The present invention relates to an apparatus for moving cylindrical parts, from a rack situated at the level of the lower part of the apparatus, up to the required working area and vice versa.

The cylindrical parts may be for example solid cylindrical pillars used in buildings or may be tubular pieces such as pipes.

The working area may be for example a building floor (in case of the pillars) or a rig floor (in case of the pipes).

Apparatuses for moving cylindrical parts are known in the art, such as the apparatus disclosed in WO2013/06933A1 , that comprises a footing located at the level of the pipe rack and a supporting structure mounted in a pivoting manner to the footing, thus defining a transport line for a pipe. Said apparatus further comprises an actuator, interposed between the footing and the supporting structure, for the rotation of the structure with respect to the axis of pivoting with the footing, thus raising one end of the structure. Arranged at the side portions of the structure are respective means of gripping and conveyance of at least one pipe for the transfer thereof from the level of the pipe rack to the accommodation surface of the transport line defined on the supporting structure.

The disadvantages of the apparatus disclosed in WO2013/06933A1 are:

- relative low productivity (i.e. the total necessary time for moving a pipe from the pipe rack up to the rig floor is relatively high);

- it can pick up pipes only from very high pipe racks;

- it has a wide footprint; it needs a large space between the apparatus and the pipe rack;

- it cannot lift pipes to rig floors of 10-15 meters high;

- it is not efficient for rig floors of 5-7 meters high, it needs too much space and too long travel because of the fixed length of the upper arm;

- it cannot be used for pipes of big dimensions and weights. The scope of the present invention is to solve the above-mentioned disadvantages and to add new capabilities, by providing an apparatus that is capable to carry out all the following tasks:

- to increase productivity (the necessary operating time is about 25% shorter than in the case of the apparatus of WO2013/06933A1 );

- to pick-up cylindrical parts from very low racks (0.2m), like on jack-up rigs in offshore drilling;

- to have a narrow footprint - a reduced distance between the apparatus and the rack;

- to pick-up cylindrical parts from several rows laid on the rack, with the highest row height minimum 3m;

- to deliver the cylindrical parts at working area heights of up to 15m;

- to deliver the cylindrical parts at optimal angle and position to any working area height of up to 15m;

- to have maximum efficiency for any working area height of up to 15m;

- to lift cylindrical parts of up to 30 inch of diameter, 15m of length and 6 tons of weight;

- is easy to transport (inside one truck) and is easy to assemble (less than 2 hours rig- up and rig-down).

The apparatus for moving cylindrical parts according to the invention comprises: a support body, at least two pairs of legs connected at the upper part thereof to the support body,

- the legs of each pair being situated symmetrically and on opposite sides in respect to the support body,

- each leg being provided with a movable claw mechanism for transporting the cylindrical part along the leg from a region situated at the lower part of the leg up to the upper part of the leg or vice versa, a lower arm connected at one of its ends to the support body by means of a joint, and connected at its other end to an extremity of a first actuator, wherein the other extremity of the first actuator is fixed to the support body, wherein, upon the action of the first actuator, the lower arm is capable to pivot about the joint in respect to the support body, wherein the lower arm is provided with a first drive chain arranged in an elongated loop extending along the entire length of the lower arm, - a second actuator capable to drive the first drive chain,

- a cradle situated above the lower arm and capable to receive a cylindrical part on its upper surface,

- a shoe that can be releasably fixed in several positions along the upper surface of the cradle,

- a second drive chain arranged in an elongated loop and mounted in a frame between the lower arm and the cradle, said second drive chain having a first chain link fixed to the lower arm by means of a first connection element, said frame being connected to the first drive chain by means of a second connection element, said second drive chain having a second chain link, opposed to the first chain link, fixed to the cradle by means of a third connection element,

- wherein, upon driving the first drive chain by the second actuator, the second drive chain together with its frame and with the second connection element is capable to move relative to both the first drive chain and the lower arm, between a first extreme position and a second extreme position, while at the same time the cradle together with the third connection element is capable to move relative to the first and second drive chains and relative to the lower arm, between a first cradle extreme position and a second cradle extreme position.

