Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
  • B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
  • B66C23/18—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes
  • B66C23/26—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes for use on building sites; constructed, e.g. with separable parts, to facilitate rapid assembly or dismantling, for operation at successively higher levels, for transport by road or rail
  • B66C23/34—Self-erecting cranes, i.e. with hoisting gear adapted for crane erection purposes
  • B66C23/342—Self-erecting cranes, i.e. with hoisting gear adapted for crane erection purposes with telescopic elements
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B66—HOISTING; LIFTING; HAULING
  • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
  • B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
  • B66C23/18—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes
  • B66C23/26—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes specially adapted for use in particular purposes for use on building sites; constructed, e.g. with separable parts, to facilitate rapid assembly or dismantling, for operation at successively higher levels, for transport by road or rail
  • B66C23/34—Self-erecting cranes, i.e. with hoisting gear adapted for crane erection purposes
  • B66C23/348—Self-erecting cranes, i.e. with hoisting gear adapted for crane erection purposes the erection being operated by jacks

Definitions

• the present invention relates to self-erecting tower cranes with telescopic poles, foldable for transport on the road, and this invention relates more particularly to a mast lifting device for such a crane, that is, that is to say a device which allows the telescopic mast to be straightened, by moving it from a substantially horizontal transport position to a vertical working position, the lifting of the mast being accompanied by that of the boom of the crane, carried by the mast.
• a self-erecting tower crane, with telescopic mast usually comprises a fixed or rolling base frame supporting, by means of an orientation device, a rotating frame which itself supports the telescopic mast generally constituted two or three elements mounted sliding one into the other.
• the connecting means, provided between the rotating frame and the lower and outer mast member, are designed to allow the raising of the mast and, consequently, the training of the assembly consisting of the mast and the boom, this in a continuous movement.
• This articulated double link induces a lift kinematics which makes it possible to maintain the center of gravity of the moving parts as close as possible to the center of the lifting polygon.
• the front stays can be connected together, as well as the rear stays. These stays are connected to the lateral faces of the mast, or to the front of the mast.
• Such a lifting device has a bulk width width, resulting from the lateral arrangement of the stays. It also has the particularity that the space between the ground surface and the lower part of the structure of the crane decreases during the lifting; this results in difficulties for the broaching and unplugging of the rear transport train of the crane, or difficulties in case of crowded construction site.
• the device still requires connecting pieces between the mast and the transport equipment, and it also requires separate drive means, on the one hand for lifting the mast and on the other hand for telescoping the mast.
• this known device has a small range of postage, for laying the front and rear supports of the base frame.
• the volume and length of the mast foot make the free space between the ground and the weak mast foot, when the crane is in the transport position, hence the need for transport equipment lowers and attached very backward, which limit the rear clearance angle, causing difficulties access to construction sites.
• the efforts to be exercised during the lifting require a powerful motorization.
• the present invention aims at eliminating the disadvantages of the devices described above, by providing a mast lifting device which is compact and simpler, and which facilitates and makes safer the operations of positioning and lifting the crane , as well as its transport.
• the mast lifting device comprises a single front seat with profiles symmetrical with respect to the vertical median plane of the rotating frame and the mast, two rear stays symmetrical to each other by relative to this median plane, a single jack located in said median plane and stitched by a first end at an intermediate point of the front stay, a transverse bar mounted at the other end of the jack, and two symmetrical pairs of lateral rods connected by trunnions respectively on both sides of the rudder bar, each pair of connecting rods comprising a smaller link rod articulated with the lower and outer member of the telescopic mast, and a longer connecting rod hinged with the front stay at a point near the articulation of the latter with the lower and outer element of the telescopic mast.
• the front stay is composed of two parallel beams, symmetrical with respect to the above-mentioned vertical median plane and rigidly connected to each other by a cross-member, to which is affixed the first end of the jack, which takes place between the two. beams.
• a such double but monobloc front stay, associated with a single jack, has the advantage of ensuring the stability of the assembly, even in the case of a load distributed asymmetrically with respect to the vertical median plane.
• the tower crane shown schematically in FIG. 1, comprises, in a known manner, a fixed base frame 1 supporting, via a device 2, a rotating frame 3 which carries a counterweight at the rear 4.
