single-strand configuration, wherein the rope block 4 is suspended by the single-strand lifting cable 20; the rope block 4 is positioned at a given high position, positioned relatively high and close to the boom end 11.

[0171] exist Figure 9 In the second step (c2) shown, at least one sling 51 is secured between the rope block 4 and the boom end 11, with the rope block 4 positioned high such that at least one sling 51 is slack at that high position.

[0172] exist Figure 10In the third step (c3) shown, the hoisting winch is operated downwards until at least one sling 51 is tensioned and the rope block 4 is supported in a fixed position.

[0173] exist Figure 10 In the fourth step (c4) shown, once the rope block 4 is supported by at least one sling 51, the hoisting winch is operated downwards (or again) to slack the hoisting cable 20 while leaving the rope block 4 in its fixed position. Then, the free end 21 of the hoisting cable 20 is unhooked from the rope block 4, and the hoisting cable 20 is then passed under the rope pulley 41 and exits from the rope block 4. Then, the free end 62 of the traction cable 60 is attached to the free end 21 of the hoisting cable 20; as previously described, the traction cable 60 passes over the auxiliary pulley 63.

[0174] exist Figure 10 In the fifth step (c5) shown, the traction cable 60 is pulled, which in turn pulls the free end 21 of the lifting cable 20. In other words, the free end 21 of the lifting cable 20 is pulled by the auxiliary traction system 6 via the auxiliary cable 60, and then, according to the two-strand configuration, this free end 21 of the lifting cable 20 is secured to the anchor point 15. Simultaneously with the traction cable 60 pulling the free end 21 of the lifting cable 20, the hoisting winch is operated downwards in parallel to release the lifting cable 20, and this movement is thus accompanied by the action.

[0175] Of course, other methods can be used to move from step (c3) to step (c5), such as during step (c1) or (c2) connecting the free end 21 of the lifting cable 20 to the intermediate cable that passes under the rope pulley 41, and then during step (c4) hooking the free end 62 of the traction cable 60 to the intermediate cable, which would make it easier to connect to the lifting cable 20.

[0176] exist Figure 11 In the sixth step (c6) shown, the auxiliary cable 60 is detached from the lifting cable 20.

[0177] exist Figure 11 In the seventh step (c7) shown, the lifting winch is operated upward to raise the rope block 4 to a high position, which causes at least one sling 51 to slack.

[0178] exist Figure 11 In the eighth step (c8) shown, at least one sling 51 is detached from and removed from the rope block 4, and thus the lifting cable 20 is in its two-strand configuration, wherein the rope block 4 is suspended by the two-strand lifting cable 20.

[0179] Figures 12 to 14A method for changing the rope threading from a single-strand configuration to a three-strand configuration is shown, and the method implements the following steps (d1) to (d9).

[0180] exist Figure 12 In the first step (d1) shown, the lifting cable 20 is in its single-strand configuration, and the rope block 4 is suspended by the single-strand lifting cable 20; the rope block 4 is positioned at a given high position, positioned relatively high and close to the boom end 11.

[0181] exist Figure 12 In the second step (d2) shown, at least one sling 51 is secured between the rope block 4 and the boom end 11, with the rope block 4 positioned high such that at least one sling 51 is slack at that high position.

[0182] exist Figure 12 In the third step (d3) shown, the hoisting winch is operated downwards until at least one sling 51 is tensioned and the rope block 4 is supported in a fixed position.

[0183] exist Figure 13 In the fourth step (d4) shown, the traction cable 60 is arranged to extend along the auxiliary path, first passing over the auxiliary pulley 63, then under the auxiliary pulley 64, and then over the secondary pulley 35.

[0184] exist Figure 13 In the fifth step (d5) shown, the hoisting winch is operated downwards again (or once more) to slack the hoisting cable 20 while leaving the rope-threading block 4 in its fixed position. Then, the free end 21 of the hoisting cable 20 is unhooked from the rope-threading block 4, and the hoisting cable 20 is then passed under the rope-threading pulley 41 and exits from the rope-threading block 4. Finally, the free end 62 of the traction cable 60 is attached to the free end 21 of the hoisting cable 20.

