CZ279258B6 - Luffing jib of a crane - Google Patents

Abstract

The boom crane (11) of the three sections (12, 13, 14) has a driving rope (45) for folding and unfolding the boom (11), which connects the second section (13) to the first section (12) via a set of rods (16, 21). A rope (45) attached to the top of the rear rod (16) on the first section (12) forms a hoist (60) between the top (34) of the front rod (26) located on the second section (13) and the top (21) of the rear rod (16) . It then passes over the symmetrically placed pulleys (47, 49, 50, 53, 55, 56, 57) to a pair of pulleys (58, 59) at the top of the rear rod (16) and then winds on the drum of the winch (44) for folding and the extension of the boom (11), which is located at the rear end of the first boom section (12) (11)

Description

Technical field

BACKGROUND OF THE INVENTION The invention relates to a crane, in particular to a telescopic mast, at the upper end of which a folding boom with a cat is mounted. The boom consists of three sections which are articulated to each other. The crane includes a boom folding and unfolding device which acts on the rear holding cable, in particular by means of a boom hoist and an auxiliary cable, which is connected to an independent motor and also acts directly on the boom so that boom folding and unfolding can occur independently of extended position of the telescopic mast and in different positions during crane operation depending on its position.

BACKGROUND OF THE INVENTION

A known crane of this kind uses a driving rope for the folding and unfolding of the booms as the connecting rod between the upper ends of the front and rear members. Although this arrangement allows a single device to have two functions, i.e. to fold and unfold the boom during assembly and disassembly, and at the same time to form a connecting rod in the working position, it has the disadvantage that it does not make it possible to optimize each of these two functions. For example, if a rope is to be used as a tie rod, it is oversized for folding and unfolding; this results in oversizing of the pulley blocks and the winch, which is used for folding and unfolding the booms. In addition, the boom of this crane cannot be adjusted from the ground by simply attaching extension extensions.

SUMMARY OF THE INVENTION

It is an object of the present invention to overcome these drawbacks and to provide a new beam arrangement for folding and unfolding the booms connecting the first and second boom sections in the form of a rod assembly.

SUMMARY OF THE INVENTION The drive cable for folding and unfolding the booms is attached to the upper end of the rear boom bar on the first section and forms a hoist between the upper end of the front bar on the second section and the upper end during assembly up to the boom working position. of the rear bar, passes sequentially through the first pulley on the horizontal axis carried by the upper end of the front bar, through the second pulley on the horizontal axis carried by the upper end of the rear bar, then through the third pulley with an axis perpendicular to the axes of the other pulleys between the upper end and its horizontal axis on the first boom section, turning to the fourth pulley carried by the upper end of the rear bar and coaxial with the second pulley, passing the fifth pulley carried by the upper end of the front bar and coaxial with the first pulley and moving to at least two pulleys carried by the upper end of the rear and a thrust rod for folding and unfolding the booms, located at the rear end of the first boom section, is aligned with the second and fourth pulleys.

According to a preferred embodiment of the invention, the rear boom is of the shape of a fork, articulated at the base at the rear end of the first boom section, hinged on the upper flange of the first boom section

The stall is locked in the stowed position on the first boom section and is held in the raised position by a constant length resilient linkage that connects its upper end to the upper flange grip point on the front of the first boom section.

By analogy, a fork-shaped front boom can be articulated at the rear end of the second boom section, can be hinged to the upper flange of the second section with a lock in the folded position on the second section, and can be held in a raised position by a constant length extension rod. thus connecting its upper end with a point on the upper flange of the third boom section and bridging the upper end of the fork-shaped rod with the base pivotally mounted on the front of the second boom section.

Preferably, the rod is comprised of three parts forming a system allowing the third boom section to be folded into a second section, the first part joining the upper end of the front boom rod to the upper end of the third boom section rod, while the second and third parts are levers which are at one end, they are articulated to each other and connect the upper end of the rod of the third boom section to the anchorage point on the upper flange of the third section.

