DE2312928A1 - TELESCOPIC BOOM FOR A CRANE - Google Patents

Description

23 550

Fulton Industries, Inc.

Telescopic boom for a crane

The invention relates to a boom for a crane with a first section and a second telescopic section in the first captured section and a third telescopically in the second captured section. The invention thus relates in particular to telescopic crane booms for lifting and moving loads such as, for example a person and / or equipment.

There are different types of cranes for lifting inert Loads or known from persons. Cranes, primarily used for lifting people, are common known as so-called above-ground platforms. Telescopic cranes, which have been used for both purposes, have been around for years in use and more recently the development of

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Telescopic cranes to move the various telescopically telescoping sections by means of flexible articulated members connected to two adjacent sections. Such joint organs can be ropes, wire cables or chains. Known constructions, however, prove to be quite bulky and clumsy ₇ and it is often necessary that the entire extension movement of the telescopic crane section takes place as a function of a force which is applied by a single element such as the shaft of a crank or a winch. For this purpose, very stable elements and fastening devices are required, which lead to expensive and sohweren devices which were generally too slow and bulky and could not be easily controlled. In particular, the control of cranes with a platform above the ground has so far proven to be extremely difficult.

Flexible articulated actuators for the telescopic sections have recently been replaced by fluid motors in the form of double-acting hydraulic cylinders. This replacement of the joint organs by hydraulic cylinders took place _x as soon as they had reached a stage of development in which they were sufficiently powerful and reliable and appropriate pumps and valves for control and energy supply were available. In a three-part telescopic boom, a first hydraulic cylinder was characteristically attached to move the second section relative to the first, and a second hydraulic cylinder was provided to move the third section relative to the second. In conventional designs, there were fewer hydraulic cylinders than sections by a factor of one, and corresponding control means were also provided for this.

The conventionally used control means for the hydraulic cylinders have been valves that have a medium under pressure

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led to the cylinders, a control handle or lever for controlling each cylinder was provided so that one Actuation of a handle in one direction extends the boom and retracts the same in the other caused. Independent handles or levers were provided for the control valves of each cylinder. So it was necessary that the operating personnel had to be trained that an external boom section of smaller cross-section should not be extended if the desired reach of the crane is not achieved by a previous extension an inner boom section of larger cross-section can be achieved. Experience showed, however, that despite careful training and instruction of the operating staff from time to time, be it out of clumsiness or chance, for example the third or end section of a three-part boom, during the second or middle paragraph was still fully withdrawn. Result of such a mistake possibility was that the end section was overloaded or damage to the boom occurred.

A system for avoiding such actuation of the end or third section has already been proposed and uses a complex and expensive hydraulic control system. This known system was fully extended of a cylinder is required to control the middle section before supplying medium to the end section extending cylinder took place. This solution turned out to be however, because of the complexity of the hydraulic equipment and the considerable costs involved, it is not considered full satisfactory.

Another consideration in connection with the construction of telescopic booms for cranes is the weight of the sections and the parts belonging to them, especially the hydraulic cylinders. With a three-part

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Boom, a first hydraulic cylinder was previously connected to the first and second sections for extending and retracting the same, the cylindrical part of the hydraulic cylinder being arranged in the first section. Similarly, a second hydraulic cylinder was connected to the second and third sections for extending and retracting the latter, this hydraulic cylinder being arranged in the second section. Accordingly, when the second section is extended, the second hydraulic cylinder moves outwards from the crane pivot axis, so that its weight is added to the weight of the second crane boom section with increasing distance ύ from the pivot axis. In a typical 13 * 5 m boom with three sections of essentially 4.5 m each, the hydraulic cylinder can have a weight of about 225 kg and its center of gravity is about 6.7 m from the pivot axis when the boom is in a horizontal position. As a result, the hydraulic cylinder for extending the third section contributes considerably to the weight and the momentary stress on the crane boom.

In contrast, the invention is based on the object of creating a telescopic crane boom of the type mentioned above, which have a comparatively low weight compared to known construction methods but still have the same strength target. The extension and retraction equipment should be lighter than previous construction methods. Another object of the invention is to provide a telescopic crane boom structure in the an unintentional extension of a less fixed boom distance when a boom section is still retracted should be avoided with higher strength. Further, underlying the invention objects are Creation of a telescopic crane boom in which the less rigid section is simultaneously extended and retracted should be extended and retracted higher strengthened section;

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⁵ "231292a

in which the extension and retraction of one boom section while extending and retracting the other simultaneously by means of a pair of joint organs is to be made; in which the joint organs for extending and retracting a section serve as a function of the extension and retraction of the other section and it is ensured that an impairment of the movement of the joint organs is prevented will.

