FI125645B2 - Telescopic boom assembly - Google Patents

Abstract

A telescopic boom assembly (15c) having at least two boom parts (20, 21), comprising an outer boom part (20), and an inner boom part (21) which is longitudinally movable inside the outer boom part (20). The outer wall structure (21c) of the inner boom part and the inner wall structure (20c) of the outer boom part define a channel (30) between them which extends longitudinally inside the boom assembly (15c). The channel (30) has a flexible energy transfer chain (24), inside which hoses, cables or the like are placed and which can be folded over itself and folded open when the inner boom part (21) moves inside the outer boom part (20). The boom assembly also has at least one support (22) which moves with the inner end (21a) of the inner boom part and supports the inner wall structure (20c) against the inner end (21a) of the inner boom part. The telescopic boom assembly (15c) can be placed on an articulated lifting boom or on a mobile work machine, especially a forestry machine.

Description

TELESCOPIC BOOM ASSEMBLY

Field of invention

The invention is directed to a telescopic boom assembly with at least two boom parts. The invention is also directed to an articulated lifting boom.

The invention is also directed to a mobile work machine with an articulated lifting boom, especially a forest work machine.

Background of the invention

Various boom systems are known to be in use, which comprise a boom assembly that is telescopic and has boom parts that move relative to each other. Flexible hoses or cables are used to conduct hydraulic or electrical energy from one boom part to another, e.g. from a stationary boom part to a moving boom part. Boom assemblies are used by different articulated lifting booms, which are placed in e.g. different work machines. One example of a work machine is a forest work machine with an articulated lifting boom.

To carry out wood harvesting, there are forestry machines that move in the terrain, such as harvesters or loader tractors.

The forestry machine has equipment attached to its boom system for handling tree trunks, e.g. a harvester head, which is only intended for cutting and felling a tree trunk growing upright, in which case it is a so-called felling head, or harvester head, which is intended for vertical = cutting, felling, pruning and

N for sawing into parts of the desired length. Equipment is also known which 3 collects energy wood or clears trees or bushes and is attached

N 30 for the boom system of a forest machine or other work machine moving in terrain. z The sawn tree trunks are collected by another well-known off-road c forestry machine, such as a loader tractor. The truck has it

N is attached to the boom system with a grapple for loading and the tree trunks 3 are transported in its cargo space. & 35

The harvester head, grapple and other equipment are attached to the end of the forestry machine — the boom system — by means of joints, for example. — Forestry machine — moves independently — on terrain = with the help of wheels or tracks =. Both the boom system and the equipment attached to it have actuators, e.g. cylinders and motors, as well as electrically controlled elements, such as valves, to which hydraulic or electrical energy is transferred, e.g. by means of flexible hoses or cables, and possibly also by means of rigid pipes.

Hydraulic or electrical energy is produced in the equipment in the frame of the forestry machine, and the boom system is also attached to the frame.

According to known technology, the hoses or cables are attached to the boom system of the working machine. Often, the boom system comprises a boom assembly that is telescopic and has relative moving boom parts.

Flexible hoses or cables are used to conduct hydraulic or electrical energy from one boom part to another, e.g. from a stationary boom part to a moving boom part. The hoses and/or cables can at least partially be placed inside the telescopic boom assembly, as for example in publication US-5718345 or EP-1507735-B1, which also utilize the energy transmission chain.

Summary of the Invention

A telescopic boom assembly according to the invention, which has at least two boom parts, is presented in patent claim 1.

In the present solution, the hoses and/or cables intended for the transmission of hydraulic energy and/or electrical energy are at least partially placed inside the telescopic boom assembly, where they are protected. 0

N The articulated lifting boom and boom assembly of the forestry machine often move 3 very close to growing trees and their branches or near tree trunks that

N 30 is processed with tools attached to the boom assembly. When hoses or cables

I is placed inside the boom assembly for protection, the risk of the hose or cable c breaking is greatly reduced.

