EP2459477B1 - Mechanical assembly with traction sheave and rope, and lifting device of the chain hoist type equipped with such a mechanical assembly - Google Patents

Description

TECHNICAL AREA

The present invention relates to the field of handling equipment and relates more particularly to a mechanical assembly comprising a pulley and a rope provided with abutment members, and a hoist or traction device of the type chain hoist or cable comprising such a mechanical assembly.

STATE OF THE PRIOR ART

In many industrial processes, including assembly processes, it is necessary to vertically move large objects of high weight.

This is the case, for example, in the field of aeronautics where the assembly of an aircraft comprises a number of operations for lifting a load, for example, a high lift device (trailing edge flap , leading edge, bonnet ...) to mount it on one of the wings.

The lifting operations of such objects are generally carried out using a lifting device of the type chain hoist or cable.

The figure 1 illustrates an example of a chain hoist used to perform such operations.

The hoist 1 comprises a control device 10 and a lifting device 20, coupled to one another at a housing 2. The housing 2 is usually hooked to a hoist carrier 3 via A suspension hook 4. The carriage 3 can be moved along a monorail 5 or a bracket, to position the hoist 1 at a given location.

The control device 10 of the hoist comprises a control chain 11 which meshes with a control pulley located in the housing 2. The lifting device 20 comprises a lifting chain 21 to which a lifting hook 22 is attached. Lifting chain 21 meshes with a lifting pulley, itself located in the casing 2. Said chains 11, 21 may be link or roller chains, and are usually made of steel.

Said pulleys are mounted fixed in translation on the housing 2, and coupled to each other by means of a gear reduction gear. Said gear reducer multiplies the torque of the control pulley and transmits it to the hoisting pulley.

Furthermore, it is known that a cable hoist is distinguished from the chain hoist essentially by the lifting device. Indeed, the lifting device of a cable hoist generally comprises a lifting drum, on which is wound a hoisting rope. Also, the hoisting rope, usually made of steel, is attached to the drum at one end, while a hoisting hook is attached to the second end. The actuation of the cable hoist can be achieved by a chain control device identical to that described above. The drum is then coupled to the control pulley by a gear reducer, so as to be rotated by the control pulley.

It should be noted that this type of hoist differs from the muffle hoist, which comprises two mittens, one fixed and the other mobile, each having one or more pulleys on which passes a single rope. One end of the rope is attached to one of the mittens and a lifting hook is attached to the movable muffle. When a tensile force is applied to the rope, the movable muffle approaches the fixed muffle and thus lifts the load attached to the lifting hook.

However, chain or cable hoists, as described above, have the disadvantage that, when the control chain is actuated, it can oscillate and come to rub and / or hit the object to be lifted or a neighboring object, and therefore cause deterioration of said object.

• une poulie de commande comportant une pluralité d'alvéoles délimités chacun au mois partiellement par une surface formant butée, et
• des moyens de transmission comprenant des organes de butée prévus pour venir s'engrener dans lesdits alvéoles, de manière à ce que l'actionnement desdits moyens de transmission entraîne, par formation de butée des organes de butée engrenés dans les alvéoles contre les surfaces formant butée correspondantes, la rotation de ladite poulie de commande,

lesdits moyens de transmission comprenant une corde de commande en matériau synthétique munie desdits organes de butée.The document WO 2004/073576 A2 (British Columbia Institute of Technology) describes a mechanical assembly, comprising:

• a control pulley comprising a plurality of cells each partially delimited by a stop surface, and
• transmission means comprising stop members adapted to engage in said cells, so that the actuation of said transmission means causes, by abutment formation stop members geared in the cells against the abutment surfaces corresponding, the rotation of said control pulley,

said transmission means comprising a control rope of synthetic material provided with said stop members.

More generally, there are numerous mechanical assemblies comprising a control pulley and a control chain cooperating by meshing with said pulley to drive in rotation thereof. These mechanical assemblies are not necessarily suspended. However, the control chain is also likely to oscillate and come to strike and / or rub an object located near it.

Said object may therefore have particularly damaging degradations.

STATEMENT OF THE INVENTION

The main purpose of the invention is to present a mechanical assembly comprising a control pulley driven in rotation by a control rope, making it possible to reduce the risk of damage to an object located in the vicinity, because of contact with the rope control .