According to an additional feature of the invention, the crane comprises a device for temporarily blocking opposite ends of the upper flanges of the second and third boom sections.

The upper ends of the front and rear members are connected by a flexible rod that is taut when all three boom sections lie in a straight line in a horizontal working position.

According to a further feature of the invention, the crane comprises a rigid removable bar for interconnecting the flanges of the first and second boom sections, when the sections are perpendicular to each other and are to be joined together during assembly.

The boom can be used to extend the boom by attaching at least one extension piece from the ground without removing the crane.

Overview of drawings

In the following, the invention will be explained in conjunction with the drawings showing a preferred embodiment of a three-section folding boom of a crane and wherein:

Figure 1 shows a side view of the crane according to the invention in the stowed and stowed position; Figure 2 shows a section along II-II in Figure 1 and thus the relative position of the telescopic mast and the boom sections in the stowed position for transport;

- Fig. 3 shows a crane with a raised mast where the boom is folded parallel to the mast,

- Figures 4-9 show the individual successive stages of the unfolding of the crane,

- fig. 10 crane with telescopic mast raised and boom fully extended, in horizontal working position,

- fig. 11 the position of the boom, which makes it possible to bypass the obstacle,

-2GB 279258 B6

Fig. 12 shows the position of the crane when extending the boom with the extension piece, and Fig. 13 shows schematically in an axonometric view a cable guide for folding and unfolding the boom.

DETAILED DESCRIPTION OF THE INVENTION

The crane consists of a mobile or rigid frame 1, which carries a bogie 3 on the pivoting device 2, on which the balancing load 4 and two ropes 5, 6 for lifting and holding the telescopic mast 7 are mounted. The telescopic pole 7 consists of an outer part 8 in which the inner part 9 is slidably mounted. The telescopic pole 7 can be folded to a horizontal transport position as shown in Fig. 1 or lifted to a vertical position as shown in Figs. 3-12. In the vertical position, the outer member 8 is pivotable about a pin 10 on the front of the bogie 3. Lifting and locking devices (not shown) for the telescopic pole 7 allow for sliding movement of the inner part 9 in the outer part 8 and its locking in the raised position according to Fig. 10. However, the inner part 9 of the telescopic pillar 7 can remain slid into the outer part 8 or intermediate position.

The crane is equipped with a folding boom 11, which consists of three sections 12, 13 and 14, which are articulated together.

According to the invention, the first boom section 12 is pivoted on a horizontal axis 15 at the upper end of the inner part 9 of the telescopic mast 7 and is tilted vertically forward along the length of the telescopic mast 2, as shown in Fig. 3-8. The first boom section 12 carries a rear fork 16 in the rear end, the base of which is rotatably mounted in the pin 17, can be folded on the upper flange 18 into the transport position as well as locked in the hinge 19 in the stowed position. A resilient tie rod 20 of constant length, which is either a rope or a plurality of chain-connected elements, connects the upper end 21 of the rear rod 16 to the point 22 of the upper flange 18.

The second section 13 of the boom 11 is secured to the first section by a pin 23. The second section 13 carries at the rear end a front fork-shaped rod 26, pivotable in a pin 27 which is hinged on the upper flange 28 of the second section 13 into a transport position. in the hinge 29 in the stowed position. A constant length tie bar 30, which consists of three parts 31, 32 and 33, connects the upper end 34 of the front bar 26 to a point 35 of the upper flange 36 of the third section 14. The first tie rod part 31 is formed by a constant length cable connecting the upper end 34 of the front bar. The second two rod sections 32, 33 are two levers which are together at one end at a point 40 and connect the upper end 37 of the strut 38 to a point 35 of the upper flange 36. The division of the rod into a 33 makes it possible to fold third section 14 of boom section 13.

at the end 37 of the strut 30, the three sections 14, three parts 31, 32 are pivotally connected.

below the other

The third section of the boom 11 is articulated to the second section 13 at point 41 in the plane of the lower flanges 25, 42. In the selected position, it is held by the drawbar 30 and has all the necessary means for moving and lifting the load.