[0185] exist Figure 13 In the sixth step (d6) shown, the traction cable 60 is pulled, which in turn pulls the free end 21 of the lifting cable 20. Therefore, the lifting cable 20 extends along the opposite path of the auxiliary path, such that it passes over the auxiliary pulley 35, where the free end 21 of the lifting cable is positioned in front of the auxiliary pulley 64. Simultaneously with the traction cable 60 pulling the free end 21 of the lifting cable 20, the hoisting winch is operated downwards in parallel to release the lifting cable 20, and this movement is thus accompanied by the operation.

[0186] exist Figure 14 In the seventh step (d7) shown, the auxiliary cable 60 is detached from the lifting cable 20, and then the free end 21 of the lifting cable 20 is hooked onto the rope block 4 to be in a three-strand configuration.

[0187] exist Figure 14 In the eighth step (d8) shown, the lifting winch is operated upward to raise the rope block 4 to a high position, which causes at least one sling 51 to slack.

[0188] exist Figure 14 In the ninth step (d9) shown, at least one sling 51 is detached from and removed from the rope block 4, and thus the lifting cable 20 is in its three-strand configuration, wherein the rope block 4 is suspended by the three-strand lifting cable 20.

[0189] Figures 15 to 17 A method for changing the rope threading from a two-strand configuration to a three-strand configuration is shown, and the method implements the following steps (e1) to (e9).

[0190] exist Figure 15 In the first step (e1) shown, the lifting cable 20 is in its two-strand configuration, wherein the rope block 4 is suspended by the two strands of the lifting cable 20; the free end 21 of the lifting cable 20 is fastened to the anchor point 15, and the rope block 4 is positioned at a given high position, positioned high and close to the boom end 11.

[0191] exist Figure 15 In the second step (e2) shown, at least one sling 51 is secured between the rope block 4 and the boom end 11, with the rope block 4 positioned high such that at least one sling 51 is slack at that high position.

[0192] exist Figure 15 In the third step (e3) shown, the hoisting winch is operated downwards until at least one sling 51 is tensioned and the rope block 4 is supported in a fixed position.

[0193] exist Figure 16 In the fourth step (e4) shown, the traction cable 60 is arranged to extend along the auxiliary path, first passing over the auxiliary pulley 63, then under the auxiliary pulley 64, and then over the secondary pulley 35.

[0194] exist Figure 16 In the fifth step (e5) shown, the free end 21 of the lifting cable 20 is detached from the anchor point 15, and then the free end 62 of the traction cable 60 is attached to the free end 21 of the lifting cable 20.

[0195] exist Figure 16In the sixth step (e6) shown, the traction cable 60 is pulled, which in turn pulls the free end 21 of the lifting cable 20. Thus, the lifting cable 20 extends along the opposite path of the auxiliary path, such that it passes over the auxiliary pulley 35, where the free end 21 of the lifting cable is positioned in front of the auxiliary pulley 64. Simultaneously with the traction cable 60 pulling the free end 21 of the lifting cable 20, the hoisting winch is operated downwards in parallel to release the lifting cable 20, and this movement is thus accompanied by the operation.

[0196] exist Figure 17 In the seventh step (e7) shown, the auxiliary cable 60 is detached from the lifting cable 20, and then the free end 21 of the lifting cable 20 is hooked onto the rope block 4 to be in a three-strand configuration.

[0197] exist Figure 17 In the eighth step (e8) shown, the lifting winch is operated upward to raise the rope block 4 to a high position, which causes at least one sling 51 to slack.

[0198] exist Figure 17 In the ninth step (e9) shown, at least one sling 51 is detached from and removed from the rope block 4, and thus the lifting cable 20 is in its three-strand configuration, wherein the rope block 4 is suspended by the three-strand lifting cable 20.

[0199] Generally, in order to perform the opposite configuration changes, it is sufficient to perform these steps in reverse order.

