EP0409748B1 - Motorized device for rotating loads, with self-supply of energy, for cable-hoisting gears - Google Patents

Abstract

The device comprises a pulley block body (11) having several lines (25, 26, 27, 28) and several pulleys (12, 13) over which passes a lifting cable (4) forming a block and tackle (15), a grappling element (15) mounted to turn around a vertical shaft (14) and accommodating a hook (9), and electric motorization (16) to drive grappling element (15) in rotation. Pulley (13), over which the cable in the block and tackle passes, serves to drive an electric generator (35) which charges accumulators (36), the latter supplying the electricity needed for motorization (16). The device is applicable to turret slewing cranes and other cable lifting mechanisms.

Description

The present invention relates to a motorized load rotation device, self-supplied with energy, intended for cable lifting devices such as tower cranes, mobile cranes, overhead cranes, gantries, etc., this device ensuring the angular positioning. loads handled by such lifting devices.

It is well known, for these devices, to use rod hooks mounted to rotate on mittens with several strands by means of swivels, that is to say ball bearings.

In the most common embodiments, the rotation of the hook with or without suspended load is carried out manually when approaching the place of gripping or depositing the load. Despite the protective devices and safety measures provided, this type of operation always presents a bodily risk to the operator, whether by putting his hands on the moving parts or simply by being nearby of the load handled.

In more elaborate known embodiments (see for example French patent 1 229 282), the rotation of the hook or more generally of the load gripper is electrically motorized, and is controlled remotely from the driving position located on the lifting device . In the case of tower cranes with distributing jib, for example, distribution carriage spout and lifting cable forming a hauling system, there are already mittens with a remote-controlled gear motor for the rotary drive of the rotary hook. The electric power supply and remote control cable for the motorization of the revolving hook passes here on a reel, arranged on the load distribution carriage, and it is wound and unwound from the drum of the reel according to the position of the carriage on the boom and the height under the hook. In these embodiments, two difficulties are to be overcome, namely on the one hand, the maintenance of a sufficient mechanical tension on the power supply and remote control cable and on the other hand protection against the risk of shearing and deterioration of the power cable and remote control if the lifting cables twist.

As the German patent application published 3 234 395 teaches, the problems linked to the power and remote control cable can be solved by supplying the electric motor for driving the hook in rotation with a battery on board the muffle body, and by carrying out the remote control by radio control. This known solution however requires frequent recharging of the battery, in particular every night.

• Son autonomie, liée à la capacité de l'accumulateur hydraulique, est limitée.
• Sa masse totale est importante, si l'on considère l'ensemble des moyens mécaniques et hydrauliques nécessaires, et elle vient en déduction de la charge utile de l'engin de levage.
• Les moyens hydrauliques d'entraînement en rotation de la charge doivent être nécessairement commandés et contrôlés électriquement.
• Une source d'énergie distincte, de type électrique, est aussi nécessaire pour le récepteur des signaux de télécommande.

Finally, to avoid recharging the battery, a motorized load rotation device has already been imagined which is "self-supplied" with energy, that is to say that the motorized load rotation device itself ensures the production, storage, restitution and renewal of the energy necessary for its operation, by taking advantage of the running of the lifted lifting cable relative to a pulley of the device, this during the handling of the loads and in particular during the movements of up and down. Thus, it has been proposed, in the published Dutch patent application 7614360, corresponding to the preamble of claim 1, a mechanical transmission of at least one pulley to a hydraulic pump, and a hydraulic circuit with an accumulator which makes it possible to supply a hydraulic motor for driving the load in rotation. Such a hydraulic embodiment is expensive, and is only justified for the application to lifting devices handling very heavy loads, as is the case in particular of container port cranes. This device also has other drawbacks:

• Its autonomy, linked to the capacity of the hydraulic accumulator, is limited.
• Its total mass is significant, if we consider all the mechanical and hydraulic means necessary, and it is deducted from the payload of the lifting machine.
• The hydraulic means for driving the load in rotation must necessarily be electrically controlled and controlled.
• A separate electrical source is also required for the receiver of the remote control signals.