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O The presented solution concerns a telescopic boom assembly, where

N 35 has at least two boom parts, including an outer boom part and an inner boom part.

The inner boom part can be moved longitudinally inside the outer boom part.

The inner boom section has an outer wall structure and the outer boom section has an inner wall structure opposite the outer wall structure. The outer wall structure and the inner wall structure define a channel between them that extends longitudinally within the boom assembly.

The aforementioned boom assembly also comprises a flexible energy transmission chain, inside which hoses, cables or the like are placed. The energy transfer chain moves and it can be folded over itself and folded open when the inner boom part moves inside the outer boom part.

The energy transfer chain has a first section that moves with the inner end of the inner boom section and is followed by a curved second section, which in turn is followed by a third section that is in the aforementioned channel and extends longitudinally within the boom assembly.

The aforementioned boom assembly also has one or more supports that move with the inner end of the inner boom part and support the inner wall structure against the inner end of the inner boom part. The support is located laterally in relation to the energy transfer chain and, in addition, the support in question defines one or more openings through which the third part of the energy transfer chain passes when the inner boom part moves inside the outer boom part. In one example, the opening in question is also bounded by the inner wall structure of the outer boom part. There can be two openings, located on both sides of the support.

Energy transmission chain = supports and protects hoses and/or cables.

The energy transfer chain controls the position of the hose or cable, e.g. keeping it curved, and prevents its uncontrolled transverse movement, e.g. when the boom assembly moves sideways and stops. Energy transfer chains = there can be several in parallel, e.g. two.

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3 According to one example, the energy transfer chain "consists of — several

N of 30 consecutive links, which are hingedly attached to each other like a chain. x Hoses or cables pass through the links from one link to another.

N According to one example, the boom assembly also has a guide which 3 laterally supports the third section of the energy transmission chain. The controller is

N 35 located in the aforementioned channel and extends longitudinally inside the boom assembly. The controller controls the position of the energy transmission chain and supports it, e.g. when the boom assembly moves sideways and stops.

According to one example, the guide is = releasably attached to the inner wall structure of the outer boom part. In addition, it can be the case that the guide can be installed inside the outer boom part so that the guide is slid through the inner end or the outer end of the outer boom part. The controller consists of one or several adjacent parts, e.g. two separate walls, between which the energy transmission chain is placed. The controller consists of one or several successive, longitudinal parts. For example, two energy transfer chains can be placed side by side in one controller.

A separate guide is easy to install and manufacturing the wall structure of the boom assembly is easier compared to the situation where the guide is made as a fixed part of the wall structure.

According to one example, at least two of the above-mentioned supports and in this case the above-mentioned opening is located between the two supports. Two supports delimit the gap in question between them. In one example, the controller also passes through the opening.

According to one example, the support rolls along the interior wall structure.

The support is e.g. a roller, wheel, disc or similar. According to another example, the support slides along the interior wall structure. The support is e.g. a leg, pin, stem, strip, flange, plate or similar.

According to one example, there is attached to the inner wall structure = at least one element along which the aforementioned support rolls or slides, and in addition

N the element in question extends longitudinally within the boom assembly. 3 The element in question can be a sliding bearing, which is e.g. a sliding plate or a PTFE plate.

No. 30

I According to one example, the boom assembly also has a support frame, which o is attached to the inner end of the inner boom part and moves the inner boom part

N included. The first part of the energy transfer chain is € attached to 3 support frames and in addition the aforementioned support, or several supports, is attached

N 35 — for one side of the support frame.

The support frame enables easy installation of different parts and strengthens the structure of the inner boom part. Through the support frame, the different parts are attached to the inner boom part, the structure of which can be considered simple. = According to one example, the support frame surrounds the inner end of the inner boom part, 5 so the support frame protects the inner boom part and different parts can be attached to all sides of the inner boom part with the help of the support frame. According to one example, at least one slide bearing is attached to the support frame. The sliding bearing supports the inner wall structure in the lateral direction — against the inner end of the inner boom part.