[0200] A method for changing the rope configuration from two strands to a single strand can be found by referring to... Figures 9 to 11 This is to describe it, but this time it should be read in reverse order (for this reading, the arrows indicating the movement of the cable should be ignored).

[0201] exist Figure 11 In the first step (c8) shown, the lifting cable 20 is in its two-strand configuration, wherein the rope block 4 is suspended by the two strands of the lifting cable 20; the free end 21 of the lifting cable 20 is fastened to the anchor point 15, and the rope block 4 is positioned at a given high position, positioned high and close to the boom end 11.

[0202] exist Figure 11 In the second step (c7) shown, at least one sling 51 is secured between the rope block 4 and the boom end 11, with the rope block 4 positioned high such that at least one sling 51 is slack at that high position.

[0203] exist Figure 11 In the third step (c6) shown, the hoisting winch is operated downwards until at least one sling 51 is tensioned and the rope block 4 is supported in a fixed position.

[0204] exist Figure 10 In the fourth step (c5) shown, the free end 62 of the traction cable 60 is attached to the free end 21 of the lifting cable 20; as previously described, the traction cable 60 passes over the auxiliary pulley 63.

[0205] exist Figure 10 In the fifth step (c4) shown, the free end 21 of the lifting cable 20 is detached from the anchor point 15, and then the free end 62 of the traction cable 60 is attached to the free end 21 of the lifting cable 20; thus, the traction cable 60 holds the lifting cable 20.

[0206] exist Figure 10 In the sixth step (c3) shown, the hoisting winch is operated upward to pull the hoisting cable 20 (and the traction cable 60) so that the hoisting cable 20 is no longer wrapped around the rope threading pulley 41, and then the free end 21 of the hoisting cable 20 is secured to the rope threading block 4 according to the single strand configuration, and the free end 62 of the traction cable 60 is unhooked from the hoisting cable 20.

[0207] exist Figure 9 In the seventh step (c2) shown, the lifting winch is operated upward to raise the rope block 4 to a high position, which causes at least one sling 51 to slack.

[0208] exist Figure 9 In the eighth step (c1) shown, at least one sling 51 is detached from and removed from the rope block 4, and thus the lifting cable 20 is in its single-strand configuration, wherein the rope block 4 is suspended by the single-strand lifting cable 20.

[0209] A method for changing the string configuration from three strands to a single strand can be found by referring to... Figures 12 to 14 This is to describe it, but this time it should be read in reverse order (for this reading, the arrows indicating the movement of the cable should be ignored).

[0210] exist Figure 14 In the first step (d9) shown, the lifting cable 20 is in its three-strand configuration, wherein the rope block 4 is suspended by the three-strand lifting cable 20; the free end 21 of the lifting cable 20 is fastened to the rope block 4, which is positioned at a given high position, positioned high and close to the boom end 11.

[0211] exist Figure 14 In the second step (d8) shown, at least one sling 51 is secured between the rope block 4 and the boom end 11, with the rope block 4 positioned high such that at least one sling 51 is slack at that high position.

[0212] exist Figure 14In the third step (d7) shown, the hoisting winch is operated downwards until at least one sling 51 is tensioned and the rope block 4 is supported in a fixed position. The traction cable 60 is arranged to extend along the auxiliary path, first passing over the auxiliary pulley 63 and then over the rear of the auxiliary pulley 64.

[0213] exist Figure 13 In the fourth step (d6) shown, the free end 62 of the traction cable 60 is attached to the free end 21 of the lifting cable 20, and the free end 21 of the lifting cable 20 is unhooked from the rope block 4.

[0214] exist Figure 13 In the fifth step (d5) shown, the hoisting winch is operated upward to pull the hoisting cable 20 (and the traction cable 60) so that the hoisting cable 20 is no longer wrapped around the auxiliary pulley 35; the traction cable 60 guides and holds the hoisting cable 20.