In a preferred embodiment of the apparatus according to the invention, the claw mechanism comprises:

- a claw for grabbing a cylindrical part,

- a first pair of bearings fixed to the claw and capable to roll along a pair of straight paths provided along the length of the leg,

- an individual bearing or a second pair of bearings fixed to the claw and capable to roll along a different, individual inclined path provided along the length of the leg,

- a third actuator capable to move, by means of a lifting element, the claw from the lower part of the leg up to the upper part of the leg or vice versa,

- wherein the claw, all the bearings and all the paths are located in respect to each other such that, when the claw is situated at the upper part of the leg, it is in a position rotated approximately 60° in respect to the plane of the individual path in comparison to the position of the claw when situated at the lower part of the leg. In a preferred embodiment of the apparatus according to the invention, each leg is telescopic and comprises a fixed upper leg member and a mobile lower leg member, the fixed upper leg member being connected to the support body, the apparatus further comprising a third actuator capable to move, by means of a first lifting element, the mobile leg member from a protracted position in which the mobile lower leg member is in extension of the fixed upper leg member and almost completely outside the fixed upper leg member, to a retracted position in which the mobile lower leg member is almost completely accommodated within the fixed upper leg member, and vice versa, and wherein the claw mechanism comprises:

- a claw for grabbing a cylindrical part,

- a first pair of bearings fixed to the claw and capable to roll along a pair of straight paths provided along the length of the mobile lower leg member,

- an individual bearing or a second pair of bearings fixed to the claw and capable to roll along a different individual inclined path provided along the length of the mobile lower leg member surface,

- a second lifting element fixed at one extremity to the claw and fixed at its other extremity to the lower part of the fixed upper leg member,

- wherein upon activating the third actuator, the mobile lower leg member moves relative to the fixed upper leg member, while at the same time the claw moves between the lower part of the mobile lower leg member to the upper part of the lower leg member,

- wherein the claw, all the bearings and all the paths are located in respect to each other such that, when the claw is situated at the upper part of the lower leg member and at the same time the lower leg member is in the retracted position, said claw is in a position rotated approximately 60° in respect to the plane of the individual path in comparison to the position of the claw when situated at the lower part of the lower leg member while the lower leg member is in the protracted position.

In a preferred embodiment of the invention, the apparatus further comprises a cam hinged at the upper part of each leg such that when the claw is in a position at the upper part of the leg, a part of the claw mechanism pushes the cam and tilts it about the hinge, such that a surface of the cam and a surface of the claw define together a continuous inclined rolling surface for the cylindrical part. In a preferred embodiment of the invention, the apparatus is provided with one upper arm connected to the lower arm and capable to adopt a position in extension to the lower arm.

In a preferred embodiment of the invention, the apparatus further comprises a second upper arm or both a second upper arm and a third upper arm, wherein all the upper arms are capable to adopt a position one in extension of the other, either in a telescopic or in a modular manner.

In a preferred embodiment of the invention, the apparatus further comprises a back extension element fixed at the end of the lower arm that is situated closest to the joint.

In a preferred embodiment of the invention, the apparatus is provided with two pairs of legs, and at least one of the two pair of legs is movable along the support body.

In a preferred embodiment of the invention, the pairs of legs are spaced one in respect to the other such that the corresponding claw mechanisms are capable to lift a cylindrical part having a length between 5 m and 15 m.

In a preferred embodiment of the invention, upon the action of the first actuator, the lower arm is capable to pivot about the joint in respect to the support body by an angle between 0° and 32°.

In a preferred embodiment of the invention, all the legs are articulated to the support body such that each leg is capable to adopt a position in which its length is arranged approximately along the length of the support body.

According to another aspect, the present invention refers to a method of moving cylindrical parts, comprising the following steps:

- providing an apparatus according to the invention;

- providing cylindrical parts arranged in several rows on a rack, wherein the top row height is at least 3m; - fixing, to at least two legs situated on the same side of the support body facing the rack, an extremity of a respective transfer arm;

- inserting an end region of each respective transfer arm under the top row of cylindrical parts, said end region of the transfer arm being opposed to and at a higher level than said extremity of the transfer arm that is fixed to the leg, the slope of each transfer arm being about 2 to 3 degrees;

- rolling a cylindrical part, from the rack, on the rolling paths defined by said at least two transfer arms until it contacts the respective legs;

- grabbing, by means of the claws associated to the respective legs, the cylindrical part and lifting the cylindrical part until the upper part of each leg in a position from where the cylindrical part rolls, under its own weight, on the cradle.