-3GB 279258 B6

The crane is equipped in a known manner with a lifting winch, a load transfer winch and an assembly winch not shown. The mounting winch ensures lifting and extending of the telescopic mast 7.

In particular, as shown in FIG. 13, the crane is further provided with a boom for folding and unfolding the booms 11 located on the first boom section 12. The drive rope 45 for boom folding and unfolding 11 is fixed at point 46 to the upper end of the rear bar 16 and passes via a first pulley 47 on a horizontal axis 48 which is mounted at the upper end 34 of the front bar 26, a second double pulley 49, 50 carried by the upper end 21 of the rear bar 16, and a third pulley 53 on the axis 54 perpendicular to the horizontal axes 51, 52, wherein the third pulley 53 is supported by the rear bar 16 and is located on the axis of symmetry of the rear bar 16 between its upper end 21 and the pin 17 on the first section 12 of the booms 11. From there the rope returns symmetrically to the fourth double pulley 55. 56, which is supported by the upper end 21 of the rear bar 16. and is coaxial with the second double roller 49, 50, from where it leads to the fifth roller 57, carried by the upper end From there, the drive cable leads to two pulleys 58, 59, which are coaxial with the pulleys 56, 55 and 50, 56. Then, the drive cable is wound onto the drum of the folding winch 44 and the pulley. The rope thus forms a hoist 60 for folding and unfolding the booms 11, which connects the upper ends 34 and 21 of the front and rear members 26, 16.

Further, the crane is provided with a hoist 61 for lifting the booms 11, which connects the rear portion 62 of the bogie 6 to the bar 64, while the end 69 of the rigid rod 66 is the attachment point of the tie rod 7 connecting the bar 64 to the upper end 21 of the rear bar 16.

In the position shown in FIG. 1, the telescopic column 7 is mounted completely horizontally, the inner part 9 is inserted in the outer part 8, the first section 12 of the booms 11 is folded onto the telescopic column 7 and the second section 13 and the third section 14 of the booms 11 along the first section 12 so as to assume the position shown in section in FIG. 2.

In the first phase (not shown), the telescopic mast 7 and the collapsed boom 11 are raised to a vertical position by a mounting winch and the outer member 8 of the telescopic mast 7 is swiveled around a pivot 10 on the bogie 8. In this position, the second section 13 and the third section 14 swivel around the upper flanges 18, 18, so as to assume the position shown in Fig. 3.

In the position shown in FIG. 3, the second boom section 13, articulated to the first section 12 on the shaft 70, is at the height of the upper flanges 18, 28 and is parallel to the first section 12, with the rear rod 16 tilted on the upper flange 18 of the first section 12 and locked in joint 19 .; the front rod 26 is then folded on the upper flange 28 of the second section 13 and locked in the hinge 29 and the strut 38 of the third section 14 is folded forward in front of the second section 13 so that the individual portions 41, 32 and 33 of the rod 30 assume a shape corresponding to the outer shape second and third sections 13, 14 of the booms 11.

-4GB 279258 B6

In the second phase, the inner part 9 of the telescopic pole 7 is telescopically extended from the outer part 8, the first boom section 12 is lifted and the boom 11 unfolds independently and without affecting the position of the two parts 8, 2 of the telescopic pole 7. series of crane operating positions. A preferred embodiment of the assembly is illustrated in Fig. 4-9.

When the crane is in the position shown in FIG. 3, the rope 45 unwinds the winch 44 for folding and unfolding the boom 11. The hoist 60, which connects the upper ends 21 and 34 of the rear rod 16 and the front rod 26 via pulleys 49, 50 and 55, 53 and The pulleys 47, 57 extend and, under the weight of the two sections 13 and 14, the sections swivel around the shaft 74 until the lower flanges 24, 25 of the first section 12 and the second section 13 touch their ends as shown in FIG. 4. During this interval, the third section 14 deviates from the second section 13 by the action of a rod 30 which is connected to the strut 38, pivoting about the gripping point 41 to which it is attached to the second section 13.