The present invention overcomes these drawbacks by providing a motorized load rotation device for cable hoists, self-supplied with electrical energy so that the electrical energy supplied ensures both the supply of the motorization d drive in rotation of the load and that of the means for receiving the remote control signals, the proposed device having a large autonomy for a relatively limited mass.

To this end, the device according to the invention comprises, in a known manner, a muffle body with several strands and with several pulleys over which at least one lifting cable passes forming a hauling, a hanger mounted rotatably about a substantially vertical axis linked to the muffle body and intended to receive a hook or other gripper for a load to be handled, a motorization for the rotary drive of the hanger around the aforementioned axis, a rotary energy generator driven from at least a pulley of the muffle body over which the lifting cable passes, and energy storage means, loaded from the generator and capable of supplying the energy necessary for supplying the motorization of the rotary drive of the hanger, the muffle body further comprising incorporated means for receiving control signals and for controlling the generator and the power supply of the motorization c he device is characterized in that the energy generator for supplying the motorization for driving the line in rotation is an electric current generator whose rotor is mechanically rotated from the pulley or pulleys muffle, in that the energy storage means are electrical energy storage means, in that the motorization for the rotary drive of the hanger is an electric motorization, and in that the same electrical energy storage means also supply the means for receiving the control signals and for controlling the electric current generator and the power supply of the electric motorization.

Thus, according to the invention, a motorized load rotation device is entirely autonomous and purely electric.

Although the device according to the invention essentially ensures the supply of electrical energy for the power supply of the motorization for rotating the hanger, and therefore for the load, it should be noted that this device also makes it possible to supply auxiliary functions such as automatic gripping of the load, search for center of gravity, etc. by eliminating any electrical supply cable leading to the muffle body.

According to a preferred embodiment of the invention, the electric current generator, carried by the muffle body, is an alternator with incorporated rectifier bridge and regulator, the rotor of which is driven in rotation from the pulley of the muffle body whose speed is the greatest, this alternator ensuring the charging of at least one accumulator constituting the means for storing electrical energy, while the motorization comprises a direct current electric motor which drives the suspension in rotation by means of a speed reducer, the supply of the electric motor from the accumulator (s) being controlled by an electrical and electronic control assembly incorporated in the muffle body.

Advantageously, the rotational drive of the alternator rotor, from the pulley of the muffle body whose speed is the greatest, is ensured by means of a speed multiplier preferably of the planetary type. This gives a minimum rotation, a rotation of the alternator at a high speed, optimal for the generation of electrical energy.

According to a particular embodiment, the direct current electric motor ensures the rotation of the hanger by means of a gear speed reducer comprising a first stage constituted by a planetary reducer, and a second stage constituted by a reducer with spur gear trains.

According to an additional characteristic, the device according to the invention is equipped with a relative position sensor, such as an absolute encoder or an incremental encoder, which controls the angular positioning of the rotary hanger relative to the muffle body, and a gyrometer which controls the absolute positioning of the rotating hanger. In the case of a relative position sensor constituted by a rotary encoder, this encoder can be driven in rotation by a pinion meshing with a toothed crown of the last set of spur gears belonging to the aforementioned reduction gear, this crown being wedged on the hanger rotating.

As for the revolving hanger itself, this comprises, according to another characteristic, on the one hand, a cylindrical upper part mounted on a ball bearing inside the muffle body and provided with an orifice provided for the passage of an electrical cable output from a collector, for the supply of stored electrical energy to the electrical functions of the gripper and / or other accessories, and on the other hand, a lower part external to the body of block and serving as support for the gripper. The power supply of any auxiliary functions, from the accumulator (s), is thus easily ensured.