The following non-limiting embodiments of an apparatus according to the invention relate to figures 1-12, representing:

Fig.1a, Fig.1b: apparatus according to the invention, in the rest position;

Fig.2a, Fig.2b: sequence of three different positions of the lower arm of the apparatus from figures 1a and 1b;

Fig.3a, Fig.3b: lateral view of a sequence of three different positions of the lower arm of the apparatus from figure 1 a and 1 b;

Fig.4: position of the lower arm and of the cradle of the apparatus from figure 1a with details of the connection points;

Fig.5a: sequence of three different positions of the ensemble formed by the first drive chain, the second drive chain and the cradle;

Fig.5b: detail of figure 5;

Fig.6: sequence of the upper arms extension, in the telescopic case;

Fig.7: positions of the telescopic upper arms;

Fig.8: rest positions of the attached upper arms, in the modular case;

Fig.9: apparatus in final position for different rig floor heights, for both telescopic and modular upper arms;

Fig.10a: sequence of three different positions of the claw mechanism, in the case where the legs are not telescopic;

Fig.10b: detail of figure 10a. Fig.11 : sequence of three different positions of the claw mechanism, in the case where the legs are telescopic;

Fig.12: partial view of the apparatus according to the invention together with the transfer arm and the cylindrical parts rack.

As shown in figure 1a, 1b, 2a, 2b, 3a, 3b, the apparatus for moving cylindrical parts T according to the invention comprises a support body S, two or three pairs of legs L connected at the upper part thereof to the support body S, the legs L of each pair being situated symmetrically and on opposite sides in respect to the support body S, each leg L being provided with a movable claw mechanism M for transporting along the leg L a cylindrical part T from a region situated at the lower part of the leg L, up to the upper part of the leg L or vice versa. The apparatus further comprises a lower arm LA connected at one of its ends to an extremity of a first actuator A1 that can be a telescopic cylinder (as in figures 1a, 2a, 3a, 4, 9) or a scissor-cylinder system (as in figures 1 b, 2b, 3b, 6). The other extremity of the first actuator A1 is fixed to the support body S. Upon the action of the first actuator A1, the lower arm LA can pivot about a joint J in respect to the support body S. The apparatus further comprises a cradle CR situated above the lower arm LA, said cradle CR being provided with a shoe SH that serves as an abutment for the cylindrical part. The shoe SH may be releasably fixed in several positions along the upper surface of the cradle CR, depending on the length of the cylindrical part T.

The cylindrical part T and the shoe SH are not shown in all the figures, in order to simplify the drawings. For the same reason, the driving means of all the actuators are not shown in the figures. Said driving means may be any suitable known means such as a hydraulic pump.

In figures 1a, 2a, 3a, 4, 9 the apparatus is provided with three pair of legs L, but this example is not limitative because in practice it may be provided with at least two pairs of legs L, as shown in figures 1 b, 2b, 3b, 6.

Moreover, in case the apparatus is provided with two pair of legs L, it may be possible to have an embodiment in which one of said pair of legs L are mounted movable along the support body S, on a horizontal rail HR (as shown in figure 1b, 2b, 3b, 6), such that the distance between the pair of legs is adjustable depending of the cylindrical part length. Moreover, it may be possible to have an embodiment in which the legs L are articulated to the support body S such that each leg L is capable to adopt a position in which the length of said leg L is arranged approximately along the length of the support body S. The advantage in this case is that, when the legs L are arranged along the support body S, the apparatus occupies a smaller volume, thus it can be easily accommodated inside a truck.