The inventive solution to the stated object is characterized by a fluid motor, similar to the first and second portion is connected for linear movement of the second Absohnitts relative to the first such that the second section can be extended and retracted selectively and by a linear extension and retraction movement of the second Section moving connecting device for simultaneous linear extension and retraction of the third section.

The invention thus creates a telescopic crane boom, for example with three sections, a first one or orund section, a second or middle section and a third or end section, the base section is pivotally attached to a support member for raising and lowering the boom about a horizontal axis. The boom arms are each extendable in the longitudinal direction and point generally hollow, rectangular cross-sections. It is the cross-section of the base section is greatest and this telescopically accommodates the middle section, the in turn receives the end section. A fluid motor in the form of a double acting hydraulic cylinder is provided and connected with the basic and middle absenteeism in a known manner in such a way that the middle absenteeism is off and can be retracted. The third or end section is made by a mechanical connecting device depending on the movement of the second or middle section moves, with the kinetic energy for the final approval duroh

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applied the hydraulic system including a conventional pump for the aforementioned hydraulic cylinder will. This mechanical connecting device is designed in the form of flexible joint organs, in particular chains, a first and a second chain being provided. The second or middle section has arcuate guide surfaces equipped for engagement with the flexible joint organs, whereby essbh is specially designed for chain wheels acts, the chamber with the chain, a front or outer sprocket is near the outer end of the middle Absohnitts and is placed on the bottom plate of the middle section if this is the aforementioned generally has hollow, rectangular cross-sectional shape, carried. A rear or inner sprocket is supported by the middle section near the inner end and the axles Both sprockets are at height or below the bottom plate of the middle section. The first chain extends from one of them with the Bodinselte of the base plate the anchoring connecting the base section through an opening in this base plate, and then to the rear into the room between the floor slabs of the base section and the middle section Section. It extends around said rear sprocket, its other end with the bottom plate of the End portion is connected near the inner end. The connection is made through an anchorage and close to the anchorage there is another anchorage to which the second chain is connected. The second chain extends into the Space between the bottom plate of the middle and end section and to the front, is then over the front or outer sprocket guided and is through an anchoring to the bottom surface of the bottom plate of the base section near the first anchoring tied together. If a medium is fed to the hydraulic cylinder to extend the central section, 30 moves the outer sprocket outwards and exerts a tension on the second chain, whereby the end unit is also subject to tension and thus extends at the same time. With the reverse

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When the hydraulic cylinder is actuated, the middle section is retracted and the inner sprocket pulls on the first chain or leads to a simultaneous retraction of the end section with the middle section.

An embodiment of the invention is based on the drawing explained in more detail below. Show it

Fig. 1 is an overall view of a mobile crane with a Telescopic boom according to the invention,

FIG. 2 is an enlarged, partially sectioned longitudinal view of the boom according to FIG. 1,

3 shows an enlarged cross section along the cutting line III-III according to Fig. 2,

FIG. 4 shows an enlarged cross section along the section line IV-IV according to FIG. 2,

FIG. 5 shows an enlarged cross-section along the section line V-V according to FIG. 2, and FIG

FIG. 6 shows an enlarged cross section along the section line VI-VI according to FIG. 2.

In the drawing, the same parts are identified by the same reference numerals. In Fig. 1 the crane shows the general Reference symbol IG, this being a mobile crane or a crane attached to a vehicle with a Vehicle 11, a turntable 12 and supports 13 is. The telescopic crane boom is marked 15 and consists of a first or basic section 16, a second or middle section 17 and a third or end section 18. The outer end of the end section 18 is provided with a support nose 19 on which a basket-shaped

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Above floor platform 20 is attached. Control devices are preferably provided in the platform 20 for controlling the extension and retraction movement of the sections 17 and 18 and other control means, for example, for raising and lowering the boom 15 and rotating the whole Booms including the turntable 12 can be arranged in a known manner. As shown, can Lifting and lowering cylinders 21 and 22 can be connected to the turntable 12 and the base section 16 of the boom 15.