• Figure 1 montre une grue à tour à flèche distributrice équipée du dispositif selon l'invention ;
• Figure 2 est une vue latérale d'ensemble du dispositif ;
• Figure 3 est une vue en plan par dessus du dispositif, correspondant à la vue latérale de la figure 2 ;
• Figure 4 est une vue schématique du dispositif avec ses organes internes ;
• Figure 5 représente le schéma synoptique de fonctionnement du dispositif.

In any case, the invention will be better understood with the aid of the description which follows, with reference to the appended diagrammatic drawing representing, by way of nonlimiting example, an embodiment of this motorized load rotation device, self-powered, for cable lifting devices:

• Figure 1 shows a tower jib crane equipped with the device according to the invention;
• Figure 2 is an overall side view of the device;
• Figure 3 is a plan view from above of the device, corresponding to the side view of Figure 2;
• Figure 4 is a schematic view of the device with its internal organs;
• Figure 5 shows the block diagram of the device.

As shown in Figure 1, the device according to the invention, generally designated by the reference 1, is intended to equip cable lifting devices, such as a tower crane 2 with distribution boom 3. The device 1 is suspended from the boom 3 by means of a lifting cable 4 forming a hauling 5 between the distribution carriage 6 and said device 1. At one end, the lifting cable 4 is fixed at a point 7 at the head of arrow 3; at the other end, the cable 4 is wound on the drum of a winch 8 arranged at the foot of the arrow 3. Under the device 1 is suspended a hook or rotating gripper 9 to which the load 10 to be handled is suspended or fixed .

With particular reference to FIGS. 2 and 3, the device 1 comprises in a known manner a block block 11 "four strands", with two pulleys 12, 13 arranged symmetrically with respect to a vertical axis 14, a hanger 15 mounted rotatably around of the vertical axis 14 intended to receive the hook or gripper 9 and an electric motorization 16 for the rotary drive of the hanger 15 around the axis 14, as indicated by an arrow F.

The muffle body 11 supports the horizontal axes of rotation 17,18 of the pulleys 12,13, which are protected by sheet metal housings 19,20 fixed on the lateral flanges 21,22 of said muffle body 11. The housings 19,20 have at their upper parts openings 23, 24 provided for letting pass respectively the two strands of cable 25, 26 leaving the pulley 12 and the two strands of cable 27, 28 leaving the other pulley 13.

As shown in FIG. 4, the motorization 16 consists of a direct current electric motor with permanent magnets 29 operating for example at a voltage of 24V, of a planetary speed reducer with a single gear train 30 just dimensioned for the torque to be transmitted in order to have the minimum inertia, and a speed reducer with straight drive trains 31 suitable for the rotary drive of the rotary hanger 15.

Furthermore, due to hauling 5, the pulley 13 disposed on the side of the driving strand 28 rotates twice as fast as the pulley 12 disposed on the side of the fixed strand 25. The hub 32 of the pulley 13 is wedged on the shaft d input 33 of a planetary speed multiplier 34 adapted to an alternator with built-in rectifier and regulator bridge 35 which charges one or more electric accumulators 36, housed in the muffle body 11.

The device also comprises a radio control transmitter-receiver 37 and an electrical and electronic control unit 38, incorporated into the muffle body 11. A rotating collector 39 allows the passage of electrical energy from the fixed part of the device 1 to the electrical functions of the part driven in rotation 9,10,15, in the case where such functions are provided. A relative position sensor 40, such as an absolute encoder or an incremental encoder, controls the relative angular positioning of the hanger 15 relative to the muffle body 11, and a gyrometer 41 controls the absolute positioning of the rotating hanger 15.

The revolving hanger 15 comprises a cylindrical upper part 42 mounted on a ball bearing 43 inside the block block 11 and provided with an orifice 44 for the passage of the electrical output cable from the collector 39 to the electrical functions of the gripper 9 or other specialized accessories, and a lower part 45 external to the muffle body 11 and serving to support the gripper 9.

