EP1908723B1 - Frame with ground-support arm for hoisting engine - Google Patents

Description

The present invention relates to a chassis with support arm on the ground for a hoist, in particular for a tower crane. Still more particularly, this invention is concerned with a frame provided with a plurality of ground support arms, generally four like-to-one support arms, articulated about vertical axes on a fixed central structure of this chassis. The invention is more specifically focused on achieving the articulated connection between each support arm on the ground and the fixed central structure of the frame.

In the field of tower cranes, there are among others cranes which rest on the ground via a fixed frame. For this type of crane, especially for self-erecting cranes, the most common ground support system consists of several support arms, usually four support arms, articulated to the central structure of the frame around vertical axes, and thus made deployable for the use of the crane and foldable against the central structure to allow the transport of the crane in a minimum footprint.

The patent French FR 1494349 illustrates such a tower crane fixed frame provided with two folding support arms. The patent French FR 2846955 , or its equivalent the patent application European EP 1418151 A , describes a tower crane fixed frame with four folding support arms.

In a usual manner, the articulation device of a support arm on the central structure of the frame, about a vertical axis, is here of the clevis-tenon type: the clevis is constituted by an angle of one upper horizontal sheet and a lower horizontal sheet of the central structure of the frame, and the pin, taking place between these two superposed sheets, is constituted by an end of the support arm. More particularly, in the embodiment according to the aforementioned French patent FR 2846955 , the connection between the support arm and the central structure of the frame comprises a massive hinge pin with enlarged lower head, the head being positioned at the bottom plate of the central structure of the frame.

Due to the presence of such a head, the mounting operations of the hinge pin, therefore the support arm itself require a reversal of the entire chassis for the introduction of this axis in the corresponding bores of the two sheets and the support arm. In addition to the flipping of the chassis, it is necessary to ensure alignment of the respective bores of the arm and the two plates of the central structure of the chassis, which is difficult because of the heavy weight of the support arm. In addition, the greater the height of the support arm, the longer the axis of articulation, so heavy and therefore difficult to handle. To limit the weight of this axis, it is known to reduce its diameter to the maximum, but there is a risk of jamming or jamming (the aforementioned French patent FR 2846955 remedying this last disadvantage).

As is readily understood, in view of the foregoing, the current devices for articulating a support arm to the central structure of the frame are specific to each support arm, and must in particular be adapted to its height. , especially with regard to the dimensioning of the hinge axis.

The document US 4397396 discloses another crane frame provided with support arms on the ground, which frame, as regards the articulation of the support arms with the central structure of said frame, already has all the features of the preamble of claim 1. In in particular, each deployable support arm comprises, in the hinge zone, a lower pivot member and an upper pivot-shaped element in the form of cylindrical bores, while means are provided for immobilizing this support arm in rotation. in a plurality of distinct angular positions, including at least one extended work position and a folded transport position.

The present invention aims to avoid all of the previously mentioned disadvantages, and is therefore intended to facilitate the mounting of the frame and in particular the support arms, eliminating the need for the flipping of the frame and a precise alignment of the arms while limiting the bracing phenomena, the proposed solution also creating a connection of the support arms with the central structure of the frame which is, without modification, usable for support arms of different heights , with a view to streamlining manufacturing.

• dans la partie inférieure du bras d'appui, un premier élément formant pivot, tel que tourillon ou alésage cylindrique ;
• dans la partie supérieure du bras d'appui, un autre élément formant pivot, tel que tourillon ou alésage cylindrique, coaxial au précédent ;
• des moyens d'immobilisation en rotation du bras d'appui relativement à la structure centrale dans au moins deux positions angulaires distinctes, incluant une position déployée de travail et une position repliée de transport ;

ce châssis avec bras d'appui au sol étant caractérisé en ce que le dispositif d'articulation comprend, en outre :