In Fig. 2, the telescopic boom 15 is shown in the retracted or retracted position in cross section. Thereafter, each hollow boom section of lower strength and similar hollow cross-sectional dimension is telescopically received in the next boom section of larger cross section and higher strength. The base section 16 is provided with protruding eyelets e.g. 26 for attaching a first cylinder for lifting and lowering the boom 15, while a second eyelet 27 for receiving a pivot pin, not shown, can be raised and lowered on the boom 15. A third eyelet or axle construction 28 is used for connection to a lifting cylinder, for example the lifting cylinder 21 according to FIG hydraulic lines are used, which extend from the platform 20 to the various elements to be controlled. From Fig. 2 it can be seen that the base section 16 is provided with lateral reinforcing plates 31 and 32. The cross-sectional shape of the base section is also shown in FIG. 3 and is a generally hollow rectangular cross-section with a top plate 16a, side plates 16b and 16c and a bottom plate 16d.

Within the base section 16 can be seen in FIG

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recognize middle section 17 at its inner end is provided with a sanding pad 33, which is between the Absohnitten 16 and 17 is arranged. According to Fig. 3 are two such sanding pads 33 are provided. The end section 18 is arranged within the middle section 17 and between these there is a sanding pad 34. Inside of the end section 18 is a hollow housing 35. The hollow housing 35 has on its inner side in FIG End of a flange 36 which is attached to a housing support plate, which in turn is close to the inner or rear The end of the middle section 17 is attached. The hollow housing support plate 37 has, as shown in FIG. 3, an open rectangular shape, and a plurality of bolts or screw caps are used to connect the flange 36 and the fastening plate 37. A fluid motor 40 specifically in the form of a double acting hydraulic cylinder is also in Fig. 2 and 3 shown and extends sioh through the fastening plate 37. In Fig. 3 are also other sole cushions 38 and shown, the between the Orundabsohnltt 16 and the middle Section 17 are provided.

At its rear end, the fluid motor 40 is provided with a transverse tube 41 in which a pivot pin 42 is located, which is connected to the base unit at its inner or rear end connected 1st.

The fluid motor 40 has an extensible at its outer end Rod 43 to which a tube 44 is attached. A pin 45 is received in the tube 44 and, as shown in FIG. 6, a pair support plates 46 and 47 located at a distance from one another are held. The support plates 46 and 47 are at the outer end of the hollow housing 35. When actuating the Fluidraotors 40 there is thus a linear movement of the middle section 17 relative to the base section 16 as a result of the duroh the hollow housing 35 ^ the flange 36 and the mounting plate

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~ ¹⁰ ~ 2 3 1 2 ^q ? 8th

37 created connection.

A mechanical connection system is used to simultaneously extend the end section 18 with the middle section 17 or to retract or retract the end section 18 at the same time as the middle section 17, the mentioned linear movement of the end section 18 being carried out by the mechanical connection actuating the middle section 17 will. According to FIG. 2 and \ ^l has the central portion 17 at its bottom 17 plate 173 sine opening 51 near its inner end and immediately outside or in front of the mounting plate below the opening 51 is a Kettenradbefestigungsanordnung 52 attached, which irr generally! with the bottom of the base plate γι? 1st secured in the mounting assembly 53, a sprocket 53 is mounted, the rear a pair or ί, -ηηζτε sprockets 5 ¹ carries * _s which are held in transversely spaced · in Abatanö. At its outer end, the central section l " ⁷ rr is provided with a fastening arrangement 5- which is conveniently connected to the base plate 16d _/ see FIG. 5", and in this fastening arrangement there is a sprocket shaft 57 with a Pair of spaced outer or front sprockets 58. The sprockets 54 and 56 serve as guides and, as shown, rotate about the shafts 53 and 57, the axes of which are at or below the bottom plate 17d of the central partition 17. This position of the sprocket shafts 53 and 57 is important in that it prevents interference between the chains and the fixed boom elements and thus ensures a long service life of the boom without excessive wear or tear.