A bolt 23 is fastened from the ground which connects the lower flanges 24, 25 of the first section 12 and the second section 33, thereby connecting the two sections into one body. Then, the rope 45 of the hoist 60 is loosened slightly by the winch 44 and the joint 29 is released, which locks the front rod 26 on the second section 13 of the boom 11. In the position of Fig. 5 the front rod 26 has been unlocked. causes the front rod 26 to rise and then raise the third boom section 14, which pivots around the gripping point 41 on the second section 13 by the drawbar 30 to lift the strut 38. At the end of this phase, the second section 13 and the third section 14 of the boom 11 one line and are joined together by a bolt 75 at the point where their upper flanges 28, 36 are joined, as shown in FIG. 6.

In this further position, the shaft 74 connecting the upper flanges 48, 28 of the first section 12 and the second section 13 of the boom 11 is released. By unwinding the rope 45 of the hoist 60 from the winch drum 44 the second section 13 and the third section 14 is pivoted .

In the position shown in FIG. 7, the second section 13 and the third section 14 of the boom 11, which actually form one body, are substantially horizontal and perpendicular to the first section 12, which remains in a vertical position along the telescopic mast 2. 13 and a third section 14 with a first section 12 by inserting a rigid rod 76 between the opposite ends of the upper flanges 18, 28.

The rope 45 of the hoist 60 is then slightly let loose from the winch drum 44, the joint 19 which blocks the rear rod 16 on the first section 12 of the boom 11 is loosened, and is directly pushed by the rear hoist 61 and the hoist or 9 from the outer part 8 of the telescopic column 7 pivots the rod 64 around the hinge 67, located at the rear on the inner part 9 of the telescopic column 7. The tie rod 73 is then tensioned, which connects the rod 64 to the upper end 21 of the rear bar 16, which is erected until the elastic tie rod 20 is tensioned as shown in FIG. 8.

In this new position, the rope 45 of the chain block 60 is slightly tensioned by the winch drum 44, the rigid rod 76 which connects the second

The position of the booms 11 and the individual positions are adjusted at the same time or by successive pulling of the hoist rope 61 used for lifting the booms 11 and the boom 60 for folding and unfolding the booms 11. The second section 13 and the third section 14 are connected with respect to the first section 12. One of these positions is shown, for example, in FIG. 9.

Then, the hoist rope 61 is further pulled until the first boom section 12 arrives in the horizontal position and the hoist rope 45 is tensioned until all three boom sections 12, 13, 14 lie flush in the horizontal working position. The upper ends 34 and 21 of the front rod 26 and the rear rod 16 are connected by a flexible rod 77 which is tensioned when all three sections 12, 13, 14 are in line and serve as a connecting rod as indicated in FIG. 10. .

From the position shown in FIG. 10, by pulling the rope 45 of the hoist 60 by winding it onto the winch drum 44, the second section 13 and the third section 14 can be lifted from the first section 12, for example to avoid the boom 11 avoiding an obstacle 63 during operation. Fig. 11.

The cantilever pulley 60 also extends from the ground, without dismantling the crane, simply by attaching extension extension 78 or a plurality of such extension pieces to the front end of the third boom section 14.

The tipping crane according to the invention, provided with a hoist 60 for folding and unfolding the booms 11, has a convenient shape and allows for an increase in load capacity.

It goes without saying that the folding of the crane from the unfolded working position proceeds in the reverse sequence of the same procedures as described in connection with the unfolding.

The drive rope 45 for folding and unfolding the booms 11 may pass from one to the other of a pair of double pulleys 49, 50 and 66, 56 which are supported by the upper end 21 of the rear bar 12 depending on the shape of the booms 11. During the phase corresponding to FIG. 7, the rope 45 runs along the pulleys 50 and 56. · When the rear bar 16 is lifted, the rope 45 gradually leaves the pulleys 50, 56 and passes to the pulleys 49, 55. It then slides over them during the phases corresponding to FIG. 8. -12.