• une poulie de commande comportant une pluralité d'alvéoles délimités chacun au moins partiellement par une surface formant butée, et
• des moyens de transmission comprenant des organes de butée prévus pour venir s'engrener dans lesdits alvéoles, de manière à ce que l'actionnement desdits moyens de transmission entraîne, par formation de butée des organes de butée engrenés dans les alvéoles contre les surfaces formant butée correspondantes, la rotation de ladite poulie de commande.

To do this, the subject of the invention is a mechanical assembly according to all the technical characteristics, in combination, of claim 1. Said mechanical assembly comprising:

• a control pulley comprising a plurality of cells each delimited each at least partially by an abutment surface, and
• transmission means comprising stop members adapted to engage in said cells, so that the actuation of said transmission means causes, by abutment formation stop members geared in the cells against the abutment surfaces corresponding, the rotation of said control pulley.

According to the invention, the transmission means comprise a control rope of natural and / or synthetic material provided with said abutment members.

By cell is meant a space defined by a surface of the control pulley, whose abutment surface, in which can engage a stop member.

Preferably, said cells are located at the circumferential surface of the pulley of ordered. The circumferential surface of the pulley is the surface which delimits the outer periphery of the pulley.

Rope means a long body of circular or polygonal cross section, for example rectangular, square, trapezoidal, or having any number of sides.

Thus, whatever the use of the mechanical assembly, the control rope is likely to oscillate or to present a movement substantially orthogonal to its longitudinal axis, and thus to strike and / or rub an object located nearby.

However, unlike the examples of the prior art described above, said mechanical assembly according to the invention reduces the risk of degradation of said object due to contact with the control cord.

Indeed, because said control rope is made of a natural and / or synthetic material, it has a lower density and greater flexibility than steel chains commonly used in cooperation with a pulley, for example that used in the hoist of the example of the prior art described above.

Thus, when the control rope according to the invention hits said object, the kinetic energy acquired by the rope during its movement and transmitted to the object during the impact is substantially less than the energy present in the case of a steel chain. The object is then little, if any, damaged during such a shock.

In the same way, the risk of damage to said object, due to possible friction by the control cord, are also reduced or even eliminated. Indeed, because of the lower density and hardness of the control rope compared to those of the steel chain, and because of its greater flexibility, the contact force exerted by the rope against the object has an intensity substantially weaker. The harmful effects of a possible friction of the control cord on said object are therefore substantially reduced or even eliminated.

Thus, the risk of damage to an object to be lifted or a nearby object, when the control rope according to the invention comes to rub or hit said object, are substantially reduced.

Preferably, each cell is at least partially defined by two abutment surfaces. The abutment surfaces are substantially orthogonal to the circumferential axis of the control pulley.

The material of said control rope may be chosen from polyamides, polyesters, polypropylenes and polyolefins.

According to the invention, the control rope is formed of a son assembly. The threads, twisted or braided, can be assembled to form several strands. The rope is then formed of the assembly of the strands to each other.

Preferably, the yarns are made of polyamide. They can form several strands, preferably an even number, for example four. The rope can have a rest diameter of about 7 millimeters and a tension diameter of about 6 millimeters.

Advantageously, said stop members are arranged or formed along the control rope according to the invention, and can not be moved along it.

Advantageously, said abutment members are made of a material chosen from rubber and plastic. Thus, for the same reasons as those presented above, any risk of degradation of the object to be lifted or a neighboring object by contact with one of the abutment members is substantially reduced. Preferably, said abutment members are made of rigid PVC thermoplastic and have a minimum tensile strength of the order of 5 daN / mm ² .

Preferably, said stop members have an outer shape of a cylinder of revolution, whose axis of revolution coincides substantially with the longitudinal axis of the control cord. The stop members can be obtained by machining. The diameter of the abutment members may be of the order of 20 millimeters and have a length of the order of 20 millimeters.

According to the invention, each of said stop members is fixed to said control rope by fixing means, said fixing means extending through said control rope. Preferably, the fastening means extend along an axis substantially orthogonal to the longitudinal axis of the control rope. When the control rope has several strands, said fixing means may extend in a space made by a local spacing of two groups of strands each comprising the same number of strands.

Advantageously, said fixing means are located inside the outer contour of each stop member. By outer contour is meant the outer surface delimiting the abutment member. Thus, the fastening means can not come into contact with the object to be lifted or a neighboring object. Any risk of degradation is avoided.

According to the preferred embodiment, each of said abutment members is formed of two half-shells assembled to one another by said fixing means, said fastening means exerting a nip of said control rope between said half-shells . Said fastening means may then comprise a screw and a nut. The screw can then extend through the rope, preferably between two groups of strands forming the rope. The fastening means pinch said rope, indirectly through the two half-shells.