• dans la partie inférieure de la structure centrale, un élément fixe formant palier, complémentaire du premier élément formant pivot ;
• dans la partie supérieure de la structure centrale, un autre élément formant palier, complémentaire de l'autre élément formant pivot, cet autre élément formant palier étant au moins partiellement amovible ;

le palier inférieur de la structure centrale étant prévu pour recevoir l'élément formant pivot inférieur, tandis que le palier supérieur de la structure centrale est prévu pour recevoir l'élément formant pivot supérieur, l'amovibilité au moins partielle de ce palier supérieur permettant la mise en place dudit élément formant pivot supérieur, sans retournement du châssis.For this purpose, the subject of the invention is a chassis with a support arm on the ground for a hoist, in particular for a tower crane, the chassis being provided with a plurality of support arms on the ground, generally four support arms similar to each other, articulated around vertical axes on a fixed central structure of this frame, the support arms thus being made deployable for the use of the hoist, including the crane, and foldable against the central structure for the transport of the hoist, including the crane, the connection of one end of each support arm with the structure center of the chassis being formed by a hinge device which comprises, in combination:

• in the lower portion of the support arm, a first pivot member, such as a pin or cylindrical bore;
• in the upper part of the support arm, another pivot member, such as pin or cylindrical bore, coaxial with the previous;
• immobilization means in rotation of the support arm relative to the central structure in at least two distinct angular positions, including an extended working position and a folded transport position;

this chassis with support arm on the ground being characterized in that the articulation device further comprises:

• in the lower part of the central structure, a fixed element forming a bearing, complementary to the first pivot member;
• in the upper part of the central structure, another bearing element complementary to the other pivot element, this other bearing element being at least partially removable;

the lower bearing of the central structure being provided to receive the lower pivot member, while the upper bearing of the central structure is provided to receive the upper pivot member, the at least partial removability of this upper bearing allowing the placing said upper pivot member without flipping the frame.

• dans la partie inférieure du bras d'appui, un élément pourvu d'un tourillon saillant vers le bas ;
• dans la partie inférieure de la structure centrale, une demi-chape percée d'un alésage cylindrique correspondant au tourillon précité ;
• dans la partie supérieure du bras d'appui, un élément pourvu d'un tourillon saillant vers le haut, coaxial au tourillon inférieur ;
• dans la partie supérieure de la structure centrale, une demi-chape tronquée, percée d'un demi-alésage cylindrique correspondant au tourillon supérieur ;
• une plaque d'appui amovible percée d'un alésage cylindrique qui forme le complément du demi-alésage précité, des moyens
• étant prévus pour la fixation démontable de la plaque d'appui sur la demi-chape supérieure ;

l'alésage cylindrique de la demi-chape inférieure étant prévu pour recevoir le tourillon inférieur tandis que le demi-alésage cylindrique de la demi-chape supérieure, complété par l'alésage cylindrique de la plaque d'appui, est prévu pour recevoir le tourillon supérieur.According to a preferred embodiment of this frame with support arm on the ground, the articulation device comprises, for each support arm:

• in the lower part of the support arm, an element provided with a trunnion projecting downwards;
• in the lower part of the central structure, a half-clevis pierced with a cylindrical bore corresponding to the aforementioned pin;
• in the upper part of the support arm, an element provided with a trunnion projecting upwards, coaxial with the lower trunnion;
• in the upper part of the central structure, a truncated half-clevis, pierced with a cylindrical half-bore corresponding to the upper trunnion;
• a removable support plate pierced with a cylindrical bore which forms the complement of the aforementioned half-bore, means
• being provided for the removable attachment of the support plate on the upper half-clevis;

the cylindrical bore of the lower half-clevis being provided to receive the lower pin while the cylindrical half-bore of the upper half-cleft, completed by the cylindrical bore of the support plate, is provided to receive the pin superior.

• Après démontage de l'élément de palier supérieur amovible, tel que la plaque d'appui avec demi-alésage cylindrique, le bras d'appui au sol peut être aisément approché et mis en place, sans nécessité de retournement du châssis. L'alésage de la demi-chape supérieure, coopérant avec le tourillon supérieur, assure dans cette opération un positionnement correct direct du bras d'appui, résolvant les problèmes d'alignement.
• Le dispositif d'articulation comprend uniquement des éléments placés à la base et au sommet du bras d'appui, ainsi que sur la structure centrale, à l'exclusion de tout axe matériel. Les mêmes composants d'articulation sont ainsi utilisables pour des bras d'appui de différentes hauteurs (selon les efforts à transmettre), comprenant des tôles latérales plus ou moins hautes.
• Le phénomène d'arc-boutement est évité ou du moins fortement réduit en augmentant le diamètre des tourillons et des alésages correspondants, sans limitation résultant du poids d'un axe matériel.

