BE1021044B1 - DEVICE AND METHOD FOR TURNING THE LIFTING CABLE OF A CRANE VIA ITS HOOK BY ROLLING THE CABLE ON THE CRANE LIFTING WINCH - Google Patents

Abstract

D ISPOSITIVE AND METHOD OF TENSIONING THE LIFTING CABLE OF A CRANE VIA THE HOOK BY WINDING THE CABLE ON THE CRANE LIFTING WINCH The invention relates to a device (14) and a method for tensioning the lifting cable. lifting (2) of a crane (1) via its hook (3). The device (14) comprises a pulley (8), a cable (7), a counterweight (11) and a winch (6), the pulley (8) being hookable to the hook (3), the cable (7) being fixable by its first end in a manner removable from the counterweight (11), being posable around the pulley (8) and being rollable on the winch (6) by its second end and the winch (6) being positioned fixed with respect to the counterweight (11). The method includes lifting the hook (3) via the pulley (8) tensioned using the cable (7) and the counterweight (11).

Description

DEVICE AND METHOD FOR TURNING THE LIFTING CABLE OF A CRANE VIA ITS HOOK BY ROLLING THE CABLE ON THE CRANE LIFTING WINCH

The present invention relates to a device and a method for tensioning the hoisting rope of a crane via its hook by winding the cable on the crane hoist winch.

Cranes are normally used to lift heavy loads. To this end, a crane includes a hoisting rope that can be wound on a hoist winch. One or more pulleys guide the hoisting rope. A hook is mounted at the free end of the cable to hook the loads to lift. The invention applies especially in the field of high capacity cranes and more specifically (but not exclusively) to cranes used to mount and dismount wind turbines. Similar cranes can be built either as mobile or crawler cranes and as telescopic or lattice boom.

Now that many wind turbines have been installed, more and more often the rotor, one or more blades and / or turbine of a wind turbine must be dismantled for repair and / or maintenance. This means that a truck must be lowered from heights of 80 to 140m.

A problem with disassembly of such a heavy weight is that a heavy load must be hooked to the hook - the hoisting rope being wound on the hoist winch - and must then be lowered. At the time of winding of the hoisting rope without a weight being caught, the cable nevertheless gets caught between the layers on the hoist winch drum. The descent of heavy loads is then dangerous because this creates important shakes. Such a descent is barely controllable. Non-uniform unwinding of the cable also causes much faster cable wear.

In the patent literature of different systems to put in tension a lifting cable are proposed. It is known to load the hook as proposed in EP 2 358 227 A1, but such a load is not sufficient at all to tension the lifting cable of a high capacity crane in order to be able to wind this cable in a uniform manner. . It is also known to develop a guide pulley in a way to better guide the cable towards the winch, but this is not enough at all to wind the cable of a high capacity crane in a uniform manner. Systems as proposed in JP 7-144887 or GB 1914 18 996 A1 can not be easily integrated into existing cranes and can not then be used in on-site cranes. The object of the invention is therefore to provide a device and method with which the lifting cable of a high capacity crane can be wound in a uniform manner so that such a heavy load can be lowered in a manner controlled.

According to the invention, this object is achieved with a device for tensioning the lifting cable of a crane via its hook by winding the cable on the crane hoist winch, comprising a help pulley, a first cable a counterweight and a first assist winch, the assist pulley being hook-able to the hook, the first assist cable having a first end and a second end, being fixable by its first end in a removable manner counterweight, being posable around the help pulley and being rollable on the first aid winch by its second end and the first aid winch being positioned fixed relative to the counterweight. Using such a device the help pulley can be hooked to the lowered hook (the hoisting rope being unwound), the help cable can be put around the pulley and fixed to the counterweight and after, the hook can be lifted (the hoisting rope is rewound). Thanks to the counterweight, a minimum tension can then be maintained on the hoisting rope and allows a good winding of the hoist rope on the hoist winch drum. The counterweight is chosen according to the required tension.

The pulley is preferably dimensioned so that it can remain hooked without interfering with the descent of heavy goods vehicles, such as, for example, the rotor, one or more blades and / or the turbine of a wind turbine.

Instead of a single pulley, it is also possible to use several pulleys to multiply the load on the hook when winding the hoisting rope.

A preferred embodiment of the device according to the invention comprises a second helper cable, having a smaller diameter than the first helper cable and a second helper winch, having a diameter smaller than the first hoist winch. aid, the second helper cable having a first end and a second end, being fixable by its first end to the first end of the first helper cable and being rollable on the second winch by its second end and the second winch being positioned fixed compared to the counterweight.

After lifting the hook with the pulley and the first helper cable around the pulley, this first cable must be retrieved before heavy loads can be lowered. The first cable can be lowered using the second help cable of this preferred device.

Even more preferred, such a device according to the invention further comprises a rope to more easily be able to descend the first helper cable.

Such a rope can be dropped without problems and without subsidiary means. Such ropes are currently already used to guide the rotor of a wind turbine assembly thereof. After mounting the rotor, these ropes are released without problems.

It would also be possible to choose the second cable in order to be able to release this cable in order to recover it without the help of an additional rope. Nevertheless, such a cable would still be too expensive.