According to an alternative embodiment, each of said abutment members is formed in one piece, by injection molding. The fastening means may then be an insert disposed inside the stop member, so as to pass through the control rope.

Alternatively to the abutment members according to the invention described above, the abutment members may be nodes formed by said rope of ordered. The nodes may have, for example, the known shape of the half-node, the eight-node, or any other form making the nodes capable of meshing with said cells of the control pulley and cooperating with said abutment surfaces.

Preferably, said control pulley comprises a groove extending between said cavities at the circumferential surface of said pulley, said groove being intended to accommodate said control rope.

The invention also relates to a lifting apparatus for suspension, comprising a lifting device for lifting an object.

The hoist comprises a mechanical assembly according to any one of the preceding features, said control pulley being coupled to said hoisting device so that rotation of the control pulley causes actuation of the hoist.

Thus, for the same reasons as above, any risk of degradation of the object to be lifted or a nearby object due to shocks and friction with the lifting rope or associated stop members is discarded.

Said lifting device may comprise an assembly formed of a lifting pulley coupled to said control pulley and comprising a plurality of cavities, and a lifting rope of natural and / or synthetic material provided with abutment members intended to come mesh in said alveoli of the pulley of lifting. The lifting pulley, the lifting rope and the associated abutment members may have any of the features described above with reference to the control rope according to the invention and the associated abutment members. Thus, any risk of degradation of the object to be lifted or a nearby object due to shocks and friction with the lifting rope or associated abutment members is discarded.

Alternatively, the lifting device may comprise an assembly formed of a lifting drum and a lifting rope of natural and / or synthetic material, said lifting rope being fixed at one end to said drum. The lifting rope may have any of the features described above with reference to the control rope according to the invention. Thus, any risk of degradation of the object to be lifted or a nearby object due to shocks and friction with the lifting rope is discarded.

According to an alternative embodiment, said lifting device may comprise a lifting pulley and a lifting chain, said lifting chain meshing with said lifting pulley. In this case, the lifting pulley and the lifting chain have characteristics that are known to those skilled in the art.

Alternatively, said lifting device may comprise a lifting drum and a lifting cable, said lifting cable being fixed at one end to said drum. By cable means a rope entirely formed of an assembly of son of metal material, for example steel. The lifting drum and the cable In this case, the lifting devices have characteristics that are known to those skilled in the art.

Moreover, said control pulley can then be mounted fixed in translation relative to said lifting pulley or to said lifting drum.

Other advantages and features of the invention will become apparent in the detailed non-limiting description below.

BRIEF DESCRIPTION OF THE DRAWINGS

• La figure 1, déjà décrite, est une vue en perspective d'une partie d'un palan selon l'art antérieur ;
• La figure 2 est une vue en perspective d'une poulie de commande de l'appareil de levage selon le mode de réalisation préféré de l'invention ;
• La figure 3 est une vue schématique en coupe longitudinale de la corde de commande selon l'invention, munie d'une pluralité d'organes de butée ;
• La figure 4 est une vue en perspective de la poulie de commande représentée sur la figure 2, sur laquelle s'enroule partiellement la corde de commande représentée sur la figure 3 ;
• La figure 5 est une vue en perspective d'une partie de la poulie de commande dont un alvéole loge un organe de butée selon le mode de réalisation préféré ;
• La figure 6 est une vue en perspective d'une portion de corde de commande selon l'invention munie d'un organe de butée ;
• La figure 7A est une vue en coupe selon un premier plan longitudinal de ladite partie de corde de commande et dudit organe de butée représentés sur la figure 6 ;
• La figure 7B est une vue en coupe selon un second plan longitudinal orthogonal au premier de ladite partie de corde de commande et dudit organe de butée représentés sur la figure 6.

Embodiments of the invention will now be described, by way of nonlimiting examples, with reference to the accompanying drawings, in which:

• The figure 1 , already described, is a perspective view of a portion of a hoist according to the prior art;
• The figure 2 is a perspective view of a control pulley of the hoist according to the preferred embodiment of the invention;
• The figure 3 is a schematic view in longitudinal section of the control rope according to the invention, provided with a plurality of stop members;
• The figure 4 is a perspective view of the control pulley shown on the figure 2 , on which the control cord shown on the figure 3 ;
• The figure 5 is a perspective view of a portion of the control pulley including a cell houses a stop member according to the preferred embodiment;
• The figure 6 is a perspective view of a portion of control rope according to the invention provided with a stop member;
• The Figure 7A is a sectional view along a first longitudinal plane of said control rope portion and said stop member shown in FIG. figure 6 ;
• The Figure 7B is a sectional view along a second longitudinal plane orthogonal to the first of said control rope portion and said stop member shown in FIG. figure 6 .