The Qrundabsohnitt 16 is close, its outer end with a first anchorage 61 on the bottom surface of the bottom plate l6d Mistake. Inside to or behind the anchorage 6l, the base plate l6d has an opening 62 ^ and a pair of chains 60

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extends from the anchorage 51 through the opening 62 and then backwards into the space between the floor 16d of the base section 16 and the floor plate 17d of the central recess 17 to the sprockets 54 according to FIGS. 2 and 4. The chains 60 are on the sprockets set 54 and extending around it and then to the front is located a the bottom of the bottom plate of the Endabsohnitts l8D associated anchor 63. Immediately before the anchor 63 is a AUJ & hnliohe manner with the bottom of bottom plate l8D connected Verankerung64 _/ and with the anchor 64, a Pair of chains 65 connected. These chains 65 extend forward from the anchorage 64 into the space between the floor panels 18d and 17d and to the sprockets 58 As shown, the anchors 61 and 66 lie next to one another, the anchoring 66 being closer to the outer end of the base section than the anchoring 61.

In Ffe 5, both the aforementioned Sohleifpolster ^ k and the additional abrasive pad 38 shown. All of the sanding pads or cushions are of well known construction, and are preferably made of a suitable material to allow relative sliding movement between the various boom sections and at the same time ensure a long service life.

In operation, a pump leads a pressure medium to the fluid motor 40 through a corresponding control valve so that the latter is actuated. In the present case, the fluid motor is 40 designed in the form of a double-acting hydraulic cylinder / the distance to the pins 42 and 45 / to which the fluid motor 40 is connected increases as the piston moves and here the middle section 17 as a result of the previously

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called connection of the pin 45 with the hollow housing 35 and then with the middle section 17 or the anchoring of the pin 42 with the base section 16 extends. When the middle section 17 is extended, the chain wheels 58 move away from the base section 16. This movement of the sprockets 58 exerts a pull on the chain 65, which acts as a flexible joint member. Since one end of the chain is immovably held by the anchor 66 65 ₇ of the upper path exerts the chain 65 according to Pig. 2 exerts a force on the anchorage 64 and thus on the end section 18 _/ so that this is extended linearly and simultaneously with the linear extension movement of the central section 17. Such a simultaneous extension of the end section 18 through the middle section 17 can continue up to the limit of the physical dimensions of the devices, the full extension length of the boom I5 being determined by these dimensions. When the fluid motor is operated in the opposite direction by means of a corresponding control valve device, the forces acting on the pins 42 and 45 lead to a linear retraction of the central section 17 and thus an inward movement of the chain wheels 54 to the inner end of the base section 16. The flexible joint member formed by the chains 60 will act on it and exert a pull on the anchorage 6j5 so that the end section 18 is retracted at the same time as the middle section 17 is withdrawn.

It will be understood that during the extension of the boom sections 17 and 18, the sprockets 54 move outward from the space between the lower plates 17d and l6d to the space move between lower plates 18d and 17d, part of the chain wrapping around the sprocket. Moved the other way around During the retraction movement of the boom sections 17 and 18, some of the chains 65 move away from the bottom of the base plate l6d in the space between the floor panels I8d and 17d.

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The telescopic crane boom described here is with only provided with a single pluid motor, which allows the simultaneous extension and retraction of both the central suction 17 as well as the end section l8 accomplished. This is due to its connection with the basic section l6 and the middle section 17 and the mechanical articulation connected to the end section 18, which depends on the movement of the middle Absohnitts 17 is moved and is actuated by this. In this way became a telescopic crane boom GPS port, which sioh by extending the lighter end section with a smaller cross-section when the stronger one is nooh retracted position, Can not overload a larger cross-section having central portion. It also stands out the extendable boom described here has a lower weight because it saves a lot of weight Compared to previous boom construction methods, the actuating equipment is almost entirely given. While so far a second hydraulic cylinder with a weight of about 225 kg was required to extend the end section the weight of the mechanical linkage including the flexible joint organs in the form of chains, whose guide surfaces in the form of sprockets and the necessary anchoring equipment only about 22.5 kg.

It goes SiOH, that a skilled person can make numerous changes to the embodiment described without departing from the scope thereof is of the invention. Both the drawing and the description are therefore not to be regarded as restrictive.