• the rotating frame 3 supports, at the front, a telescopic mast 5 which consists of three elements, namely a lower and outer element 6, an intermediate element 7 and an upper and inner element 8, all of section for example square or polygonal.
• This crane is provided with a distributing arrow 9 with carriage 10, carried by the top of the upper element 8 of the telescopic mast 5, and held in a horizontal position by a rear retaining device 11 connected to the rear part of the rotating frame 3 .
• a mast lifting device generally designated by the reference 12, provides the connection between the rotating frame 3 and the lower and outer element 6 of the telescopic mast 5 (this element 6 is not articulated directly on the rotating frame 3), and allows the mast 5 to be brought into the vertical working position, starting from the horizontal position of the position shown in FIG. 2, and vice versa.
• the lifting device 12 consists mainly of a front stay 13, two rear stays 14, a jack 15 and a system of rods 16 and 17.
• the front stay 13 is articulated by a first end, about a horizontal axis 18, to the front part of the rotating frame 3.
• the other end of the front stay 13 is hinged to the lower and outer member 6 of the telescopic mast 5 along a horizontal axis 19 located at the rear of the mast element 6, more particularly outside the rear face 20 of this mast element 6.
• the front stay 13 is composed of two parallel beams 21, symmetrical with respect to the vertical median plane P of the rotating frame 3 and the mast 5, the two beams 21 being secured to one another by a cross member 22 located at a short distance from the first end of the front stay 13.
• the two rear shrouds 14 are parallel and symmetrical with respect to the vertical median plane P.
• Each rear shroud 14 is hinged at one end, along a horizontal axis 23, at an intermediate point of the rotating frame 3, relatively close to its rear portion.
• the other end of each rear stay 14 is articulated, along a horizontal axis 24, to the lower and outer part 6 of the telescopic mast 5.
• the hinge pin 24 is located outside the rear face 20 of this mast element 6, above the hinge axis 19 of the front stay 13 with the same mast element 6.
• the jack 15 which is a double-acting hydraulic jack, is located in the vertical median plane P.
• the body 25 of the jack 15 is pinned at one end to the cross member 22 of the front stay 13, so that the jack 15 takes place between the two beams 21 of the front stay 13.
• the rod 26 of the jack 15 carries, at its outer end, a transverse beam 27, having a horizontal pin 28 at each end.
• the linkage system comprises two pairs of rods 16,17, symmetrical with respect to the vertical median plane P, the two connecting rods 16 and 17 of each pair being of unequal lengths.
• the rod 16 of smaller length is hinged, at one of its ends, on the trunnion 28 and, at its other end, along a horizontal axis 29, on the corresponding side of the lower and outer element 6 of the telescopic mast 5; the hinge axis 29 of the connecting rod 16 is located at an intermediate level between the respective hinge pins 19 and 24 of the front stay 13 and the rear stays 14 with the mast element 6.
• the connecting rod 17 of larger length is articulated, by one of its ends, on the pin 28 and, at its other end, along an axis horizontal 30, at the front stay 13; the hinge axis 30 of the connecting rod 17 is relatively close to the hinge axis 19 of the front stay 13 with the mast element 6.
• the actuation of the jack 15 in the direction of the output of its rod 26 controls the lifting of the telescopic mast 5, from its horizontal position of setting (FIG. 2) to its vertical working position (FIG. a continuous deformation movement of the quadrilateral defined by the rotating frame 3, the front stay 13, the rear stays 14 and the mast member 6, the movement being effected through intermediate positions, one of which is shown on the 3.
• FIG. 2 When the telescopic mast 5 is fully straightened, the lower end of its lower and outer element 6 is secured, by a broach 31, with the front stay 13.
• the lowering of the telescopic mast 5 and its horizontal setting, for the purpose of transporting the crane, is carried out by actuating the jack 15 in the opposite direction of the lifting, that is to say in the direction of the retraction of its rod 26, after having disengaged the lower part of the mast 5 of the front stay 13 by removing the broach 31.
• the cylinder 15, providing the motorization of the lifting of the telescopic mast 5, can also be used for the motorization of the telescoping function of this mast 5.
• the spreader 27 mounted at the end of the rod 26 of the jack 15 and connected to the connecting rods 16 and 17 constitutes a fixed point, while the body 25 of this jack 15, desolisarisé of the crosspiece 22 and connected to a muffle 32, constitutes the mobile part of a haulage whose second muffle 33 is secured to the base of the front stay 13 (see Figure 4).

Landscapes

• Engineering & Computer Science (AREA)
• Structural Engineering (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Jib Cranes (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=9506009

Family Applications (1)

Country Status (6)

Cited By (1)

Families Citing this family (5)

Family Cites Families (5)

• 1997
  • 1997-04-11 FR FR9704718A patent/FR2761970B1/fr not_active Expired - Fee Related
• 1998
  • 1998-04-01 ES ES98420057T patent/ES2190049T3/es not_active Expired - Lifetime
  • 1998-04-01 EP EP19980420057 patent/EP0873964B1/fr not_active Expired - Lifetime
  • 1998-04-01 DE DE1998610981 patent/DE69810981T2/de not_active Expired - Lifetime
  • 1998-04-08 RU RU98106095A patent/RU2191156C2/ru not_active IP Right Cessation
  • 1998-04-10 JP JP9898298A patent/JPH10279281A/ja active Pending

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