FR2553396A1 - Telescopic jib for a crane, aerial work platform, or platform - Google Patents

Abstract

Telescopic jib for a crane, aerial work platform, or platform, of the type comprising a basic element 1 and several movable elements 2, 3, 4, the first movable element 2 being developed by a jack 40, and the second movable element 3 being developed by a traditional chain 9 and return pulley 11 device. A flexible pipe 16 for hydraulic fluid is fixed on and along the chain 9. It supplies a second jack 41 fixed between the third 3 and fourth 4 element and allows this fourth element to be developed. A pin 54 makes it possible to lock the two last elements in a relative position, and thus to lock the jack 41 in position. Thus, by virtue of a pipe 47 linked to the body of the jack 41 and to a rapid take-up member 59 situated in the head of the jib, it is possible to supply a complementary piece of equipment fixed onto the head of the jib with pressurised hydraulic fluid.

Description

Telescopic boom for crane, platform or platform
The present invention relates to a telescopic boom for crane, nacelle or platform, of the type comprising a base element and at least two movable elements, the first element being developed by a jack and the second movable element being developed by a channe device. or cable driven by the displacement of the first movable element.

The development of telescopic arrows with three elements of which two telescopic usually takes place, as can be seen for example in Figure 1 of Patent FR-A-2,390,368, as follows
A hydraulic cylinder placed inside the elements has its rod fixed on the base element and its body fixed to the first movable element.

The pressurized oil supply is done by the cylinder rod and allows to telescope the first mobile element.

 A cable, or set of cables, or a chain, or set of chains, has an end attached to the base of the base element, passes hairpin on a pulley, toothed wheel, or roller, integral with the end the body of the cylinder, and at its other end fixed to the foot of the second movable element. What is commonly known as a proportional or synchronized output of the two moving elements with respect to the base element is then obtained. The synchronized development of the second mobile element can also be obtained by other cable devices (s) or channe (s) totally equivalent where only are different the position of the pulley, toothed wheel, or roller, still integral nevertheless with the first movable element, as well as the position of the point of attachment of the cable or chain on the base element, this position being nevertheless always such that the cable, or the like, is wound in a hairpin around the pulley, or the like.

 Whether this type of three-section telescopic boom is used as a crane boom or as a platform support or personnel platform, it is increasingly demanded that they also offer the possibility of having a hydraulic power supply. arrowhead to feed, if desired, one or more additional equipment. One of the objects of the invention is to offer this possibility by means particularly simple, reliable, and inexpensive.

 Moreover, when this type of telescopic boom is used as platform support or platform, it is known that the legislation of many countries requires to provide a security against an accidental re-entry of the second mobile element in case of rupture of its device. synchronized development with cable (s) or catna (s).

 One of the objects of the invention is to use, by adapting them, the preceding means for fulfilling this safety function.

The development of four-element telescopic arrows, including three moving elements, is generally carried out as follows
A first hydraulic cylinder placed inside the elements has its body fixed to the base of the base element and its rod fixed to the foot of the first movable element. Its supply of hydraulic fluid pressure thus allows to develop in bulk the package constituted by the three movable elements.

 A second hydraulic cylinder and a conventional device with cable (s) or chain (s) are arranged in the set composed of the three movable elements in the same way as they are in the three-element arrows described above. They therefore develop the three moving elements in the manner previously described, but said second cylinder, because it moves with the first movable element, must be supplied with hydraulic fluid using a hydraulic hose reel located at foot of the arrow.

 Such a device therefore requires a hose reel and a first cylinder sufficiently sized to support the load due to the entire boom. It also lacks flexibility because it does not allow the maneuvering completely independent of the last movable element, which is very useful for some work, in particular, as will be seen later, if using a variable flyer .

 Another object of the invention is to propose a four-element telescopic boom including three movable elements, in which the third mobile element is developed independently by means of a jack located between itself and the second movable element. this telescopic boom also offering the possibility of having one or more hydraulic fluid supplies at the boom head in order to supply one or more additional equipment. In the case of using such a telescopic boom to support a nacelle or platform, the object of the invention is also to propose, as for the previous three-element boom, adapting these supply means by flexible conduit for also play them the role of safety in case of failure of the cable device (s) or chatne (s) developing the second mobile element.

 The invention is obviously not limited to an arrow with three or four elements. A fifth element could very well be added to the four-element boom of the invention, being developed by the same cable device (s) or singing (s) as that developing the third dement, always with availability of a hydraulic feed at the boom head and safety in case of failure of the rope device (s) or chain (s).

