FR2461678A1 - MOBILE LIFTING CRANE MOUNTED ON CROWN - Google Patents

Abstract

THE INVENTION RELATES TO A CRANE INCLUDING FRONT AND REAR PAIRS OF TRACK ASSEMBLIES. THE FRONT PAIR OF TRACK ASSEMBLIES, ONE OF WHICH IS REPRESENTED IN 47, FORM AN INDEPENDENT SELF-PROPELLED CARRIER DEVICE WHOSE TRACKS CAN BE CONTROLLED SELECTIVELY AND IN A REVERSIBLE MANNER TO ALLOW FORWARD AND BACKWARD MOVEMENTS, AS WELL AS BACKWARDS. ROTATING MOVEMENTS. THE TWO TRACK ASSEMBLIES OF THE REAR PAIR, ONE OF WHICH IS REPRESENTED AT 68, SUPPORT THE REAR PART OF CRANE 10. THE TRACKS OF THESE LATEST ASSEMBLIES ARE MOUNTED SO THAT THEY CAN TURN FREELY. FIELD OF APPLICATION: CRANES FOR HEAVY LOADS.

Description

The invention relates generally to hoisting cranes, and more

especially a mobile crane

mounted on crown.

  In response to the ever-increasing needs of users, self-propelled cranes have been built to lift ever-increasing loads. Although a number of factors are involved in determining the capacity of a crane, a fundamental limitation results from the fact that the weight of the crane and its load must inevitably be transmitted to the ground in a stable manner and that, if you wish to rotate the load, the connection between the crane and the ground must be stable throughout the entire arc

rotation of the crane.

  A significant increase in crane capacity was achieved by a self-propelled crane equipped with the support crown and extended boom support described in US Pat. Nos. 3,485,383 and 3,878. 944. According to this conception, the weight of the crane and its load is transmitted to the ground by means of a large diameter crown, forming a track. As described in the aforementioned patents and as practiced industrially for several years, the support ring is either locked in place by means of wedges of wood adjusted and wedged under the crown, all around its periphery, is supported by several jacks

  spaced along the periphery of the crown.

  Other improvements to cranes

  mounted on a crown are described in US Pat.

  United States No. 4,042,115 and NI 4,103,783. These patents indicate, inter alia, that an independent transport mechanism can be secured to a crane mounted on a ring, otherwise fixed, and detached from this crane for

  allow it to move between different locations.

places or workplaces.

  The invention relates primarily to a crane having a superstructure which pivots on a lower chassis of vehicle to which are attached two support rails which are part of this frame. A track crown is attached to the side members and horizontally surrounds the lower frame. An arrow support is mounted so that it can pivot vertically on the superstructure and be rotatable on the crown. An arrow, mounted on this support, allows to lift a load. A support of

  counterweight is mounted so that it can pivot vertically

  on the superstructure - and turn on the crown. Elements interconnect the counterweight support and the boom, and a movable carrier for the crown and the crane includes front and rear pairs of laterally spaced track assemblies disposed proximate the ends of the two

  beams. Organs, which include elements corresponding to

  chassis, connect the tracked assemblies of each of the front and rear pairs and

  support the crown between the ends of the side members.

  Each crawler assembly of the forward pair of crawler assemblies includes an endless crawler and a hydraulic motor device for selectively and reversibly driving the crawlers to allow the crane and crown to be moved over the crawler. ground while

the arrow raises a load.

  The invention will be described in more detail with reference to the accompanying drawings by way of non-limiting example and in which: - Figure 1 is a partial elevation of the support structure of a crane according to the invention; and FIGS. 2 and 3 are partial sections respectively along the lines 2-2 of FIG. 1 and 3-3

of Figure 2.

  The figures show a crane 10 which has a superstructure 11 mounted to be rotatable on a vehicle frame 12 via a raceway 13. To increase the capacity of the crane 10, a

  crown 15 forming a track is attached to the ends of the

  16 and 17 so as to surround horizontally

  the chassis 12 of the vehicle. The ring preferably has a cross section similar to that of an I-beam whose upper surface, forming a track, is cured. To adapt the crane to this annular support configuration, the longitudinal members 16 and 17 are fixed to the frame 12 of

to be united.

  The geometry of the crane 10 helps to give the latter a high capacity when used with the support ring. An arrow support 25 is mounted so as to be able to pivot vertically on the superstructure 11 and has a bearing assembly 26 intended to rotate on the ring gear 15. An arrow 27 is mounted on this support at a point constituting the lifting pin 28. system load, and a load lifting cable 29 is disposed along the boom 27 on the end of which it passes. A counterweight support 31 is also mounted to be vertically pivotable at 32 on the superstructure 11 and this support extends in the opposite direction to that of the boom support 25 so that it can move on the crown 15 by means of 33 bearing assemblies of which only one is shown. Counterweights 34

are stacked on the support 31.

  In fact, the entire structure located on

  the side of the pivot 28 opposite to that of the arrow serves for the equi-

  and a stabilization of the crane 10. A mast 36 is preferably mounted on the support 25 and a guy 37 lifting the boom interconnects the tops of the mast 36 and the boom 27 so that the latter can be moved vertically. The mast 36 is fixed by means of trays 38 to an easel 39 disposed on the superstructure 11 to form a substantially rigid assembly, and other traps 41 provide relatively rigid connections between the

  counterweight support 31 and the top of the mast 36.

  toises 42 determine the substantially fixed angular position of the mast 36. This geometry gives the crane a great deal of

ability and good stability.