The presented solution can be applied in various articulated lifting booms, which are placed in e.g. various mobile work machines and trailers that are pulled by mobile work machines. The telescopic boom assembly according to the presented solution can be attached to another boom assembly.

An additional boom part can be located inside the inner boom part, for example, which moves inside the inner boom part. In connection with the inner boom part and the additional boom part, the principles of the solution presented above can be applied. The outer boom part can e.g. be located inside the additional boom part and the outer boom part moves inside the additional boom part.

In connection with the outer boom part and the additional boom part, the principles of the solution presented above can be applied.

The presented solution can be applied in various mobile work machines with an articulated lifting boom in which the telescopic boom assembly according to the presented solution is placed. This is e.g. independently on the ground = mobile work machines. As an example, especially forestry machines,

N like a loader and a harvester.

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N 30 The presented solution can also be applied in various mobile work machines,

I in which the telescopic boom assembly according to the presented solution is placed either directly or through another boom assembly.

N The work machines in question can have an articulated lifting boom, in which the telescopic boom assembly according to the presented solution 3 is placed. It's about

N 35, for example, different types of lifting devices, telescopic cranes and reach trucks, and where a tool, such as a fork or a work basket, is attached to the boom assembly.

A brief explanation of the drawings

In order to understand the presented solution, the explanation refers to the following pictures, which show some examples according to the solution.

Figure 1 shows a work machine according to known technology, which is especially a forest work machine with an articulated lifting boom to which a telescopic boom assembly according to the presented solution can be connected.

Figure 2 shows a telescopic boom assembly according to one of the presented solutions, which is partially transparent in the figure for illustrative purposes.

Figure 3 shows one end of the telescopic boom assembly according to Figure 2 in more detail.

Figure 4 shows in more detail the energy transmission chain and support frame of the telescopic boom assembly according to Figure 2, as well as one end of the inner boom part.

Figure 5 shows, viewed from the side and as a longitudinal section, the telescopic boom assembly according to Figure 2, which also has a guide and a sliding bearing.

Figure 6 shows in more detail one end of the telescopic = boom assembly according to Figure 2, which also has a guide according to Figure 5 and

N sliding bearing.

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N 30 More detailed explanation of the embodiments of the invention = c Figure 1 shows an example of a work machine and a lifting boom, where

The solution presented in this report can be applied. It is 3 in particular the forestry machine 10, where the presented solution can be applied

Telescopic boom assembly according to N 35.

The forest machine has a frame, which consists of one frame part or two frame parts 11a-11b, which are attached to each other by means of a joint 12.

Driving direction is controlled either by means of wheels or tracks, or by means of joint 12, as shown in figure 1. The forest machine 10 is particularly suitable for moving in variable terrain. The forest machine has a cab 13 and a power source 14, e.g. an internal combustion engine, as well as an articulated lifting boom 15 for working, attached e.g. to a frame part.

In the example of Figure 1, the lifting boom 15 is attached to the body part 11b, but it can be placed in the body part 11a, or even on top of the cabin.

The lifting boom 15 can be turned sideways and typically has several boom assemblies 15a-15c, which are attached to each other by means of joints and fasteners 19. The position of the lifting boom 15 and its boom assemblies 15a-15c is controlled with the help of actuators in order to achieve the lifting and lowering movements of the tool 16. The actuator is typically a cylinder that utilizes hydraulic energy, which is transmitted to the actuator by e.g. flexible hoses. The equipment needed to produce hydraulic energy is placed, for example, in a frame part. Typically, one boom assembly is telescoping, such as outermost boom assembly 15c.

At the end of the lifting boom 15, i.e. at the end of the telescopic boom assembly 15c, a tool 16 for working is attached by means of a bracket 18. The tool 16 utilizes hydraulic and/or electrical energy, which is transmitted to the tool by e.g. flexible hoses or cables. The equipment needed to produce electrical energy is placed, for example, in a body part. = Tool 16 can be, for example, a harvester head, for processing a tree trunk

Equipment intended for N, a grapple or equipment intended for the collection of energy wood, or 3 for example equipment intended for clearing trees or bushes, which is

N 30 equipped with saw or cutting blades. It can also be a tool that

I is a combination of the above equipment, e.g. c harvester head equipped with clearing equipment.