Thus, the inventive idea here consists in providing, for the articulation of each support arm on the floor of the chassis, a clevis which results from a lower half-clevis forming a bearing without particularities, and a half-clevis upper part which has a removable part, which is removed for insert the support arm, then is put back in place and fixed to retain the support arm and form a complete upper bearing. The two bearings thus formed cooperate with pivot elements, in particular journals, which are provided at the base and at the top of the support arm, so that the hinge device does not require any material axis extending over the entire arm height. Such a design of the articulation device has the following advantageous consequences:

• After disassembly of the removable upper bearing element, such as the bearing plate with cylindrical half-bore, the support arm on the ground can be easily approached and put in place, without the need to flip the chassis. The bore of the upper half-yoke, cooperating with the upper trunnion, ensures in this operation a correct direct positioning of the support arm, solving alignment problems.
• The hinge device comprises only elements placed at the base and the top of the support arm, as well as on the central structure, excluding any material axis. The same articulation components are thus usable for support arms of different heights (depending on the forces to be transmitted), comprising more or less high side plates.
• The bracing phenomenon is avoided or at least greatly reduced by increasing the diameter of the journals and corresponding bores, without limitation resulting from the weight of a material axis.

In one embodiment of the invention, the lower part of each support arm is equipped with a lower end which comprises a connecting plate with the rest of the support arm, and a trunnion protruding under the lower face. of the connecting plate, while the upper part of each support arm is equipped with an upper end which comprises a connecting plate with the rest of the support arm, and a trunnion projecting on the upper face of the plate link. Thus, it achieves a simple and mechanically resistant embodiment of the hinge device, with lower and upper ends whose connecting plates are, in particular, fixed by welding on the lower or upper plates of the support arm, and on its side plates.

Advantageously, the upper end of each support arm has a cleat secured to the connecting plate and eccentric relative to the upper journal, the cleat being provided to abut under the upper half-clevis in the extended working position of the support arm. The cleat thus allows, in the working position, to completely eliminate the undesirable phenomenon of bracing, transmitting the shear force to the central structure of the frame.

• un alésage réalisé dans la plaque de liaison de l'embout inférieur et excentré par rapport au tourillon inférieur ;
• une pluralité d'alésages pratiqués dans la demi-chape inférieure, autour de l'alésage cylindrique de celle-ci ;
• un pion amovible prévu pour être introduit au travers de l'alésage précité de la plaque de liaison et au travers de l'un des alésages de la demi-chape inférieure.

Still in the context of the embodiment detailed here, the immobilization means in rotation of the support arm relative to the central structure of the frame may comprise:

• a bore made in the connecting plate of the lower nozzle and eccentric relative to the lower pin;
• a plurality of bores made in the lower half-yoke, around the cylindrical bore thereof;
• a removable pin adapted to be introduced through the aforementioned bore of the connecting plate and through one of the bores of the lower half-yoke.

These bores can be three in number, thus providing a choice immobilization of the support arm in the extended working position, or in the folded transport position, or in an intermediate position of mounting.

Finally, the upper half-clevis may be pierced with fixing holes, provided for the removable attachment, by means of screws, the bearing plate with cylindrical bore.

• Figure 1 est une vue d'ensemble, en perspective, d'un châssis fixe de grue à tour conforme à la présente invention, avec représentation de différentes positions des bras d'appui au sol;
• Figure 2 est une vue partielle, en perspective éclatée, du châssis de la figure 1 et de l'un des bras d'appui, montrant les composants du dispositif d'articulation ;
• Figure 3 est une vue en coupe verticale partielle du châssis de la figure 1 et de l'un de ses bras d'appui avec son dispositif d'articulation ;
• Figure 4 est une vue en perspective de l'embout inférieur appartenant au dispositif d'articulation d'un bras d'appui ;
• Figure 5 est une vue en perspective de l'embout supérieur appartenant au même dispositif d'articulation d'un bras d'appui.