A particular embodiment of such a device according to the invention comprises a winch to which the rope is rollable by one of these ends.

A preferred embodiment of a device according to the invention comprises a frame, being weighted with the counterweight. Such a chassis makes the device easily movable to easily place the device in place.

Preferably the first aid winch of such a device is mounted on the frame.

When such a device comprises a second help winch as described, this second help winch is preferably mounted on the frame.

In a device according to the invention with chassis, the first helper cable is preferably fixable by its first end in a manner removably to the frame in order to fix it to the counterweight.

According to the invention the objective is also achieved with a method for tensioning the lifting cable of a crane via its hook by winding the cable on the winch of lifting the crane, this method comprising: - ensuring that the hook descended; - Take a first aid cable, having a first end and a second end, being wound by its second end on a first aid winch, this winch being positioned fixed relative to a counterweight, put this cable around a assist pulley, this assist pulley being hooked to the hook and securing the first end of this cable to the counterweight in a removable manner; - lift the hook of the crane so that the first help cable unrolls the first help winch; - recover the first help cable.

When the assist pulley is not yet attached to the hook, this pulley is preferably first hooked to the hook before placing the first helper cable around this helper pulley.

In order to recover the first aid cable, its first end is preferably first disassembled from the counterweight and is attached to a first end of a second assist cable, this second assist cable having a diameter smaller than the first helper cable and being wound by its second end around a second helper winch, this second helper winch having a diameter smaller than the first helper winch and being fixedly positioned relative to the counterweight, then the first helper cable is wound on the first helper winch via the helper pulley, so that the second helper cable unwinds from the second helper winch and then the second helper cable is retrieved.

In order to recover the second help cable, its first end is preferably first removed from the first aid cable and is attached to a first end of a rope, this rope being wound by its second end, then the second helper cable is wound on the second help winch via the help pulley, so that the rope unwinds and then the rope is retrieved.

In a preferred method according to the invention, a device according to the invention is used.

The present invention will now be explained in more detail by describing preferred devices and methods according to the invention. The purpose of this description is solely to provide an illustrative example of the invention and to disclose other advantages and details of the devices and methods according to the invention, and it should in no way be construed as a limitation of the scope of the invention. use of the invention or the patent rights claimed in the claims.

In this detailed description, the numerical references refer to the accompanying drawings, in which: - Figure 1 is a side view of a crane and a device according to the invention, the hook of the crane being lowered and coupled to device; - Figure 2 is a side view of the crane and the device of Figure 1, with the hook raised; FIG. 3 is a side view of the crane and the device of FIG. 1, with the hook raised and the first helper cable being wound up; FIG. 4 is a side view of the crane and the device of FIG. 1, with the hook raised and the second helper cable being wound up; - Figure 5 is a detail of Figure 1 in which the device is shown more detailed; - Figure 6 is a detail of Figure 2 at the frame of the device; - Figure 7 is a detail of Figure 3 at the frame of the device; - Figure 8 is a detail of Figure 4 at the frame of the device.

In Figures 1 to 4, a device according to the invention is shown in use with a crane (1) high voltage developed lattice boom. This crane (1) is used to lift heavy loads. To this end, this crane (1) comprises a lifting cable (2) which can be wound on a hoist (4). Several pulleys (13) guide the hoisting rope (4). A hook (3) is mounted at the free end of the hoisting rope (2) to hook the loads to be lifted.

The device (14) according to the invention as illustrated is designed to tension the lifting cable (2) of the crane (1) via its hook (3) by winding the cable (2) on the hoist winch (4). ) of the crane (1).

This device (14) comprises a frame (5). On this frame (5) a first help winch (6) and a second help winch (9) are mounted. Between these help winches (6, 9), the frame is ballasted with the counterweight (11). The device (14) also includes a first assist cable (7), a second assist cable (10) and a cord (12). The drum of the second assist winch (9) is smaller in diameter than the drum of the first assist winch (6) and the second assist wire (10) is smaller in diameter than the first assist wire. (7). The first helper cable (7) is rollable on the first helper winch (6) and the second helper cable (10) is rollable on the second helper winch (9). In addition, the device comprises a help pulley (8), which can be hooked to the hook (3) of the crane (1) to pass the help cables (7, 10) and the rope (12).

To feed the winches (6, 9) fixed to the frame (5), the device (14) may for example comprise a motor and hydraulic pumps.

In Figures 1 and 5, the hook (3) of the crane (1) is lowered and the lifting cable (2) of the crane (1) is unwound from the hoist winch (4) of the crane (1). The help pulley (8) is hooked to the hook (3). The first support cable (7) is at its first end hooked to the frame (5), is placed on the help pulley (8) and is wound on the first help winch (6) by its second end. The second assist cable (10) is wound on the second assist winch (9). The rope (12) is not shown, but may for example be wound on a winch.

In Figures 2 and 6 the hook (3) is lifted by winding the hoisting rope (2) on the hoist winch (4). The first helper cable (7) runs from the drum of the first assist winch (6). As the first end of this first helper cable (7) is fixed on the frame (5), and as this frame (5) is ballasted with the counterweight (11), the lifting cable (4) remains in all the time. tension and rolls up uniformly on the hoist winch (4).