 Similarly a sixth element developed by jack as the fourth element could be added, then optionally a seventh element also developed by cable (s) or channe (s) with the means of the invention, and so on.

 The invention therefore applies to a telescopic boom for a crane, nacelle or platform, of the type comprising a base element, and at least two movable elements, including a first movable element sliding in the base element and a second movable element sliding in the first, the first movable element being developed, in a manner known per se, by a jack mounted between the base element and itself, and the second movable element being developed, in a manner known per se, by at least one cable, chain, or the like, from a first attachment point on the base member, extending downstream, and then passing hairpin around a pulley, toothed wheel, or analogous, secured to the first movable element, and finally returning upstream to a second attachment point secured to the second movable member. According to the invention, such a telescopic arrow is characterized in that it further comprises at least one flexible pipe fixed on and along at least one of said cables, singing or the like.

 The invention also applies to a telescopic boom as defined above, but comprising at least one third movable member sliding in the second movable member. According to the invention, such a telescopic boom is characterized in that this third movable element is developed by another jack mounted between the second movable element and itself, with its rod fixed to the second movable element and its body fixed to the third element mobile, in that this other cylinder is fed via said flexible pipe, in that the body of this other cylinder is provided with at least one fluid pressure tap optionally for supplying at least one other equipment and in that said third movable element is provided with means enabling it to be immobilized with respect to the second movable element so as to immobilize said other cylinder and then use its supply fluid to supply said pressure vessel with said pressure vessel. other equipment.

 According to another characteristic of the invention, applicable to the case where the telescopic boom of the invention is used to support a nacelle or platform, a flexible pipe of sufficient strength is used to prevent by itself accidental re-entry of (or mobile element (s) developed by a device with cable (s), chatne (s) or the like.

 Finally, according to a last characteristic of the invention, applicable as above in the case where the telescopic boom of the invention is used to support a nacelle or platform, the arrow of the invention is equipped with at least one cable of security passing inside said flexible pipe, this cable being of sufficient strength to prevent accidental entry of the mobile element (s) developed (s) by a device cable (s), cat ( s) or the like.

 The invention will be better understood with the aid of the following description of two exemplary embodiments, with reference to the appended drawings in which: FIG. 1 is a diagrammatic representation of a three-element telescopic boom according to the invention; FIG. 2 is a more detailed view of the flexible and safety device fitted to the arrow of FIG. 1; FIG. 3 is a sectional view in the direction AA of FIG. 2; FIG. a diagrammatic representation of a four-element telescopic boom according to the invention; FIG. 5 is a sectional view in the direction BB of FIG. 4, all the elements being assumed to be retracted, FIG. for example, the use of the telescopic boom of FIG. 4 crane boom equipped with a variable flywheel by auxiliary hydraulic jack, - FIG. 7 represents, by way of example, the use of the telescopic boom of FIG. 4 as a personnel carrier support of the pendant type on a pivoting arm by the action of an auxiliary hydraulic cylinder; FIG. 8 represents, by way of example, the use of the telescopic boom of FIG. 4 crane crane equipped with a variable flyover by telescoping the third movable element.

 FIG. 1 shows a telescopic boom for a crane, nacelle or platform, with three elements including a base element 1 fixed longitudinally, a first movable element 2, which is slidably mounted in the base element 1, and a second movable member 3, slidably mounted in the movable member 2.

 A double-acting hydraulic jack 40, placed in the axis of the boom, has its rod fixed at the foot of the element 1, and its body fixed at the foot of the element 2. In a conventional manner and as shown schematically in the drawing, the jack 40 has its two chambers fed with hydraulic fluid via two lines 7 and 8 passing inside its rod.

 Also conventionally, a cat 9 is fixed by one of its ends at the foot of the element 1, passes around a toothed wheel 11 fixed to the downstream end of the cylinder body 40, and returns to attach at 12 at the foot of the element 3. The output of the element 2 driven by the elongation of the rod of the jack 40 then drives, in a well known manner, the proportional and synchronized output of the element -3. Also extremely classically, another cat 13, thinner, attached at 12, passing around a small gear 14 fixed to the foot of the element 2, and returning to attach 15 to the head of the element 1, allows the synchronized return of the element 3 when entering the element 2 by shortening the rod of the cylinder 40.

 According to the invention, a flexible pipe 16 of hydraulic fluid is fixed loosely, by fasteners 17, on the channe 9 all along it, ie between the points 10 and 12. This pipe 16 is connected on the one hand to a source of hydraulic fluid pressure by a pipe 18, and is connected on the other hand, by a pipe 19 passing inside the movable element 3, to a rapid uptake 20 of hydraulic fluid located at the top of the arrow as shown in the drawing.