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O Instead of the boom assembly 15c in Figure 1, the presented solution can be applied

Telescopic boom assembly according to N 35, which is referred to in figures 2-6 with reference number 15c.

Figures 2-6 show the telescopic boom assembly 15c, which applies several different features of the presented solution simultaneously and in combination.

The features in question can be applied in the telescopic boom assembly 15c also alone or independently of each other.

The forest machine in Figure 1 is especially a loader tractor, so a loading space 17 for tree trunks is also placed on top of the body part 11b. The cargo space 17 has, for example, benches equipped with columns. The tool 16 is a grapple for handling wood. With the help of the lifting boom 15 and the tool 16, the timber is loaded into the loading space 17 or lifted out of it.

Figure 2 shows a telescopic boom assembly 15c that applies the presented solution. The boom assembly 15c comprises an outer boom part 20 and an inner boom part 21, which relative to each other are movable in the longitudinal direction. The inner boom part 21 moves inside the outer boom part 20.

The outer boom part 20 can be attached to the articulated lifting boom with the help of joints and fasteners 19.

The cross-section of the outer boom part 20 and the inner boom part 21 resembles a square or a rectangle. According to one example, the cross-section is circular or diamond-like. The inner end 21a of the inner boom part moves inside the outer boom part 20, between the inner end 20a and the outer end 20b of the outer boom part. The outer end 21b of the inner boom part moves freely outside the outer end 20b of the outer boom part. The longitudinal movement of the inner boom part 21 in and out takes place through the outer end 20b of the outer boom part. ©

N In the boom assembly 15c, a flexible energy transmission chain 24 is applied, which 3 is for hoses, cables or the like. Hoses and/or cables are placed

N 30 into the energy transmission chain 24, which protects or guides the hoses or cables

I their position. The energy transfer chain 24 is connected between parts c that move relative to each other, e.g. the inner boom part 21 and the outer boom part

between N 20, and between which hoses or cables are also connected. ©

According to one example, the energy transfer chain 24 is formed by several consecutive links that are hingedly attached to each other like a chain and so that the energy transfer chain 24 can be folded over itself as well as unfolded when the aforementioned parts move relative to each other. Hoses or cables pass through the links from one link to another. The power transmission chain 24 holds the hoses or cables within the power transmission chain 24 during movements of the boom assembly 15c. The energy transfer chain 24 is e.g. square or rectangular in cross-section, and made of e.g. plastic.

It is most suitable that the links of the energy transfer chain 24 have, for example, parts that surround hoses or cables and hold them inside the links.

The energy transmission chain 24 is connected to the boom assembly 15c so that the first section 24a moves with the inner boom section 21.

The energy transmission chain 24 is folded so that the first section 24a is extended by a curved second section 24b, the position of which depends on the position of the inner boom section 21. As an extension of the second section 24b, there is a third section 24c, which extends in the longitudinal direction of the boom assembly 15c and continues between the inner boom part 21 and the outer boom part 20, e.g. in the area between the inner end 21a of the inner boom part and the outer end 20b of the outer boom part.

Hoses or cables arrive between the inner boom part 21 and the outer boom part 20 and proceed to the third section 24c and further through the second section 24b to the first section 24a, from where they exit inside the inner boom part 21.

The inner boom part 21 has an outer wall structure 21c and the outer boom part 20 has an inner wall structure 20c opposite the outer wall structure 21c. The outer wall structure 21c and the inner wall structure 20c define a channel 30 between them which extends longitudinally within the boom assembly 15c. The third part 24c of the energy transfer chain 24 is located in channel 30. = Channel 30 is e.g. square or rectangular in cross-section

N reminiscent.