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Claims (14)

Patent claim α c- h 1.) Boom for a crane with a first gate, a second telescopic in the first section and a third telescopic in the second section, characterized by a FIrid motor (40) which is connected to the first (16) and the second ·? .-! fi ") Absohnitt to the linear movement of the second Absehr.itrcs r-ilst ■ ', .-- ■ κιτπ he is connected first in such a way. That the second section is selectively extendable and retractable, and through one through dis linear extension and Entry movement of the second section moved verc device for the simultaneous linear retraction of the third section (18), 2. Aueleger according to claim 1, characterized in that the connecting device blegsarss has oil joint organs and means to connect the G ^ ienkorgar-a with the first and third paragraphs, 3. Boom according to claim 2, characterized in that k β r. η - zeiohnet that front and rear arched form, arranged by the second section at a distance from each other © Guiding means are provided _s whose axes extend transversely from the second section and guided around the joint organs s Ind. 4. Boom naoh Anspruoh 3, characterized in that first and second flexible joint members are provided, wherein the connecting device for the flexible oil joint members on first and second anchorages the first step near the outer end and third and fourth anchors on the third step near it Have inner end. 309839/0474 - 15 - 5. Boom according to claim 4, characterized in that the first and second anchorages on the lower surface of the floor of the first boom section, with an opening in the floor of the first boom section is provided behind the anchorages, and that a first hinge member extends from a first anchorage through the opening to the rear to the rear guide device and to the third anchorage. 6. Boom according to claim 5 *, characterized in that the second ^G eienkorgan extends from the second anchorage near the front to the front guide device and then to the rear to the fourth anchorage. 7. Boom according to claim 1, dadirch g e k e η η draws, that the last-mentioned device has a first connected to the first section near its outer end Having chain extending around a sprocket passing through the second Absohnitt near its inner end and which chain is connected to the third section near the inner end. 8. Boom according to claim 7 »characterized in that the device further has a second the first section has near its outer end connected chain, which is wrapped around a through the second section sprocket held at its outer end and connected to the third section near its inner end is. 9. Boom according to claim 8, characterized in that the axes of the chain wheels are lower are arranged as the bottom of the second section. 10. Boom for a crane with a first telescope-like section taken up in a second section, 309839/0474 - 16 - :; ° -2928 the second section being telescopically received in a third section. and the sections in the longitudinal direction are extendable and have cave Qjjersohnittsforms, marked J-urc-h rushed in the first and second section for extending and retracting the second section connected fluid emergency, through anterior and posterior ere through the second section near its exterior or interior End carried guide means with arcuate operative surfaces concentric to axes which are mutually exclusive extend across the boom sections and not above the bottom of the second section, through a first flexible one Articular organ, which at the first section nalis its outer end is anchored and extends around the rear guide means and is further anchored to the third section, and anchored to the first section by a second bJe gsames Articulated organ that extends around the front guide means and further anchored to the third section near the inner end thereof. 11. Boom according to claim 1Oj, characterized in that g s k e η η draw t that the guide means are formed from sprockets are, the flexible hinge members around the sprockets are laid chains, 12. Cantilever to kxiBOTi.c ':: - 10 *' ii.a r ■■ ;; -. ; -5 ■ /; e η π ~ ζ e ic h η et that the e / 'sts Abbe ·. ;; "'' ■ '', ?! ■. ·. ;;; * ■. ''" Λ _{,. C} _. At its bottom near its outer IW- Λ _α :. A -. ": - -c'z -v. ^r : ·· '. ". ^ i ^: - :: ur · ^; for anchoring dss er · σ ·"; ■? .η ■' ■■ ^ ϋ.-ό--: -χ .. ■. "■■ - ■: ■■ · ; -; ■■:: c .0 ·. Ο ·: -; fl -:"'- of the first session. ί · γ · ■ '■■ ί-ί - ι · -. '· ■; "...: ό ^-;"::: Γ'■■;:'■ * ■ ..: ■ ^.... ". that the joint organ is c- ^ ch ..;:. :: ■ ..ff:; -.,. ■ · · - ■■; -; - rear guide ^, 3niit-t ^ j - \.: λ- Ι ε -.:.:..:-.■■ ^:. ■: ··. ■ ·· ■ - · '■ "; -. ■ · -: second section ersti-eo-ΐ ;, 13. Boom draws that its bottom has that a device is provided for attaching the rear guide means to the opening and that the first, big, articulated organ revolves around the rear Guide means and duroh the opening extends. 14. Aueleger according to claim 10, characterized in that the second flexible joint member with the first partition is anchored near its outer end, and sioh around the front guide means and then backwards between the second and third branch extends to an anchorage, which on the third branch is near its interior End is attached. 309839/0474