 It is thus possible without the need to use a winder, because the flexible 16 accompanies in its movement the channe 9, a source of hydraulic pressure 20, that is to say at the head of arrow. In the absence of connection of hydraulic equipment 20, the plug is obviously automatically blocked.

 In order to serve as a safety element in the case where the arrow of FIG. 1 is intended to support a nacelle or platform of personnel, it is possible, in accordance with the invention, to use a hose 16 of sufficient strength for this purpose. . For example, one can use a reinforced rubber hose, surrounded by a strong metal braid.

 It is also possible for this purpose, as is the case in the example, to pass inside the hose 16 a cable (21, Figure 2) sufficiently relaxed and strong enough that, not participating to development efforts, it can serve as a security organ.

 Referring now to Figures 2 and 3 which show in more detail the flexible attachment of the hose 16 on the channel 9 and that of the cable 21 which passes inside said hose.

 As can be seen in these drawings, the flexible pipe 16 is fixed on the channe 9, of the multi-link type, by fasteners 17 each formed by a ferrule 23 and two gripping arms 22. The inside diameter of the ferrule 23 is very slightly greater than the outside diameter of the hose 16 so that it can slide without difficulty in this shell. This sliding is necessary for the passage of the chatne-flexible assembly 9-16 around the toothed wheel 11.

 A cable 21, slightly tensioned, passes inside the flexible pipe 16 and is fixed to the foot of the element 1 on the one hand and the foot of the element 3 on the other hand by two pieces 24 such than that shown in Figure 2.

 This piece 24, which is firmly fixed to the body of the element 1 by bolts 25, is provided with an inlet 26 for the hydraulic fluid, which communicates with a nozzle 27 receiving a piece 28 for receiving the hose 16, by its female end piece 29, and fastening and tension of the safety cable 21. As can be seen in the drawing, the end piece 29 is tightened on the piece 28 by a nut 30, so as to make the inner part of the hose 16 communicate with the inner chamber 31 of the part 28. A sleeve 32, crimped at the end of the cable 21, is supported on the end of the part 28 by means of a two-piece washer 33. The desired tension for the cable 21 is adjusted by the relative movement of the parts 34 and 35, forming between them the part 28, and which are each provided with a thread allowing this displacement. Cable 21 is not very tight because, according to the legislation, it must not participate in the development efforts of element 3.

 A particularly advantageous embodiment of the invention will now be described with reference to FIGS. 4 and 5, applied to a four-element telescopic boom, including a base element 1 and three movable elements 2, 3, 4. Figures, the reference numerals of the telescopic boom of Figure 1 have been retranscribed when referring to identical objects.

 As can be seen in the drawings, the telescopic boom of FIG. 4 is deduced from that of FIG. 1 by the addition of a third movable element 4 sliding in the element 3. In accordance with the invention, the telescopic boom of FIG. element 4 is developed by a second cylinder 41 whose body is fixed to that of the element 4 and whose rod has its end fixed at 42 at the foot of the element 3.

 To leave enough room for the jack 419, the device for developing the element 3 is, as can be seen in FIG. 5, composed of two symmetrical assemblies 93 11 flanking said jack. Two hydraulic flexible pipes 16 of the same length are loosely connected as previously to the two singing ensembles, and following the same path as the cat 9 who wears them. These two hoses 16 communicate at 12 with two pipes 43, 44, fixed in position, pass inside the rod of the cylinder 41 and bring the hydraulic pressure to the upstream chamber 45 of the cylinder 41 on the one hand and to its chamber downstream 46 on the other hand.

 In addition, two hydraulic fluid lines 47 and 48 connect the chambers 45 and 46 respectively to two fast taps 49 and 50 situated in the shape of an arrow. There is thus the possibility of supplying hydraulic fluid two complementary equipment located at the head of arrow. For this purpose, the element 4 is pierced with three holes 51, 52, 53 arranged in the longitudinal direction, and the element 3 is pierced with an orifice located near its downstream end, so as to be able, by the introduction of a pin 54, or by a latch electromagnetic control for example immobilize in relative position the elements 3 and 4, and thus the cylinder ol.

The supply lines of the auxiliary equipment can Other then connected to the fast plugs 49 and 50, which are, as is also the case for the socket 20 of Figure 1, normally closed in the absence of connection.