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N 30 Inner wall structure 20c or outer wall structure 21c is most suitable

I plate-like wall, which, according to one example, consists of one plate layer c in a predetermined area. That predetermined area

N is placed at the position 22 of a single support, or at the position 22 of all supports when there are at least two supports 3 22, and if necessary also in the area between the supports 22.

N 35 The predetermined area in question can also be located at 24 of the energy transmission chain. According to one example, the energy transfer chain 24, or its lower surface, and the element 50, against which the support 22 rests, are located on top of a plate-like wall that forms a uniform flat surface in a predetermined area, where the energy transfer chain 24, one or more elements 50 and the supports 22 are located. Consequently, the supports 22 extend past the upper surface of the energy transfer chain 24 towards the aforementioned flat surface and against the element 50. The guide 51 can be positioned between the energy transfer chain 24 and the plate-like wall.

In the boom assembly 15c, a support 22 is applied, of which there is at least one and which is connected to the boom assembly 15c so that the support 22 moves with the inner end 21a of the inner boom part. The support 22 rests on the inner wall structure 20c, on which the inner end 21a of the inner boom part rests via the support 22. Each support 22 consists of one part or several consecutive parts, which are located in the area of the inner end 21a of the inner boom part.

According to one example, the support 22 is located laterally in relation to the energy transfer chain 24 or the longitudinal direction of the inner boom part 21. The support 22 defines one or more openings 40, through which the energy transmission chain 24 and especially its third section 24c passes when the inner boom part 21 moves. It is most suitable that the opening 40 is also bordered by the outer boom part 20 or its inner wall structure 20c. It can also be the case that an opening 40 is formed on both sides of the support 22 and two adjacent energy transfer chains 24 are used, which work in the same way.

In another example, which is shown in Figures 2-6, there are at least two supports 22 and the opening 40 is located between the supports 22. The opening 40 is therefore bordered by two = supports 22, which are positioned laterally in relation to the energy transfer chain

N 24 or 21 of the inner boom part in the longitudinal direction. At least one 3 energy transfer chain 24 passes through the opening, or e.g. two adjacent energy transfer chains 24,

N 30 which work in the same way. = c According to one example, the support 22 is configured to roll from the inside

N along the wall structure 20c. The support 22 is, for example, a roller, a wheel, a disc or the like. 3 In another example shown in Figures 2-6, the support 22 is

N 35 configured to slide along the inner wall structure 20c. The support 22 is, for example, a leg, pin, stem, strip, flange or the like.

It is most suitable that at least one element 50 along which the support 22 rolls or slides is attached to the inner wall structure 20c.

The element 50 extends — longitudinally inside the boom assembly 15c or the outer boom part 20 and continues, e.g., to the outermost end 20b of the outer boom part 20. The length of the element 50 is at least equivalent to the travel distance of the support 22. The element 50 consists of one part or several parts located in a row, for example a strip or strip. The element 50 is, for example, a sliding bearing, which is a sliding plate or a PTFE plate (engl polytetrafluoroethylene) with low sliding friction. There are two elements 50 in the example of figures 5-6, located on both sides of the energy transfer chain 24 and placed under the two movable supports 22.

The support 22 is attached to the inner boom part 20 either directly or via the support frame 23. The support frame 23 is attached to the inner boom part 21 or its inner end 21a so that the support frame 23 moves with the inner end 21a of the inner boom part. The support 22 is attached to one side of the support frame 23, e.g. so that it forms an extension to one of the sides of the support frame 23.

In Figure 4, the support 22 is an extension of the vertical side 23c of the support body 23.

The first part 24a of the energy transmission chain 24 is attached to the inner boom part 20 either directly or via the support frame 23.

The support frame 23 according to Figures 2-6 is constructed e.g. ring-shaped or circumferential so that the support frame 23 surrounds the inner boom part 21 or the inner end 21a of the inner boom part. If necessary, one or more slide bearings 41-42 are attached to the support frame 23 and its sides 23b-23c, which support the inner boom part 21 or the inner end 21a of the inner boom part = the outer boom part 20 or the inner wall structure 20c. Support is happening

N in the lateral direction in relation to the longitudinal direction of the inner boom part 21. The sliding bearing is 3, e.g. sliding plate or PTFE plate.

