EP0541454A1 - Material hoist - Google Patents

Abstract

The material hoist consists of a structure (1) in the form of a ladder or of a beam, acting as a rolling track for a carriage and comprising a cable winch (3) normally used for towing the carriage. According to the invention, the towing assembly, made up of the winch (3), of the cable (5) and of a return pulley (4), is also used for righting the structure (1) and for installing it, before the normal use of the material hoist. For this purpose, the cable (5), having been disconnected from the carriage, is fastened to a fixed point (15) located at a certain height. <IMAGE>

Description

The invention relates to material lifts, of the kind consisting mainly of a ladder or beam structure serving as a rolling path for a carriage, and comprising a motorized cable winch used to tow the carriage, the cable which connects the winch to the carriage passing on a deflection pulley located on the head of said structure.

Material hoists of this kind, known for example from document FR-A-2038496, make it possible to bring loads in height, for example up to the level of the roof, during renovation or other works carried out on buildings. . There are on the one hand telescopic material lifts (see above document), and on the other hand nestable material lifts.

A telescopic material lift has a tilting telescopic ladder mounted on a trailer. It is therefore a complete lifting machine, towable behind another vehicle, which has the advantage of rapid installation. On the other hand, such a material lift remains expensive.

Nestable material lifts generally include a ladder structure, formed by a succession of elements to be assembled on site. Two distinct operating modes are commonly used on construction sites, for the implementation of this type of material lift.

The first operating method consists in assembling horizontally on the ground the whole of the structure constituting the raceway, that is to say the ladder with its head, as well as the carriage, then to manually straighten this structure in order to position it at an angle to the building. This manual operation can also be carried out using handling ropes, one of the operators taking place at a height on a roof, for example on a terrace, and the other operator guiding the foot of the ladder.

These operations are dangerous in particular for the operator who takes place on the roof, and they are difficult to perform because, although the ladder is made of light material such as aluminum, the total weight to be lifted remains significant. Because of this weight and the operating mode used, the installation of the material lift always requires the intervention of at least two people. The operations in question also require space on the ground, which poses a problem on public roads, especially in a more or less narrow street.

The second current operating mode consists in vertically assembling the structure forming the raceway. This operating mode also requires two people, the first in height pulling by a rope a first ladder element, and the second on the ground which successively hooks the other ladder elements under the first. Although it requires less space on the ground, this mounting method remains dangerous because the entire raceway, that is to say first one, then two or three ladder elements are suspended on a rope . In addition, the weight of the ladder limits the length of the raceway that can be set up in this way.

The present invention aims to eliminate the drawbacks of the operating methods currently used, by providing a provision for automating the lifting of material lifts of the type under consideration and their positioning against a building, these operations thus being facilitated and able to be carried out. by one person and safely, while maintaining a simple and economical structure.

To this end, in the material lift object of the present invention, the traction assembly of the carriage composed of the winch, the cable and the return pulley, is also provided for the straightening of said structure in ladder or beam and for its installation before normal use of the material lift, the cable being able to be disconnected from the carriage and to be hung at a fixed point located high up.

The inventive idea proposed here therefore consists in taking advantage of the trolley's pulling winch, as well as the cable winding on the winch drum and the existing deflection pulley, in order to straighten the hoist from the ground and its positioning against a building, the winch providing a motorized means suitable for this operation. The pulley ensures the return of the cable, from the horizontal initial position of the structure to its final position, which can be close to vertical, passing through all the intermediate inclined positions.

However, to thus operate the straightening of the ladder or beam structure forming the raceway, the cable return pulley must be in a vertical plane. This requirement can be fulfilled according to two constructive provisions.

On this subject, it is recalled that usually, in a hoist with ladder structure, the cable return pulley is located in a plane parallel to the plane of the scale, its axis of rotation being fixed and perpendicular to the plane of the scale. For a material hoist of this kind, the present invention provides a constructive arrangement according to which the deflection pulley has a pivoting mounting, said pulley thus being able to be moved between a first position where it is situated in a plane parallel to that of the ladder, for normal use of the material lift, and a second position where it is located in a substantially vertical plane, for the installation of the material lift.

According to another constructive arrangement, more particularly applicable to a hoist with a beam structure, the cable return pulley is mounted revolving around a horizontal axis and fixed relative to the beam structure, said pulley thus occupying a vertical position suitable for both the normal use of the material lift and for the establishment of this material lift. Indeed, the beam structure, for example of triangular section has a "thickness" sufficient for the passage of the strands of the cable, in one or other of the two uses of this cable and the winch.

In particular in this latter embodiment, the invention gives the winch, the cable and the deflection pulley an additional role, facilitating the installation of the material lift, without any additional construction cost for the material lift . In the case of an articulated idler pulley, the additional function is obtained at a relatively low additional cost, and practically negligible.

• Figure 1 est une vue en perspective d'un monte-matériaux selon l'invention, conformé en échel le, en début de montage ;
• Figure 2 est une vue similaire à figure 1, montrant le monte-matériaux en fin de montage ;
• Figure 3 est une vue similaire aux précédentes, montrant ce monte-matériaux en position de travail ;
• Figure 4 est une vue partielle du monte-matériaux des figures 1 à 3, à échelle agrandie, montrant le détail de la poulie articulée ;
• Figure 5 est une vue en coupe de cette poulie articulée, suivant V-V de figure 4 ;
• Figure 6 est une vue partielle, en perspective, d'une autre forme de réalisation du monte-matériaux selon l'invention, avec conformation en poutre de section triangulaire.