[0215] exist Figure 13 In the sixth step (d4) shown, the hoisting winch is operated upward to further pull the hoisting cable 20 (and the traction cable 60) so that the hoisting cable 20 is no longer wrapped around the rope pulley 41, and then the free end 21 of the hoisting cable 20 is secured to the rope block 4 according to the single strand configuration, and the free end 62 of the traction cable 60 is unhooked from the hoisting cable 20.

[0216] exist Figure 12 In the seventh step (d3) shown, the traction cable 60 can be removed (but it can also be left in place as a spare).

[0217] exist Figure 12 In the eighth step (d2) shown, the lifting winch is operated upward to raise the rope block 4 to a high position, which causes at least one sling 51 to slack.

[0218] exist Figure 12 In the ninth step (d1) shown, at least one sling 51 is detached from and removed from the rope block 4, and thus the lifting cable 20 is in its single-strand configuration, wherein the rope block 4 is suspended by the single-strand lifting cable 20.

[0219] A method for changing the rope configuration from three strands to two strands can be found by referring to... Figures 15 to 17 This is to describe it, but this time it should be read in reverse order (for this reading, the arrows indicating the movement of the cable should be ignored).

[0220] exist Figure 17In the first step (e9) shown, the lifting cable 20 is in its three-strand configuration, wherein the rope block 4 is suspended by the three-strand lifting cable 20; the free end 21 of the lifting cable 20 is fastened to the rope block 4, which is positioned at a given high position, positioned high and close to the boom end 11.

[0221] exist Figure 17 In the second step (e8) shown, at least one sling 51 is secured between the rope block 4 and the boom end 11, with the rope block 4 positioned high such that at least one sling 51 is slack at that high position.

[0222] exist Figure 17 In the third step (e7) shown, the hoisting winch is operated downwards until at least one sling 51 is tensioned and the rope block 4 is supported in a fixed position. The traction cable 60 is arranged to extend along the auxiliary path, first passing over the auxiliary pulley 63, then under and behind the auxiliary pulley 64.

[0223] exist Figure 16 In the fourth step (e6) shown, the free end 62 of the traction cable 60 is attached to the free end 21 of the lifting cable 20, and the free end 21 of the lifting cable 20 is unhooked from the rope block 4.

[0224] exist Figure 16 In the fifth step (e5) shown, the hoisting winch is operated upward to pull the hoisting cable 20 (and the traction cable 60) so that the hoisting cable 20 is no longer wrapped around the auxiliary pulley 35; the traction cable 60 guides and holds the hoisting cable 20.

[0225] exist Figure 16 In the sixth step (e4) shown, the hoisting winch is operated downward to provide slack, and then the free end 21 of the hoisting cable 20 is secured to the anchor point 15 according to the two-strand configuration, and the free end 62 of the traction cable 60 is unhooked from the hoisting cable 20.

[0226] exist Figure 15 In the seventh step (e3) shown, the traction cable 60 can be removed (but it can also be left in place as a spare).

[0227] exist Figure 15 In the eighth step (e2) shown, the lifting winch is operated upward to raise the rope block 4 to a high position, which causes at least one sling 51 to slack.

[0228] exist Figure 15In the ninth step (e1) shown, at least one sling 51 is detached from and removed from the rope block 4, and thus the lifting cable 20 is in its single-strand configuration, wherein the rope block 4 is suspended by the single-strand lifting cable 20.