No. 30

I According to Figure 4, side 23a is located next to channel 30. Side 23b c is located on the opposite side of support frame 23 and side 23c is located on side 23a

N and/or next to page 23b. The channel 30 is located between the side 23a and the inner 3 wall structure 20c. & 35

At least one element 52 is attached to the outer end 20b of the outer boom part, against which the inner boom part 21 is supported. The element 52 rolls or slides along the inner boom part 21 when the inner boom part 21 moves inside the outer boom part 20. The most suitable element 52 is placed below the inner boom part 21, if necessary also on the sides and on top of it.

A guide 51 is located inside the outer boom part 20, which laterally supports the energy transfer chain 24 and especially its third part 24c.

The guide 51 is located in the channel 30 and the guide 51 extends longitudinally inside the boom assembly 15c or the outer boom part 20. The controller 51 prevents the energy transmission chain 24 from settling in front of the support 22 and collisions. The guide 51 passes through the opening 40 and continues, e.g., to the outermost end 20b of the outer boom part 20. The controller 51 consists of one part or several parts arranged in a row.

The guide 51 is U-shaped, like a trough, which comprises walls or a pair of separate walls, between which a control channel is formed, under the protection of which the third part 24c of the energy transfer chain 24 is placed when the energy transfer chain 24 is folded open. The inner wall structure 20c can form at least part of the base of the guide 51, against which the energy transfer chain 24 is positioned. The walls of the guide 51 can be L-shaped, which are placed opposite each other, e.g. in the shape of a trough, and against which the energy transfer chain 24 is placed. The walls of the guide 51 can be |-shaped, which are placed opposite each other and are parallel.

For installation, the guide 51 is releasably attached to the inner wall structure 20c. Most conveniently, the guide 51 can be installed inside the outer boom part 20 by sliding it into the outer boom part 20 through the inner end 20a or the outer end 20b of the outer boom part. It is most suitable that the guide 51 is a U-shaped trough.

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3 The protective housing 25 is attached to the inner end 20a of the outer boom part.

N 30 Inside the protective casing 25 is a space into which the energy transmission chain is curved

The second part 24b can be moved when the inner boom part 21 moves c inside the outer boom part 20 and the inner end 21a of the inner boom part moves towards

N the inner end of the outer boom part 20a. The housing 25 is an extension of the outer boom part 20 3 and there is access to its interior through the inner end 20a of the outer boom part. & 35

The invention is not exclusively limited to the examples, embodiments and alternatives shown in the figures or above, and should not be used as limiting alternatives. As an example, let us mention that the channel 30, the third part of the energy transfer chain 24c, the guide 51 or the supports 22 can also be located on top of the inner boom part 21 or on the sides. when the boom assembly 15c is viewed horizontally as shown in Figure 2. In this case, the supports 22 are directed upwards, for example, and the U-shape is open downwards. Most suitably, the channel 30, the third part of the energy transfer chain 24c, the guide 51 or the supports 22 are located under the inner boom part 21 as shown in figure 2. In this case, the supports 22 are directed downwards and the U-shape is open upwards.

The images shown above should also not be taken to mean that all the features shown in them are also used in the presented solutions. The features presented above can be combined in a telescopic boom assembly so that it has the desired functions. The support frame 23 is not necessary, but it facilitates the installation. The controller 51 is not necessary, but it prevents lateral oscillations of the energy transfer chain 24.