  A movable carrier device 45- is adapted to support the ring 15, below the pivot 28, to allow the crane 10 and the crown 15 to move on

  the ground while the boom 27 raises a heavy load.

  In the preferred embodiment, the movable carrier device 45 comprises two laterally spaced sets of tracks 46 and 47 disposed respectively near the forward ends of the support beams 16 and 17. The track assemblies 46 and 47 are interconnected by a

  frame member or chassis 48 of the vehicle which itself

  same, is articulated on a frame member 51 carrying the ring 15. The frame member 51 is preferably connected to the frame 48 of the vehicle by a turntable 52 and at the

  15 by several legs and shear plates 53-

  is lying. When a heavy load is lifted by the boom 27, the forces are transmitted downwards by this arrow 27 and the mast 36 to the support 25 of the arrow which moves on the ring 15, close to the pivot 28. The forces lifting are also transmitted by the pallets 41 to the counterweight 34 stacked on the support, which tends to lift the support 31 of the ring 15. Since the element 51 of the fixing frame supports the ring 15 near the pivot 28, the lifting forces are directed mainly downwards and transmitted by the crown 15 to the carrier device, and the sets 46 and 47 tracked

  resist them by resting on the ground.

  Each of the track assemblies 46 and 47 is independently controlled to move the crane 10 under load by selective and reversible drive of the tracks 46 and 47, for example by means of independent hydraulic motors 66 and fixed and variable displacement, respectively, as

  described in U.S. Patent No. 4,000,784.

  The use of these motors 65 and 66 not only increases the traction power of the crane 10, because the load is mainly based on the tracks 46 and 47, but also provides a firmer directional control when the

  crane 10 moves following a curve.

  The rear part of the crown 15 comprises a carrier device 67 which is intended to support this

  crown while traveling and withstand rocking

  the crane 10 and the crown 15 to the rear when the boom 27 does not bear-loads. It is thus unnecessary to remove certain parts of the counterweight 34 of the support between successive heavy lifting operations. The carrier device 67 preferably comprises two crawler assemblies 68 and 69, spaced laterally and disposed respectively close to the rear ends of the longitudinal members 16 and 17. These track assemblies are connected to each other by a cross member 70 on which

  the back part of the crown rests.

  It should also be noted that the movable carrier device 45 and the carrier device 67 can be quickly and conveniently connected to a normal crane supported by a crown, and detached from this crane, as described in US Pat. 4 103 783. As stated in this patent, several support arms 71 of the

  crown are mounted so that they can pivot vertically

  on the vehicle frame 12 and protrude outwardly to pass below the ring 15 at spaced points along the periphery thereof. Several cylinders 72 are each disposed on one end of an arm 71, these cylinders 72 being dimensioned so as to bear against the ground when they are in extension and to lift the crown 15 and the chassis 12 of the vehicle from the ground. To facilitate the positioning of the crown

  , hydraulic cylinders 73 are mounted at the four ends.

  mtres 16 and 17 support rails. Maneuvering these jacks 73 allows the crown 15 to be raised and leveled, which allows the manual cylinders 72 to be brought rapidly into the extended position to firmly support the crown, over its entire periphery, and to facilitate

  mating and uncoupling operations of the

  Mobile carrier 45 and / or carrier device 67.

  It goes without saying that many modifications can be made to the crane described and shown without

depart from the scope of the invention.

2461 678

Claims (5)

RiEVENDICATIONS   Crane comprising a superstructure (11) which can pivot on a lower chassis (12) of vehicle to which are attached two longitudinal members (16, 17) of support so as to be secured to the frame, a ring (15)   forming track being attached to the spars and surrounding horizon-   the lower frame, an arrow support (25) being mounted so as to be vertically pivotable on the superstructure and rotatable on the crown, an arrow (27) being mounted on the support so as to lift a load, a counterweight support (31) being mounted so as to be vertically pivotable on the superstructure and rotatable on the crown, elements connecting the counterweight support and the boom, the crane being characterized in that has movable carrier devices (45, 67) for supporting the crown and the crane and includes front pairs (46, 47)   and rear (68, 69) tracked assemblies spaced laterally   and respectively arranged near the ends of the two side members, and members which comprise respective frame members (51, 70) interconnecting the track assemblies of each of the front and rear pairs and for supporting the ring between said ends. spars, each track set of said front pair of track assemblies comprising an endless track and a hydraulic motor (65 or 66) for selectively and reversibly driving the track to allow the crane and the crown to move on the floor   while the boom raises a load.   Crane according to claim 1, characterized in that the front pair of track assemblies (46, 47) is connected to the frame members via a   pivot axis mechanism and turntable (52).   Crane according to claim 1, characterized in that the front pair of tracked assemblies (46, 47) is constructed to form an independent self-propelled bearing device which can be easily attached to the crown and separated from the latter. 2-4 6 1 6 7 8   4. Crane according to claim 1, characterized in that the rear pair of track assemblies (68, 69) comprises tracks mounted so as to rotate freely. Crane according to claim 1, characterized in that   hydraulic cylinders (73) are arranged at the ends   between the two support spars in order to raise and lower the front and rear pairs of chenilles.-