In any case, the invention will be better understood with the aid of the description which follows, with reference to the appended schematic drawing representing, by way of nonlimiting examples, two embodiments of this hoist:

• Figure 1 is a perspective view of a material elevator according to the invention, shaped in scale on, at the start of assembly;
• Figure 2 is a view similar to Figure 1, showing the material lift at the end of assembly;
• Figure 3 is a view similar to the previous, showing this hoist in the working position;
• Figure 4 is a partial view of the material lift of Figures 1 to 3, on an enlarged scale, showing the detail of the articulated pulley;
• Figure 5 is a sectional view of this articulated pulley, along VV of Figure 4;
• Figure 6 is a partial perspective view of another embodiment of the material lift according to the invention, with conformation in a triangular section beam.

Figures 1 to 3 show, very schematically, a hoist which includes a ladder-like structure 1, which may be constituted by a succession of elements nested one inside the other. The ladder 1 serves as a raceway for a carriage 2 comprising a bucket, a platform or another support adapted to the load to be moved. A motorized cable winch 3 is provided at the lower end of the ladder 1. The head of the ladder 1, opposite the winch 3, is equipped with a deflection pulley 4, over which a cable passes 5 which is actuated by the winch 3 and which is used to tow the carriage 2 along the raceway constituted by the ladder 1.

In a known manner, the material lift can also have wheels 6 at its lower end, and its upper part can form an angle with the rest of the scale 1, without the continuity of the raceway for the carriage 2 is interrupted. This hoist is usable for bringing loads in height, up to an opening 7 of a building facade 8, or on the roof of a building.

According to the invention, the traction assembly comprising the winch 3, the pulley 4 and the cable 5 can be used not only for towing the carriage 2 in the use of the material lift, but also for mounting this lift -materials, that is to say its straightening and its positioning against the building 8. For this purpose, the return pulley 4 is designed as an articulated pulley, which is shown in detail in FIGS. 4 and 5.

The terminal bar 9 of the ladder 1 carries an axis 10, parallel to this bar 9, on which is articulated a pivoting support 11. The axis of rotation 12 of the deflection pulley 4 is held by a yoke 13, which is herself pivotally mounted on the pivoting support 11 around a hinge axis 14 perpendicular to the aforementioned axis 10. Thus, the return pulley 4 can be located in a plane parallel to that of scale 1, but it can also be brought into a vertical plane and then be located above scale 1.

For the assembly of the material lift, the elements of the ladder 1 are first fitted one into the other on the ground, the cable 5 remaining initially disconnected from the carriage 2 (placed or not on the ladder 1). The end of the cable 5 remote from the winch 3 is hooked in height to a fixed point 15, which can be located on a mooring bar 16 immobilized in the opening 7, or even on a chimney or on the ridge in the case of work done on a roof. The cable 5 passes over the articulated return pulley 4 which, during assembly, remains in a vertical plane. Thus, the pulley 4 makes it possible to return the cable 5 from the start of assembly (FIG. 1) to the end of assembly (FIG. 2).

The traction of the cable 5, provided by the winch 3, ensures the elevation of the ladder 1 from its initial substantially horizontal position to its final position which can approach the vertical. It should be noted that the wheels 6 provided at the lower end of the ladder 1 facilitate the movement on the ground of the latter during its assembly, the lower end of the ladder 1 approaching the facade of the building 8.

At the end of assembly, the material lift having reached its desired position against the building 8, the cable 5 is detached from the fixed point 15 and is connected to the carriage 2, to allow the use of the material lift. As shown in FIG. 3, the articulated return pulley 4 is placed, in the working position, in a plane parallel to that of the scale 1.

Of course, the previously described arrangements also allow, at the end of use of the material lift on a given site, to bring this hoist to the ground in a motorized manner.

FIG. 6 shows another embodiment, in which the material lift comprises a truss structure 1, of triangular section. Thus, the successive elements of the structure have two upper members 17 and 18, forming the raceway for the carriage (not shown), and a lower member 19, which are connected together by bars 20 forming a triangulation.

At the head, the two members 17 and 18 are also connected by an end bar 9, which directly supports a yoke 13 holding the axis of rotation 12 of the idler pulley 4. The axis 12 is horizontal and the pulley 4 is located in the vertical median plane of the beam structure. This pulley 4 permanently occupying a vertical position ensures the return of the cable 5 both during the mounting of material lift as during its use, the principle of taking advantage of the cable and the winch to raise the material lift itself even being preserved.

It goes without saying that the invention is not limited to the sole embodiments of this hoist which have been described above, by way of examples; on the contrary, it embraces all of the variant embodiments and applications respecting the same principle. Thus, one would not depart from the scope of the invention by modifications of detail of the structure of the material lift, or by the addition of additional devices.

Claims (3)

Material lift, mainly consisting of a ladder or beam structure (1) serving as a raceway for a carriage (2), and comprising a motorized cable winch (3) used to tow the carriage (2), the cable (5) which connects the winch (3) to the carriage (2) passing over a deflection pulley (4) located on the head of said structure, characterized in that the traction assembly of the carriage (2), composed of the winch (3), the cable (5) and the deflection pulley (4), is also provided for the straightening of said ladder or beam structure (1) and for its installation before normal use of the material lift, the cable (5) being able to be disconnected from the carriage (2) and to be hooked to a fixed point (15) located in height. Material hoist according to claim 1, in particular with ladder structure (1), characterized in that the deflection pulley (4) of the cable (5) has a pivoting assembly (10 to 14), said pulley (4) thus being able be moved between a first position where it is in a plane parallel to that of the ladder (1), for normal use of the material lift, and a second position where it is in a substantially vertical plane, for the installation of the material lift. Material lift according to claim 1, in particular with a beam structure (1), characterized in that the deflection pulley (4) of the cable (5) is mounted to rotate about a horizontal axis (12) and fixed relative to the pulley structure (1), said pulley (4) thus occupying a vertical position suitable both for normal use of the material lift and for the installation of this material lift.

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