 Advantageously, so as to use the same two sources of hydraulic fluid to telescope in one direction or the other the cylinder 40 and the cylinder 41, the lines 7,8 on the one hand and the two lines 18 on the other hand are connected to two sources of hydraulic fluid, not shown, by means of a switching solenoid valve 55 allowing, under control of a lever 56, to act either on the cylinder 40> or on the cylinder 41. On can thus develop separately, and in any order, the elements 2 and 3, or the element 4.

 Figures 6 and 7 show among other things, two examples of application of a telescopic boom with three or four linventioa elements, equipped with a complementary equipment at the head of arrows this equipment being driven by a double-acting hydraulic cylinder. the examples are matted, it is a telescopic arrow with four elements according to Figure 4, the last element 4 having been first taken out, then stitched at 54 on the penultimate element 3 before connection of the complementary equipment on the two fast catches located at the top of the arrow. It goes without saying that a telescopic boom with three elements according to Figure 1 could also be used for these applications, but it would then include, for example according to the diagram of Figure 5, two devices 9, 11, 16 chain , flexible, and gearwheel, and consequently two lines 19 and two quick catches 20 at the head of arrow.

 The example of FIG. 6 relates to a tilting boom crane 57 whose flight is variable, in an extremely conventional manner, by the action of a double-acting hydraulic cylinder 58. The spinner, mounted in a conventional manner in a hinge 59 on the arrowhead, is shown on the drawing in three working positions, one in full lines, and two others in phantom.

 The example of FIG. 7 relates to a personnel pod 60 suspended, in a conventional manner, on a pivoting arm 61 arranged at the top of the boom and whose position in space is controlled by a double-acting jack 62. Here again, the jack 62 is fed by two hoses connected to the two quick taps such as 49 and 50> FIG. 4, located at the head of the boom, the last element 4 having been previously taken out, then stitched at 54. In FIG. the nacelle 60 and its pivoting support arm 61 are shown in two of their working positions.

 FIG. 8 represents an example, interesting for its flexibility, of using the four-element boom of FIG. 4 in a crane boom equipped with an inclinable jib 63, articulated in 64 at the head of the boom, and equipped in a conventional manner, a tie rod 65 connecting, via the two punches 66 and 67, its downstream end to the foot of the third element 3. By telescoping in one direction or the other the element 4 relative to Element 3, the flight of the dart is varied as shown in the drawing where it has been shown in two working positions, one in solid lines and the other in dashed lines. The fact that the element 4 is telescopable separately from the other three elements allows both an adjustment of the inclination of the arrow on the one hand and a setting of its working height on the other hand.

Claims (5)

 Telescopic boom for crane, nacelle or platform of the type comprising a base element (1) and at least two movable elements (2,3) including a first movable element sliding in the base element and a second movable element sliding in the first, the first movable element being developed, in a manner known per se, by a jack (40) mounted between said base element and said first movable element, and the second movable element being developed, in a manner known per se, by means of at least one cable, cat (9) or the like, from a first point of attachment (10) on the base member, extending downstream, then passing hairpin around a pulley, toothed wheel (11), or the like, secured to the first movable element, and finally returning to the upstream to a second attachment point (12) integral with the second movable element, characterized in that it further comprises at least one flexible pipe (16) attached to and along at least one of said cable, chain, or the like.  2. telescopic boom according to claim 1, characterized in that said flexible pipe is connected to a socket (20) located at the head of arrow.  3. telescopic boom according to claim 1, of the type comprising at least a third movable element (4) sliding in said second movable element, characterized in that the third movable element is developed by another cylinder (41) mounted between the second and third movable element, with its rod fixed to the second movable element and its body fixed to the third movable element, in that this other cylinder is fed via said flexible pipe, in that the body of said other cylinder is connected to the at least one fluid pressure tap (49, 50) located at the boom head and optionally for supplying at least one other equipment, and in that said third movable element is provided with means (51 to 54) for immobilize with respect to the second movable element so as to immobilize said other cylinder and then use its supply fluid to feed, by said pressure tap, said aut re equipment.  4. telescopic boom according to any one of claims 1 to 3, for supporting a nacelle or platform, characterized in that said flexible pipe is of sufficient strength to prevent by itself accidental entry of (or) the element ( s) mobile (s) developed by a cable device (s), chatne (s), or the like.  5. telescopic boom according to any one of claims 1 to 4, for supporting a nacelle or platform, characterized in that it is provided with at least one safety cable (21) passing inside said pipe flexible, this cable being of sufficient strength to prevent inadvertent entry of (or) mobile element (s) developed (s) by a cable device (s) or the like.