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The hoisting apparatus according to the invention is of the type chain hoist or cable. Like the chain hoist described with reference to the example of the prior art, the hoist is intended to be suspended.

It comprises a suspension means, for example a hook, which allows it to be suspended from a hoist carriage. The truck can be moved along a monorail or a jib crane, to position the hoist at the desired location.

The hoisting apparatus comprises a lifting device for lifting an object, similar or identical to that described with reference to the example of the prior art and shown in FIG. figure 1 .

The figure 2 is a perspective view of a control pulley 12 of the hoist according to the preferred embodiment.

The control pulley 12 is coupled to said lifting device (not shown), so that the rotation of the control pulley 12 causes the lifting device to be actuated. More specifically, the control pulley 12 is coupled to the lifting device via a geared torque reducer (not shown). Said gear reducer multiplies the torque of the control pulley 12 and transmits it to the lifting device. Furthermore, a mechanical safety is provided which prevents the raised load from descending in the absence of actuation of the control pulley 12.

Said control pulley 12 has a plurality of cells 13 disposed at its circumferential surface 14, and spaced regularly from each other.

Each cell 13 is at least partially delimited by two lateral surfaces forming a stop 15A, 15B. Each abutment surface 15A, 15B extends substantially orthogonal to the circumferential axis of the pulley.

The cells 13 are interconnected by a groove 16 formed in the circumferential surface 14 of the pulley 12, which extends along the circumferential axis of the control pulley 12.

The hoist comprises transmission means whose actuation causes rotation of the control pulley 12.

The transmission means comprise a control rope 30 to which is attached a plurality of stop members 40.

The figure 3 is a schematic view in longitudinal section of a control rope 30 according to the preferred embodiment of the invention, provided with said plurality of abutment members 40.

The control rope 30 is formed of an assembly of polyamide yarns divided into four strands, and has a closed length of the order of ten meters. It has a circular overall cross section. Each strand also has a circular cross section.

It is arranged so as to be wound partly around the control pulley 12, as shown in FIG. figure 4 which is a perspective view of the control pulley shown on the figure 2 , on which the control cord shown on the figure 3 .

More specifically, the control rope 30 is housed in a portion of the groove 16 of the pulley 12, as shown in FIG. figure 5 which is a perspective view of a portion of the control pulley of which a cell houses an abutment member.

The stop members 40 are attached to said control rope 30, regularly spaced along it.

According to the preferred embodiment, and as illustrated by figure 6 , each stop member 40 is formed of two half-shells 41A, 41B assembled to each other by fastening means.

Each half-shell 41A, 41B has a half-cylinder shape of revolution. The axis of revolution of half-shells 41A, 41B coincides with the longitudinal axis of the control rope. Each is symmetrical to the other relative to the axis of revolution.

The half-shells 41A, 41B are made of rigid PVC thermoplastic. They each have a tensile strength of between 1 and 10 daN / mm ² , for example 5 or 6 daN / mm ² .

As shown in Figure 7A , the fastening means here are a screw 42 and a nut 43.

The head of the screw 42 fully fits into a counterbore formed in the outer surface of a first half-shell 41A.

The nut 43 engages entirely in an impression made in the outer surface of the second half-shell 41B. The impression has a number of lateral faces equal to the number of lateral faces of the nut 43. For example, a hexagonal footprint makes it possible to accommodate a hexagonal nut while keeping it fixed in rotation.

The head of the screw 42 and the nut 43 are fully housed in their respective housing and are not protruding from the outer contour of the half-shells 41A, 41B. They can not come into contact with the object to be lifted or a nearby object. Any risk of degradation of their fact is thus avoided.

The screw 42 extends along an axis orthogonal to the longitudinal axis of the control rope 30 and the axis of revolution of the half-shells 41A, 41B. It extends through the control rope 30. More precisely, as illustrated by the Figure 7B which is a sectional view of a stop member fixed to the control rope in a plane orthogonal to the axis of the screw 42, the screw 42 passes in a local gap between two groups of strands 31A, 31B of the rope 30. In the case of A four-strand rope, the screw 42 passes through the rope 30 so that two strands 31A pass on one side of the screw 42 and two other strands 31B pass on the other side.