The invention will be better understood from the description which follows, with reference to the appended schematic drawing showing, by way of example, an embodiment of this chassis with support arm on the ground for a lifting vehicle:

• Figure 1 is an overall perspective view of a stationary tower crane frame according to the present invention, with representation of different positions of the ground support arms;
• Figure 2 is a partial view, exploded perspective, of the chassis of the figure 1 and one of the support arms, showing the components of the hinge device;
• Figure 3 is a partial vertical sectional view of the chassis of the figure 1 and one of its support arms with its hinge device;
• Figure 4 is a perspective view of the lower nozzle belonging to the articulation device of a support arm;
• Figure 5 is a perspective view of the upper end piece belonging to the same articulation device of a support arm.

The figure 1 shows the fixed frame of a tower crane, which is composed of a central structure 2 and four support arms 3, deployable in a cross for the working position of the crane, and foldable against the central structure 2 for the transport of the crane.

The central structure 2, of generally square shape, comprises a lower horizontal plate 4 and an upper horizontal plate 5, connected by vertical welded walls 6. A hinge device 7, of circular shape, is provided in the central zone of the structure 2, for mounting a crown and a rotating frame (not shown) above which usually rises the mast of the crane, which itself carries the boom of the crane.

Each support arm 3, itself consisting of welded sheets is articulated at one end about a vertical virtual axis 8 to the central structure 2 of the frame, in one of the four corner regions of this central structure 2 The other end of the support arm 3 carries an adjustable foot 9 of support to the ground.

The device for articulating the end of each support arm 3 on the central structure 2 is in particular visible on the figure 2 and also represented in more detail on the Figures 3 to 5 , which is referred to below.

This articulation device comprises, inter alia, a lower end piece 10 shown alone on the figure 4 , which takes place substantially in the horizontal plane of the lower plate 11 of the support arm 3. Made of cast steel or forged steel, the lower end piece 10 comprises a plate 12 connecting with the rest of the support arm 3, the plate 12 having a trunnion 13 of relatively large diameter projecting normally under its lower face (the figure 3 showing the lower end 10 in the inverted position). The connecting plate 12 is also provided with a bore 14 of relatively small diameter, eccentric with respect to the axis of the pin 13. This connecting plate 12 is welded to the lower plate 11 of the support arm 3, as well as 'to its side plates.

The hinge device also comprises an upper nozzle 15, shown alone on the figure 5 , which takes place substantially in the horizontal plane of the upper plate 16 of the support arm 3, above the endpiece lower 10. Also made of cast steel or forged steel, the upper end 15 comprises a plate 17 connecting with the rest of the support arm 3, the plate 17 having a trunnion 18 of relatively large diameter, coaxial with the trunnion 13 of the lower end piece 10 and protruding on the upper face of the plate 17. The upper end piece 15 further comprises a cleat 19 of square or rectangular section, integral with the plate 17 and eccentric with respect to the axis of the trunnion 18. The connecting plate 17 is welded to the upper plate 16 of the support arm 3 and to its side plates.

On the side of the central structure 2 of the frame, and for each support arm 3, the hinge device comprises a lower half-yoke 20, constituted by the corresponding angle zone of the bottom plate 4 of said central structure 2 The lower half-clevis 20 is pierced with a cylindrical bore 21 of relatively large diameter, corresponding to the diameter of the pin 13 of the lower nozzle 10. This lower half-yoke 20 is also pierced with three bores 22, 23 and 24 relatively small diameter, arranged on the same circle centered on the axis of the cylindrical bore 21 mentioned above.

Still on the side of the central structure 2 of the frame, and for each support arm 3, the hinge device further comprises an upper half-yoke 25, of truncated shape, which is pierced with a cylindrical half-bore 26 relatively large diameter, corresponding to the diameter of the pin 18 of the upper nozzle 15. The upper half-yoke 25 is also pierced with two fixing holes 27 for a support plate (see below).

The upper half-clevis 25 is completed by a support plate 28, pierced with a cylindrical bore 29 of relatively large diameter which forms the complement of the half-bore 26. Two screws 30 are provided for the attachment of the plate. support 28 on the corresponding upper half-cleft 25, through the holes 27 above.