Claims

1. A tilting boom crane (1), comprising: - A hoisting winch (2) is connected to a hoisting cable (20) having a free end (21). The hoisting winch (2) is operable upward to raise the free end (21) of the hoisting cable (20) and downward to lower the free end (21) of the hoisting cable (20). - A boom (10) is provided with a boom end (11), a main pulley (32) and a secondary pulley (35) are installed on the boom end, and the lifting cable (20) passes around the main pulley; - A rope block (4) having a hook member (40) for hooking a load, wherein the rope block (4) is held by the lifting cable (20) and includes a rope pulley (41) under which the lifting cable (20) can pass; The tilting boom crane (1) includes a set of devices for performing rope changes of the lifting cable (20) between three rope-threading configurations, the three rope-threading configurations being: - Single-strand configuration, in which the free end (21) of the lifting cable (20) is fastened to the rope block (4) at the outlet of the main pulley (32), such that the rope block (4) is suspended by a single strand of the lifting cable (20); - Two-strand configuration, in which the lifting cable (20) passes under the rope pulley (41) at the outlet of the main pulley (32), and the free end of the lifting cable is fastened to the anchor point (15) provided on the boom end (11), so that the rope block (4) is suspended by the two-strand lifting cable (20). - Three-strand configuration, in which, at the outlet of the main pulley (32), the lifting cable (20) passes under the rope-threading pulley (41), then rises to pass over the auxiliary pulley (35), and finally the free end (21) of the lifting cable is secured to the rope-threading block (4), such that the rope-threading block (4) is suspended by the three-strand lifting cable (20); The set of devices includes at least: - Support members (50; 51) for supporting the rope block (4) in a fixed position so that the hoisting winch (2) can be operated downward to slack the hoisting cable (20) while keeping the rope block (4) in its fixed position; - An auxiliary traction system (6), which is at least partially mounted on the pitch boom (10) and is configured to pull the free end (21) of the lifting cable (20).

2. The tilting boom crane (1) according to claim 1, wherein, The support members (50; 51) are selected from: - Ground support (50), on which the rope block (4) can rest; and - At least one sling (51) having a given length, and the at least one sling being able to be fastened to the boom end (11) and the rope block (4) so ​​as to suspend the rope block (4) below the boom end (11).

3. The tilting boom crane (1) according to claim 1 or 2, wherein, The auxiliary traction system (6) includes an auxiliary cable (60) of a given length, and the auxiliary cable is capable of being fastened to the free end (21) of the lifting cable (20) so that the free end (21) of the lifting cable (20) can be pulled by the auxiliary cable (60).

4. The tilting boom crane (1) according to claim 3, wherein, The auxiliary traction system (6) includes at least one auxiliary pulley (63) mounted on the end of the boom (11), and the auxiliary cable (60) passes over the at least one auxiliary pulley.

5. The tilting boom crane (1) according to claim 3 or 4, wherein, The auxiliary traction system (6) includes a traction actuator (61) connected to the auxiliary cable (60), such as, for example, a winch.

6. The pitching boom crane (1) according to any one of claims 3 to 5, comprising at least one auxiliary pulley (64) mounted on the boom end (11) and positioned below and behind the main pulley (32).

7. The tilting boom crane (1) according to any one of the preceding claims, wherein, The set of devices includes an anchoring member (52) adapted to be fastened to the lifting cable (20) and at least one flexible connector (53) that enables the anchoring member (52) to be connected to the rope block (4) or the free end (21) of the lifting cable (20) to be connected to the rope block (4) or to the anchoring member (52).

8. A rope threading method for performing rope threading changes of the lifting cable (20) of a pitch boom crane (1) according to any one of the preceding claims, wherein, The method of threading the rope includes at least the following: - The rope block (4) is supported in a fixed position by the support members (50; 51) so that the hoisting winch (2) can be operated downward to slack the hoisting cable (20) while keeping the rope block (4) in its fixed position. - By means of the auxiliary traction system (6), the free end (21) of the lifting cable (20) is pulled, or the lifting winch (2) is operated upward, so as to change the configuration of the lifting cable (20).

9. The threading method according to claim 8, for a threading change from the single-strand configuration to a final configuration of two-strand or three-strand configuration, includes at least the following steps: - The rope block (4) is supported by the support members (50; 51), and the hoisting winch (2) is operated downward to slack the hoisting cable (20) while leaving the rope block (4) in its fixed position. - Disconnect the free end (21) of the lifting cable (20) from the rope-threading block (4), and then pass the lifting cable (20) under the rope-threading pulley (41); - An auxiliary cable (60) of a given length is secured to the free end (21) of the lifting cable (20), the auxiliary cable (60) being integrated into the auxiliary traction system (6); and - By means of the auxiliary traction system (6), the free end (21) of the lifting cable (20) is pulled by the auxiliary cable (60), and then the free end (21) of the lifting cable (20) is tightened according to the final configuration. - Disconnect the auxiliary cable (60) from the free end (21) of the lifting cable (20).