To avoid any displacement of the abutment member 40 along the longitudinal axis of the control rope 30, the fastening means indirectly exert a nip on the control rope 30, through the half-shells 41A, 41B.

Indeed, the two half-shells 41A, 41B assembled to each other by the fastening means form a cylinder whose interior space can accommodate the control rope. Said internal space has, at its ends 44, 45 along the axis of revolution of the two half-shells, a diameter substantially equal to that of the control rope. Thus, the strands 31A, 31B of the control rope 30 are separated by the screw 42 and then tightened by the half-shells 41A, 41B at the ends of the interior space 44, 45, because of the clamping force exercised by the fastening means. The combination of this spacing and this tightening of the strands 31A, 31B ensures the nip of the rope 30. The stop member 40 is thus held fixed in translation along the longitudinal axis of the control rope 30.

In an alternative embodiment, the stop members are made by injection molding and may take a shape similar or identical to that of the half-shells previously described. An insert can be provided which stiffens the stop member. The insert extends through the rope in the same manner as the described screw. The pinching of the rope is then obtained, as previously, by the combined action of the spacing of the strands caused by the insert and the tightening of the latter by the stop member at the ends of said interior space.

As shown in figure 5 , the stop members of the control rope which is wound in part on the control pulley meshes with the cells of said pulley.

The actuation of the transmission means amounts to exerting a traction force on the control rope 30. The stop members 40 housed in the cells 13 come into contact with the corresponding abutment surfaces 15A, 15B. The stop members 40 then transmit the traction force applied to the control rope 30 to the control pulley 12, which causes the rotation thereof.

The torque of the control pulley 12 is then reduced and transmitted to the lifting device to ensure the lifting of the load to be lifted.

It should be noted that the tensile force can be exerted in either direction of the longitudinal axis of the control rope. Thus, an organ abutment located in a cell of the control pulley will come into contact with one or other of the two abutment surfaces of said cell to transmit said traction force to the pulley and cause rotation thereof.

Of course, various modifications may be made by those skilled in the art to the invention which has just been described, only in the context of the claims.

Claims (9)

1. Mechanical assembly, comprising:

   - a control pulley (12) comprising a plurality of compartments (13) each delimited at least partially by a surface forming a stop (15A, 15B), and

   - transmission means comprising stop devices (40) designed to engage in said compartments (13), such that actuation of said transmission means will cause rotation of said control pulley (12), due to the fact that the stop devices (40) engaged in the compartments (13) come up against the corresponding surfaces forming a stop (15A, 15B),

   wherein the transmission means comprise a control rope (30) made of natural and/or synthetic material formed from an assembly of threads and fitted with said stop devices (40),
   characterised in that each of said stop devices (40) is fixed to said control rope (30) through attachment means extending through said control rope (30).
2. Mechanical assembly according to claim 1, characterised in that said control rope (30) is formed from an assembly of threads made of a material chosen from among polyamides, polyesters, polypropylenes and polyolefins.
3. Mechanical assembly according to claim 1 or 2, characterised in that said stop devices (40) are made of a material chosen from among rubber and plastic.
4. Mechanical assembly according to any one of claims 1 to 3, characterised in that said attachment means are located inside the external contour of each stop device (40).
5. Mechanical assembly according to any one of claims 1 to 4, characterised in that each of said stop devices (40) is formed from two half-shells (41A, 41B) assembled to each other by said attachment means, said attachment means inducing squeezing of said control rope (30) between said half-shells (41A, 41B).
6. Mechanical assembly according to any one of claims 1 to 5, characterised in that said control pulley (12) comprises a groove (16) extending between said compartments (13) at the circumferential surface of said pulley (12), said groove (16) being designed to house said control rope (30).
7. Lifting equipment designed to be suspended, comprising a lifting device designed to lift an object, characterised in that it comprises a mechanical assembly according to any one of claims 1 to 6, said control pulley being coupled to said lifting device such that rotation of the control pulley (12) actuates the lifting device.
8. Lifting equipment according to claim 7, characterised in that said lifting equipment comprises:

   an assembly formed from a lifting pulley coupled to said control pulley and comprising a plurality of compartments, and a lifting rope made of a natural and/or synthetic material provided with stop devices designed to engage in said compartments of the lifting pulley; or

   an assembly formed from a lifting drum and a lifting rope made of a natural and/or synthetic material, one end of said lifting rope being fixed to said drum.
9. Lifting equipment according to claim 7 or 8, characterised in that said control pulley (12) is mounted to be fixed in translation relative to said lifting pulley or said lifting drum.

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