Finally, the hinge device comprises a removable pin 31, of diameter corresponding to that of the bores 14, 22, 23 and 24, provided for the immobilization in position of the support arm 3 (see Figures 1 and 2 ).

Referring again to the figure 1 the procedure used for the mounting of a support arm 3 will now be explained by means of the articulation device described above.

The support arm 3 is first placed parallel to one of the sides of the central structure 2 of the frame, initially devoid of its support plates 28 so as to disengage all the upper half-covers 25.

The support arm 3 is then lowered to introduce the lower pin 13 of its lower pin 10 into the bore 21 of the lower half-clevis 20. The upper pin 18 of the upper pin 15 is thus positioned in the half-bore 26 of the upper half-cap 25.

It becomes now possible to fix the support plate 28 on the upper half-yoke 25, thus to the structure 2, by means of the two screws 30. Then, the support arm 3 is rotated by an angle of rotation. 135 °, to bring it in the deployed position (according to the bisector of the corresponding angle of the central structure 2).

The introduction of the pin 31 through the bore 14 of the lower end 10 of the support arm 3, and through one of the three bores 22, 23, 24 of the lower half-yoke 20, brought in coincidence, ensures immobilization in rotation of the support arm 3 in the mounting position, or in the folded transport position of the crane, or in the extended working position of the crane.

In the extended position of work (see in particular the figure 3 ), the cleat 19 of the upper end 15 of the support arm 3 abuts directly under the upper plate 5 of the central structure 2 of the frame. The transmission of the shear force of the support arm 3 to the central structure 2 is thus effected by this cleat 19, the vertical axis 8 then transmitting only one moment which results in two equal and opposite horizontal forces .

Moreover, as is readily conceivable, the same hinge device, consisting of the two lower and upper ends 10 and 15, respectively, and the two half-yokes respectively lower and upper 25, the latter being completed by the plate support 28, can be used without modification for support arms 3 of different heights H. It is also understood that this hinge device is applicable to both support arms 3 of "monobloc" structure and therefore of invariable length, such as shown, that support arms of telescopic structure, in which case the device concerned serves for the articulated mounting of the rear element of each telescopic support arm.

• en modifiant les détails constructifs, tels que le nombre des vis de fixation des plaques d'appui, ou encore les formes de détail des bras d'appui et de la structure centrale du châssis ;
• en remplaçant l'alésage cylindrique complet de la plaque d'appui par un demi-alésage cylindrique, théoriquement suffisant pour constituer le complément du demi-alésage de la demi-chape supérieure, un alésage cylindrique complet étant cependant plus aisé à fabriquer ;
• en destinant un tel châssis non seulement à des grues à tours, mais aussi à des grues d'un type différent, ou encore à des engins de levage d'une autre nature, du moment que ceux-ci sont équipés de bras repliables et déployables d'appui au sol, notamment destinés à leur stabilisation en position de travail.

It is not departing from the scope of the present invention, as defined in the appended claims:

• by modifying the constructive details, such as the number of fastening screws of the support plates, or the forms of detail of the support arms and the central structure of the chassis;
• replacing the complete cylindrical bore of the support plate with a cylindrical half-bore, theoretically sufficient to form the complement of the half-bore of the upper half-yoke, a complete cylindrical bore being however easier to manufacture;
• by targeting such a chassis not only to tower cranes, but also to cranes of a different type, or to other lifting gear, as long as they are equipped with foldable and deployable arms ground support, in particular for stabilizing them in the working position.