In order to recover the first assist cable (7) after the hook (3) is raised and the lifting cable (2) wound up, the first end of the first assist cable (7) is taken off the chassis (5) and is attached to the first end of the second assist cable (7). As shown in FIGS. 3 and 7, the first helper cable (7) is then rewound onto the first helper winch (6) by unwinding the second helper cable (10) from the second helper winch (9). The first help cable (7) is then recovered and can be unhooked from second help cable (10).

In order to recover the second help cable (10), a rope (12) is then attached to the first end of the second assist cable (10). As shown in FIGS. 4 and 8, the second assist cable (10) is then rewound onto the second assist winch (9) by unrolling the rope (12). The rope (12) may for example be unwound by hand, or with a winch. The second help cable (10) is then recovered and can be unhooked from the rope (12).

Then, we pull on the rope (12) to make it fall to the ground.

The pulley (8) remains attached to the hook (3).

Then, a heavy load can be hooked up to the hook (3) to lower it. The help pulley (8) is dimensioned so as not to hinder the attachment of such a load.

As indicative (and not limiting), it can be said that for a lifting height of the hook (3) between 80 and 140 m, the minimum tension on the hoisting rope (2) is preferably about 3T. To this end, counterweights (11) of 20T (in total) can be chosen to ballast the frame (5), taking into account that the first help winch (6) has a weight of about 3.6T .

Claims (13)

1. Device (14) for tensioning the lifting cable (2) of a crane (1) via its hook (3) by winding the cable (2) on the hoist winch (4) of the crane (1) ), characterized in that said device comprises a helper pulley (8), a first assist cable (7), a counterweight (11) and a first assist winch (6), the assist pulley ( 8) being hookable to the hook (3), the first assist cable (7) having a first end and a second end, being fixable by its first end in a detachable manner to the counterweight (11), being posable around the aid pulley (8) and being rollable on the first aid winch (6) by its second end and the first aid winch (6) being positioned fixed relative to the counterweight (11). 2. Device (14) according to claim 1, characterized in that this device comprises a second helper cable (10) having a diameter smaller than the first helper cable (7) and a second helper winch (9), having a diameter smaller than the first assist winch (6), the second assist cable (10) having a first end and a second end, being fixable by its first end to the first end of the first cable helper (7) and being rollable on the second helper winch (9) by its second end and the second helper winch (9) being positioned fixed relative to the counterweight (11). 3. Device (14) according to claim 2, characterized in that this device comprises a rope (12). 4. Device (14) according to claim 3, characterized in that this device comprises a winch to which the rope (12) is rollable by one of these ends. 5. Device (14) according to one of the preceding claims, characterized in that this device comprises a frame (5), being weighted counterweight (11). 6. Device (14) according to claim 5, characterized in that the first aid winch (6) is mounted on the frame (5). 7. Device (14) according to one of claims 2 to 4 and claim 5 or 6, characterized in that the second help winch (9) is mounted on the frame (5). 8. Device (14) according to one of the preceding claims, characterized in that the first helper cable (7) is fixable by its first end in a manner removably to the frame (5) to fix it to the counterweight ( 11). 9. Method for tensioning the lifting cable (2) of a crane (1) via its hook (3) by winding the cable (2) on the hoisting winch (4) of the crane (1), characterized in that the method comprises: - ensuring that the hook (3) is lowered; - Take a first helper cable (7), having a first end and a second end, being wound by its second end on a first aid winch (6), this winch (6) being positioned fixed relative to a counterweight (11), put this cable (7) around a help pulley (8), this help pulley (8) being hooked to the hook (3) and fix the first end of this cable (7) to counterweight (11) in a removable manner; - lift the hook (3) of the crane (1) so that the first helper cable (7) rolls out of the first help winch (6); - recover the first help cable (7). 10. Method according to claim 9, characterized in that the help pulley (8) is first hooked to the hook (3) before placing the first helper cable (7) around this help pulley ( 8). 11. Method according to claim 9 or 10, characterized in that in order to recover the first aid cable (7), its first end is first removed from the counterweight (11) and is fixed to a first end of a second aid cable (10), said second assist cable (10) having a smaller diameter than the first assist cable (7) and being wound by its second end around a second assist winch ( 9), this second assist winch (9) having a diameter smaller than the first aid winch and being fixedly positioned relative to the counterweight (11), then the first assist cable (7) is wound on the first assist winch (6) via the assist pulley (8), so that the second assist cable (10) is unwound from the second assist winch (9) and then the second assist cable (10). ) is recovered. 12. Method according to claim 11, characterized in that in order to recover the second aid cable (10), its first end is first removed from the first aid cable (7) and is fixed at a first end. a rope (12), this rope (12) being wound by its second end, then the second assist cable (10) is wound on the second assist winch (9) via the assist pulley (8) , so that the rope (12) unwinds and then the rope (12) is recovered. 13. Method according to one of claims 9 to 12, characterized in that a device (14) according to one of claims 1 to 8 is used.