As can be seen from the foregoing, the lifting and unfolding of the booms 11 can take place in any position and at any stage of the telescopic mast extension. 7. In particular, in the absence of a hoist to lift the booms 11 on the post retaining pole, the telescopic mast 7 during the first phase of tensioning the rear holding rope between the end 69 of the rod 64 and the rear portion 62 of the bogie 3 and in the second phase of raising the booms 11 in a more or less distributed position according to the force exerted on the hoist 60 for folding and unfolding the booms 11.

Of course, the invention is not limited to the embodiment shown, and in particular includes a variety of structural equivalents corresponding to rods 20, 30 and 77.

Claims (8)

PATENT CLAIMS Crane folding boom consisting of three articulated sections connected to one another and having at least one folding and unfolding driving cable connecting the second boom section to the first boom section by means of a rod assembly, characterized in that the folding and unfolding driving cable (45) is connected to the upper end (21) of the rear bar (16) mounted on the first section (12) of the boom (11) from where it passes sequentially over the first pulley (47) on the horizontal axis (48) carried by the upper end (34) of the front bar (26) mounted on a second section (13) of the boom (11), via a second pulley (49, 50) on horizontal axes (51, 52) supported by the upper end (21) of the rear bar (16) of the boom (11), a third pulley (53) on an axis (54) perpendicular to the horizontal axes (51, 52), a fourth pulley (55, 56) supported by the rear bar (16) and positioned in a plane between the upper end (21) of the rear bar (16); coaxial with the second pulley (49, 5 0), passes to a fifth pulley (57) supported by the upper end (34) of the front bar (26) of the boom (11) and coaxial with the first pulley (47) and to a system of at least two pulleys (58, 59) supported by the upper end ) a rear bar (16) of the boom (11) and coaxial with the second and fourth pulleys (49, 55); 50, 56) and from there to the winch drum (44) located at the rear end of the first boom section (12). A crane tipping boom according to claim 1, characterized in that the rear bar (16) is fork-shaped, pivotable at the rear end of the first boom section (12), is hinged on the upper flange (18) of the first section (12). locked in this stowed position, wherein an elastic link (11) is arranged between the upper end (21) of the rear boom (16) and the point (22) on the upper flange (18) of the front of the first section (12) of the boom (11). 20) of constant length. A crane tipping boom according to claim 1, characterized in that the front bar (26) is fork-shaped, pivoted at the rear end of the second boom section (13), is hinged on the upper flange (28) of the second section (13). locked in this stowed position, a constant rod (30) being arranged between the upper end (34) of the front boom member (11) and the point (35) on the upper flange (36) of the third boom section (14) a length that bridges the upper end (37) of the fork-like strut (38) with its base pivotally mounted on the front of the second section (13) of the boom (11). A crane tipping boom according to claim 3, characterized in that the drawbar (30) consists of three parts (31, 32, 33) and a first cable part (31) is arranged between the end (34) of the front bar (26) of the boom (11). and the upper end (37) of the strut (38), while the rod parts (32, 33) are formed by two levers connected at one end to each other. Crane folding boom according to one of Claims 1 to 4, characterized in that it is provided with a bolt (75) arranged at opposite ends of the upper flanges (28, 36) of the second The section (13) and the third section (14) of the boom (11) are temporarily locked. A crane tipping boom according to any one of claims 1 to 5, characterized in that the upper ends (21, 34) of the rods (16, 17). 26) are connected by a flexible rod (77) which is tensioned in the horizontal working position of all three sections (12, 13, 14) of the boom (11) · Crane folding boom according to one of Claims 1 to 6, characterized in that for the perpendicular connection of the boom sections (12, 13) to one body during assembly, they are at opposite ends of their upper flanges (18, 28). provided with a rigid removable rod (76). A crane tipping boom according to claim 1, characterized in that the second and fourth pulleys (49, 55, 50, 56) are double pulleys.