Claims (7)

1. A frame with ground-support arm for a hoisting engine, in particular for a tower crane, the frame being provided with a plurality of ground-support arms (3) similar to each other, jointed around vertical axes (8) on a fixed central structure (2) of this frame, the support arms (3) thus being made deployable for the use of the hoisting engine, notably of the crane and foldable against the central structure (2) for transporting the hoisting engine, notably of the crane, the connection of each support arm (3) with the central structure (2) of the frame being achieved by a articulation device which comprises as a combination:

   - in the lower portion of the support arm (3), a first pivot-forming element, such as a trunnion (13) or cylindrical bore;

   - in the upper portion of the support arm (3), another pivot-forming element, such as a trunnion (18) or cylindrical bore, coaxial with the previous one;

   - means (14, 22, 23, 24, 31) for rotationally immobilizing the support arm (3) relatively to the central structure (2) in at least two distinct angular positions, including a deployed working position and a folded transport position;

   characterized in that the articulation device further comprises:

   - in the lower portion of the central structure (2), a fixed bearing-forming element (20, 21) mating the first pivot-forming element (13);

   - in the upper portion of the central structure (2), another bearing-forming element (25-29) mating the other pivot-forming element (18), this other bearing-forming element being at least partly removable (28, 29); the lower bearing (20, 21) of the central structure (2) being provided for receiving the lower pivot-forming element (13), while the upper bearing (25-29) of the central structure (2) is provided for receiving the upper pivot-forming element (18), at least partial removability (28-29) of this upper bearing allowing said upper pivot-forming element (18) to be set into place, without turning the frame upside down.
2. The frame with ground-support arm for a hoisting engine, according to claim 1, characterized in that the articulation device comprises, for each support arm (3):

   - in the lower portion of the support arm (3), an element (10) provided with a trunnion (13) protruding downwards;

   - in the lower portion of the central structure (2), a half-yoke (20) pierced with a cylindrical bore (21) corresponding to the aforementioned trunnion (13);

   - in the upper portion of the support arm (3), an element (15) provided with a trunnion (18) protruding upwards, coaxial with the lower trunnion (13);

   - in the upper portion of the central structure (2), a truncated half-yoke (25) pierced with a cylindrical half-bore (26) corresponding to the upper trunnion (18);

   - a removable supporting plate (28) provided with a cylindrical bore (29), which forms the part mating the aforementioned half-bore (26), means (27, 30) being provided for the attachment, which may be disassembled, of the supporting plate (28) on the upper half-yoke (25); the cylindrical bore (21) of the lower half-yoke (20) being provided for receiving the lower trunnion (13) while the cylindrical half-bore (26) of the upper yoke (25), completed with the cylindrical bore (29) of the supporting plate, is provided for receiving the upper trunnion (18).
3. The frame with ground-support arm for a hoisting engine according to claim 2, characterized in that the lower portion of each support arm (3) is equipped with a lower endpiece (10), which includes a plate (12) for connecting with the remainder of the support arm (3), and a trunnion (13) protruding under the lower face of the connecting plate (12), while the upper portion of each support arm (3) is equipped with an upper endpiece (15) which includes a plate (17) for connection with the remainder of the support arm (3), and a trunnion (18) protruding on the upper face of the connecting plate (17).
4. The frame with ground-support arm for a hoisting engine according to claim 3, characterized in that the upper endpiece (15) of each support arm (3) includes a cleat (19) firmly attached to the connecting plate (17) and excentered relatively to the upper trunnion (18), the cleat (19) being provided in order to abut under the upper half-yoke (25) in the deployed working position of the support arm (3).
5. The frame with ground-support arm for a hoisting engine according to claim 3 or 4, characterized in that the means for rotationally immobilizing the support arm (3) relatively to the central structure (2) of the frame comprise:

   - a bore (14) made in the connecting plate (12) of the lower endpiece (10) and excentered relatively to the lower trunnion (13);

   - a plurality of bores (22, 23, 24) made in the lower half-yoke (20), around the cylindrical bore (21) of the latter;

   - a removable pin (31) provided in order to be introduced through the aforementioned bore (14) of the connecting plate (12) and through one of the bores (22, 23, 24) of the lower half-yoke (20).
6. The frame with ground-support arm for a hoisting engine, according to claim 5, characterized in that the latter bores (22, 23, 24) are three in number, and thus optionally provide immobilization of the support arm (3) in the deployed working position or in the folded transport position, or further in an intermediate mounting position.
7. The frame with ground-support arm for a hoisting engine, according to any of claims 3 to 6, characterized in that the upper half-yoke (25) is pierced with attachment holes (27) provided for the attachment which may be disassembled by means of screws (30), of the supporting plate (28) with a cylindrical bore (29).

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