The relative position sensor 40, such as an encoder, is driven in rotation by means of a pinion 46, meshing with a ring gear 47 belonging to the last set of spur gears 31 for driving the hanger 15 in rotation. , the crown 47 being wedged on the upper part 42 of the hanger 15.

The operation of the device 1 according to the invention, also illustrated by the block diagram of FIG. 5, is as follows:

During the lifting phases, during the raising or lowering of the muffle body 11, the pulley 13 whose speed is the greatest drives, via the planetary multiplier 34, the rotor of the alternator 35 which induces in the stator of this alternator a three-phase alternating electric current. The induced current is rectified by means of a diode rectifier bridge 48 and regulated by an incorporated regulator 49 which maintains for example at 24V the voltage of the current ensuring the recharging of the accumulator or accumulators 36.

The operation of the alternator 35 makes it possible to maintain the charge of the accumulator or accumulators 36 at a value sufficient to ensure the supply of energy to the on-board functions without recourse to external sources. In particular, the accumulator or accumulators 36 ensure, by means of the control assembly 38, the supply of the direct current electric motor with permanent magnets 29 at a voltage of 0 to 24V for the rotation drive of the hanger 15 and the gripper 9 with or without load, and the supply by the collector 39 of the electrical functions of the gripper 9 or other accessories.

The control signals are transmitted to the device 1 by wireless link between a fixed transceiver station 50 available to the operator and the on-board transceiver 37.

The control signals are processed at 51 as a function of the programmed or manual orders of the operator and of information coming from different sensors such as value of the load C, height H of the load and angular position P of the arrow 3 of the lifting device, etc ... which represent influential parameters for the rotation and the precise angular positioning of the load 10.

The transceiver on board 37 also receives the signals from the sensor 40 which gives the position of the rotating hanger 15 relative to the muffle body 11 and the signals from the gyrometer 41 which indicates the position of the rotating hanger 15 relative to the last position recorded at sensor 40.

The control signals are then amplified inside the electrical and electronic control assembly 38 to supply the motor 29 with an intensity and under a variable voltage as a function respectively of the desired torque and of the rotational speed.

This produces a motorized load rotation device which is self-supplied with energy, the relative movement of the lifting cable 4 and of the device 1 causing, via the alternator 35, the charge of the accumulator 36 which serves as a reserve of energy for supplying the motorization 16 of the rotary hanger 15. It is therefore understood that the lifting movements allow the device to produce and renew its energy, this during normal use of the lifting device. In this regard, it can also be noted that not only the up and down movements of the muffle body 11, but also the distribution movement by movement of the carriage 6 along the arrow 3, contribute to the generation of electrical energy: even if the movement of the distribution carriage 6 remains relatively slow, it may correspond to a movement of the lifting cable 4 in addition to that caused by the up / down movement and thus driving the alternator 35 at a higher speed.

• . en remplaçant l'alternateur 35 par un autre générateur de charge tel qu'une dynamo ;
• . en remplaçant l'accumulateur 36 par un autre appareil ou composant qui emmagasine l'énergie électrique produite ;
• . en modifiant des particularités constructives telles que la position du capteur de position relative 40 dans la chaîne cinématique d'entraînement en rotation de la suspente 15, ou encore les moyens d'entraînement de l'alternateur 35 à partir de la poulie 13 ;
• . en adaptant le dispositif selon l'invention à un corps de moufle ayant un nombre de brins et de poulies différent ;
• . en destinant ce dispositif à des appareils de levage à câble autres que les grues à tour à flèche distributrice.

Of course, the invention is not limited to the sole embodiment of this motorized load rotation device, self-supplied with energy, which has been described above, by way of example. In particular, we would not depart from the scope of the invention:

• . replacing the alternator 35 with another charge generator such as a dynamo;
• . by replacing the accumulator 36 with another device or component which stores the electrical energy produced;
• . by modifying constructive features such as the position of the relative position sensor 40 in the kinematic chain for driving the hanger 15 in rotation, or else the means for driving the alternator 35 from the pulley 13;
• . by adapting the device according to the invention to a muffle body having a different number of strands and pulleys;
• . by designating this device for cable lifting devices other than distribution jib tower cranes.