10. The rope threading method according to claim 9, wherein, After the rope-threading block (4) is lowered to the ground support (50), the rope-threading block (4) is supported by the support, which is the ground support (50), and the rope-threading method includes: - After the lifting cable (20) is passed under the rope pulley (41) and before the auxiliary cable (60) is tightened, the anchoring member (52) is fastened to the lifting cable (20) and at least one flexible connector (53) is arranged, the at least one flexible connector connecting the anchoring member (52) to the rope block (4) or the at least one flexible connector connecting the free end (21) of the lifting cable (20) to the rope block (4) or to the anchoring member (52), and then the lifting winch (2) is operated upward to raise the rope block (4), the anchoring member (52) being configured to hold the rope block (4) by the lifting cable (20); - Once in the final configuration, the anchoring member (52) is removed from the lifting cable (20).

11. The rope-threading method according to claim 10, wherein, When the anchoring member (52) is fastened to the lifting cable (20): - Secure the anchoring member (52) to the descending section of the lifting cable (20) located between the main pulley (32) and the threading pulley (41), arrange the flexible connector (53) to connect the anchoring member (52) to the threading block (4), and secure the free end (21) of the lifting cable (20) to the descending section of the lifting cable (20) or to the anchoring member (52), and then suspend the threading block (4) from the anchoring member (52) via the flexible connector (53) during the raising of the threading block (4); - Alternatively, the anchoring member (52) may be fastened to the terminal section of the lifting cable (20) located between the rope block (41) and the free end of the lifting cable, the anchoring member (52) abutting against the rope block (4) during the raising of the rope block (4), and the flexible connector (53) may be arranged to connect the free end (21) of the lifting cable (20) to the rope block (4) or to the anchoring member (52).

12. The rope threading method according to claim 9, wherein, The rope block (4) is supported by the support member, which includes at least one sling (51) fastened to the boom end (11) and the rope block (4), such that the rope block (4) is suspended below the boom end (11).

13. The rope-threading method according to claim 12, wherein, The rope block (4) is supported by the at least one sling (51) by performing the following operations from the single strand configuration: - Operate the hoisting winch (2) upward to the given high position; - Secure the at least one sling (51) between the rope block (4) and the boom end (11), the high position being such that the at least one sling (51) is slack at that high position; - Operate the hoisting winch (2) downwards, at least until the at least one sling (51) is tensioned and supports the rope block (4).

14. The method of threading a rope according to any one of claims 9 to 13, wherein, The final configuration is a two-strand configuration, and in this case, the auxiliary cable (60) is directly fastened to the free end (21) of the lifting cable (20), such that the free end (21) of the lifting cable (20) is directly pulled by the auxiliary cable (60) towards the anchor point (15) to be fastened to the anchor point, so as to be in a two-strand configuration.

15. The method of threading a rope according to any one of claims 9 to 13, wherein, The final configuration is a three-strand configuration, and in this case, the auxiliary cable (60) extends along the auxiliary path, passes under the auxiliary pulley (64) mounted on the boom end (11), and then passes over the secondary pulley (35) so as to be finally hooked onto the free end (21) of the lifting cable (20); and the free end (21) of the lifting cable (20) is pulled by the auxiliary cable (60), and thus the free end of the lifting cable passes over the secondary pulley (35) so as to be finally secured to the rope block (4) in a three-strand configuration.