The invention can be applied to the extent defined in the attached patent claims. 0

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Claims (13)

Patent Claims 1. A telescopic boom assembly (15c) with at least two boom parts (20, 21), comprising: - an outer boom part (20), and - an inner boom part (21) which is — movable — longitudinally inside the outer boom part (20), - the outer wall structure (210) of the inner boom part ), - an inner wall structure (20c) of the outer boom part opposite the outer wall structure (21c), wherein the outer wall structure (21c) and the inner wall structure (20c) define between them a channel (30) extending longitudinally within the boom assembly (15c), and - a flexible energy transfer chain (24), inside which hoses, cables or the like are placed and which can be folded over itself and folded open when the inner boom part (21) moves inside the outer boom part (20), and has a first section (24a) which moves in the inner part of the inner boom part along with the head (21a) and followed by a curved second section (24b), followed by a third section (24c), which is in said channel (30) and extends longitudinally inside the boom assembly (15c), characterized in that the boom assembly additionally comprises: - at least one a support (22) which moves with the inner end (21a) of the inner boom part and supports the inner wall structure (20c) against the inner end (21a) of the inner boom part, and in addition said at least one support (22) is located laterally in relation to the energy transfer chain (24), and in addition said at least one support (22) defines one or more openings (40), through which the third part of the energy transfer chain (24c) passes N when the inner boom part (21) moves inside the outer boom part (20); N - and where at least > one element (50) is attached to the inner wall structure (20c), which is a PTFE sheet acting as a sliding bearing and along which at least one of the supports (22) mentioned N 30 slides and which extends x longitudinally inside the boom assembly (15c). O N 2. Telescopic boom assembly according to claim 1, 3 characterized in that the boom assembly comprises said supports (22) at least N 35 — two, and furthermore said one or more openings (40) are located between said at least two supports (22). 3. A telescopic boom assembly according to one of claims 1 to 2, characterized in that the telescopic boom assembly additionally comprises a support frame (23) which is attached to the inner boom part (21) and moves with the inner boom part (21), and to which the first part (24a) of the energy transfer chain (24) is attached, and in addition to one side of which the relevant support (22) is attached. 4. A telescopic boom assembly according to claim 3, characterized in that the support frame (23) is adapted to surround the inner end (21a) of the inner boom part. 5. Telescopic boom assembly according to claim 3 or 4, characterized in that at least one slide bearing (41, 42) is attached to the support frame (23, and which slide bearing (41, 42) supports laterally — against the inner end (21a) of the inner boom part the inner wall structure (20c ). 6. A telescopic boom assembly according to one of claims 1 - 5, characterized in that the telescopic boom assembly - further comprises at least one element (52) which is attached to the outer end (20b) of the outer boom part and against which the inner boom part (21) is supported and configured to roll or slide when the inner boom part (21) moves inside the outer boom part (20). 7. A telescopic boom assembly according to one of claims 1 to 6, characterized in that the telescopic boom assembly N additionally comprises a protective housing (25) which is attached to the inner end (20a) of the outer boom part N and which defines the space into which the curved second part (24b) of the energy transmission chain can move when the inner boom part (21) moves inside the N 30 outer boom part (20). 7 © 8. The telescopic N boom assembly according to one of claims 1 - 7, characterized in that the telescopic boom assembly 3 additionally comprises a guide (51) which laterally supports the third section (24c) of the energy transfer chain N 35 and is located in said channel (30) and extends - longitudinally inside the boom assembly (15c). 9. A telescopic boom assembly according to claim 8, characterized in that said guide (51) passes through said opening (40). 10. A telescopic boom assembly according to claim 8 or 9, characterized in that the guide (51) is U-shaped, comprising walls or a pair of separate walls that define a control channel between them, in which the third part (24c) of the energy transfer chain is located. 11. A telescopic boom assembly according to one of claims 8 to 10, characterized in that the guide (51) is removably attached to the inner wall structure (20c) of the outer boom part, and that the guide (51) can be installed inside the outer boom part (20) by sliding it over the inner end of the outer boom part ( 20a) or through the outer end (20b). 12. Articulated lifting boom, characterized in that the articulated lifting boom comprises a telescopic boom assembly according to claims 1 to 11 >a3/. 13. A mobile work machine, especially a forestry machine, with an articulated lifting boom, — characterized in that the articulated lifting boom comprises a telescopic boom assembly according to one of claims 1 to 11. < N O N O N O I = O N N LO O O N L