Claims (8)

1. Motorised load rotation device, with an autonomous power supply, for rope lifting mechanisms, comprising a pulley block body (11) with several falls (25, 26, 27, 28) and several pulleys (12, 13) over which at least one lifting rope (4) passes, forming a block and tackle (5), a suspension link (15) mounted so as to rotate about a substantially vertical axis (14) connected to the pulley block body (11) and designed to receive a hook or other holder (9) for a load (10) to be handled, motorisation (16) for driving the suspension link (15) in rotation (arrow F) about the aforesaid axis (14), a rotary power generator (35) driven from at least one pulley (13) on the said pulley block body (11) over which the lifting rope (4) passes, and power storage means (36), charged from the generator (35) and able to provide the power necessary for supplying the motorisation (16) driving the suspension link (15) in rotation, the pulley block body (11) also having means incorporated (37, 38) for receiving command signals and controlling the generator (35) and the motorisation (16) power supply, characterised in that the power generator for supplying the motorisation (16) for driving the suspension link in rotation is an electric current generator (35) whose rotor is driven in rotation mechanically from the pulley or pulleys (13) on the pulley block body (11), in that the power storage means are electrical power storage means (36), in that the motorisation for driving the suspension link (15) in rotation is an electric motorisation (16), and in that the same electrical power storage means (36) also supply the means (37, 38) for receiving the command signals and for controlling the electric current generator (35) and the power supply to the electric motorisation (16).
2. Motorised load rotation device according to Claim 1, characterised in that the electric current generator carried by the pulley block body (11) is an alternator (35) with rectifier bridge (48) and regulator (49) incorporated, whose rotor is driven in rotation from the pulley (13) on the pulley block body (11) with the greatest speed, this alternator (35) charging at least one accumulator (36) constituting the electrical power storage means.
3. Motorised load rotation device according to Claim 2, characterised in that the motorisation (16) comprises a DC electric motor (29), which drives the suspension link (15) in rotation through reduction gearing (30, 31), the power supply to the electric motor (29) from the accumulator or accumulators (36) being controlled by an electrical and electronic control unit (38) incorporated in the pulley block body (11).
4. Motorised load rotation device according to Claim 2 or 3, characterised in that the driving in rotation of the alternator rotor (35), from the pulley (13) on the pulley block body (11) with the greatest speed, is provided through a step-up gear (34), preferably of the sun and planet type.
5. Motorised load rotation device according to Claim 3, characterised in that the DC electric motor (29) drives the suspension link (15) in rotation through reduction gearing with gears comprising a first stage consisting of a planetary reduction gear (30) and a second stage consisting of reduction gearing with spur gear trains (31).
6. Motorised load rotation device according to any one of Claims 1 to 5, characterised in that it is equipped with a relative position sensor (40), such as an absolute coder or an incremental coder, which monitors the angular position of the rotating suspension link (15) with respect to the pulley block body (11), and a gyrometer (41) which monitors the absolute position of the rotating suspension link (15).
7. Motorised load rotation device according to both of Claims 5 and 6, characterised in that the relative position sensor, consisting of a rotary coder (40), is driven in rotation by a gear (46) meshing with an annular gear (47) on the last train of spur gears (31) belonging to the reduction gearing driving the suspension link (15) in rotation, this annular gear (47) being fastened to the rotating suspension link (15).
8. Motorised load rotation device according to any one of Claims 1 to 7, characterised in that the rotating suspension link (15) comprises, on the one hand, a top cylindrical part (42) mounted on a thrust ball bearing (43) inside the pulley block body (11) and provided with an orifice (44) for the passage of an electric output cable from a rotary collector (39), for carrying stored electrical power to the electrical functions of the holder (9) and/or other accessories, and on the other hand a bottom part (45) external to the pulley block body (11) and serving as a support for the holder (9).

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