16. The threading method according to any one of claims 8 to 15, for a threading change from an initial configuration to the single-strand configuration, wherein the initial configuration is the two-strand configuration or the three-strand configuration, comprises at least the following steps: - The rope block (4) is supported by the support members (50; 51), and the hoisting winch (2) is operated downward to slack the hoisting cable (20) while leaving the rope block (4) in its fixed position. - According to the initial configuration, the free end (21) of the lifting cable (20) is unhooked; - Operate the hoisting winch (2) upward to wind the hoisting cable (20) so that the hoisting cable no longer passes under the rope pulley (41); - According to the single-strand configuration, the free end (21) of the lifting cable (20) is fastened to the rope-threading block (4).

17. The rope-threading method according to claim 16, wherein, The rope block (4) is supported by the support member, which includes at least one sling (51) fastened to the boom end (11) and the rope block (4), such that the rope block (4) is suspended below the boom end (11).

18. The rope-threading method according to claim 17, wherein, The rope block (4) is supported by the at least one sling (51) by performing the following operations from the initial configuration: - Operate the hoisting winch (2) upward to the given high position; - Secure the at least one sling (51) between the rope block (4) and the boom end (11), the high position being such that the at least one sling (51) is slack at that high position; - Operate the hoisting winch (2) downwards, at least until the at least one sling (51) is tensioned and supports the rope block (4).

19. The method of threading a rope according to any one of claims 16 to 18, wherein: - Before unhooking the free end (21) of the lifting cable (20) according to the initial configuration, the free end (21) of the lifting cable (20) is fastened to the auxiliary cable (60), which is integrated into the auxiliary traction system (6); - When the hoisting winch (2) is operated upward to wind the hoisting cable (20), the auxiliary traction system (6) releases the auxiliary cable (60) to follow the hoisting cable (20). - Once in the single-strand configuration, the auxiliary cable (60) is detached from the free end (21) of the lifting cable (20).

20. The threading method according to any one of claims 8 to 19, for a threading change from the two-strand configuration to the three-strand configuration, includes at least the following steps: - The hoisting winch (2) is supported by the support member, which includes at least one sling (51) fastened to the boom end (11) and the rope block (4) such that the rope block (4) is suspended below the boom end (11); - The hoisting winch (2) is operated downward to slack the hoisting cable (20) while leaving the rope block (4) in its fixed position; - Disconnect the free end (21) of the lifting cable (20) from the anchor point (15); - An auxiliary cable (60) of a given length is secured to the free end (21) of the lifting cable (20), the auxiliary cable (60) being integrated into the auxiliary traction system (6) and extending along the auxiliary path, the auxiliary cable passing under an auxiliary pulley (64) mounted on the boom end (11), and then passing over the secondary pulley (35) so as to finally hook onto the free end (21) of the lifting cable (20); as well as - By means of the auxiliary traction system (6), the free end (21) of the lifting cable (20) is pulled by the auxiliary cable (60) to pass over the secondary pulley (35) and finally secure to the rope block (4) in a three-strand configuration; - Disconnect the auxiliary cable (60) from the free end (21) of the lifting cable (20).

21. The threading method according to any one of claims 8 to 20, for a threading change from the three-strand configuration to the two-strand configuration, includes at least the following steps: - The rope block (4) is supported by the support member, which includes at least one sling (51) fastened to the boom end (11) and the rope block (4), such that the rope block (4) is suspended below the boom end (11); - The hoisting winch (2) is operated downward to slack the hoisting cable (20) while leaving the rope block (4) in its fixed position; - Disconnect the free end (21) of the lifting cable (20) from the rope-threading block (4); - An auxiliary cable (60) of a given length is secured to the free end (21) of the lifting cable (20), the auxiliary cable (60) being integrated into the auxiliary traction system (6) and passing under an auxiliary pulley (64) mounted on the end of the boom (11); - Operate the hoisting winch (2) upward to wind the hoisting cable (20) so that the hoisting cable no longer passes over the auxiliary pulley (35) and the auxiliary cable (60) passes over the main pulley (32) to keep the free end (21) of the hoisting cable (20). - Secure the free end (21) of the lifting cable (20) to the anchor point (15) provided on the end of the boom (11) to be in the two-strand configuration; - Disconnect the auxiliary cable (60) from the free end (21) of the lifting cable (20).

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