As seen in figures 1a, 1b and in more detail in figures 4, 5a, 5b, the lower arm LA is provided with a first drive chain CH1 arranged in an elongated loop extending along the entire length of the lower arm LA. The first drive chain CH1 is driven by a second actuator A2. A second drive chain CH2 is arranged in an elongated loop and mounted in a frame between the lower arm LA and the cradle CR. The second drive chain CH2 has a first chain link fixed to the lower arm LA by means of a first connection element C1. The frame is connected to the first drive chain CH1 by means of a second connection element C2. The second drive chain CH2 has a second chain link, opposed to the first chain link, fixed to the cradle CR by means of a third connection element C3.

Upon driving the first drive chain CH1 by the second actuator A2, the second drive chain CH2 together with its frame and with the second connection element C2 moves relative to both the first drive chain CH1 and the lower arm LA, between a first extreme position and a second extreme position, while at the same time the cradle CR together with the third connection element C3 is capable to move relative to the first and second drive chains CH1, CH2 and relative to the lower arm LA, between a first cradle extreme position and a second cradle extreme position.

In figure 5a, the view I is when the second drive chain CH2 and the cradle CR are in their respective first extreme position; the view II is when the second drive chain CH2 and the cradle CR are in a respective intermediate position; the view III is when the second drive chain CH2 and the cradle CR are in their respective second extreme position.

The first drive chain CH1 is driven by a second actuator A2 of any suitable means (not shown in detail in the figures, only its position), such as a hydraulic engine.

The frame of the second drive chain CH2 is driven by the first drive chain CH1 through the second connection element C2. Such an arrangement and connections between the lower arm LA, the first and second drive chains CH1, CH2, the second actuator A2 and the cradle CR, ensures that the cradle CR moves with double speed (and implicitly performs a double travel distance) relative to the lower arm LA in comparison to the speed and travel distance of the second chain CH2 relative to said lower arm LA.

As seen in figure 6, the support structure for the cradle CR while moving from the first cradle extreme position to the second cradle extreme position are, successively, the upper arms UA1, UA2, UA3.

The upper arms can be telescopic, extended from the lower arm LA, or modular, attached to the lower arm LA.

In case of telescopic upper arms (figures 6 and 7), the cradle CR is attached to the top of the first upper arm UA1. Under the action of the first actuator A1 , the lower arm LA is pivoting around the support body S about the hinge J, until the desired angle, depending on the working area height, is reached (figures 3a, 3b).

Upon its travel forward, the cradle CR will firstly extend the first upper arm UA1, and then, through a first set of bumpers B, the first upper arm UA1 will extend the second upper arm UA2 and the second upper arm UA2 will extend the third upper arm UA3 through a second set of bumpers B. When the cradle CR travels backward, the first upper arm UA1 will retract first, then the first set of bumpers B will retract the second upper arm UA2 and eventually the second set of bumpers B will retract the third upper arm UA3, all the upper arms inside the lower arm LA as shown in figure 7.

In case of modular upper arms (figure 8), a first upper arm UA1 is hinged to the extremity of the lower arm LA situated close to the first actuator A1 , through a joint H provided on top of said extremity of the lower arm LA, and is suitable for a working area (for example a rig floor) height up to 7m. For working area heights between 7m and 10m, the second upper arm UA2 is attached fixed and in extension to the first upper arm UA1. For a working area height between 10m and 15m the third upper arm UA3 is attached fixed and in extension to the second upper arm UA2. Under the action of the first actuator A1, the lower arm LA is pivoting around the support body S about the hinge J, and the first upper arm UA1 is pivoting around the lower arm LA about the hinge H, until it is created the travel line for the cradle CR, as shown in figure 9, and under the action of the second actuator A2, as described above, the cradle will deliver the cylindrical part T to the working area (rig floor).

Figure 9 shows the final position of the apparatus for different rig floor heights, with the cylindrical part T delivered in optimal position.

The legs L may be either telescopic, as in figures 1a, 2a, 3a, 4, 9 and 11 or made of one piece, as in figure 1b, 2b, 3b, 6, 10a, 10b and 12.

Figure 10a shows in detail the claw mechanism M corresponding to the embodiment in which each leg L is made of one piece.

In this case, the claw mechanism M comprises:

- a claw CW for grabbing a cylindrical part T thereon,

- a first pair of bearings B1 fixed to the claw CW and capable to roll along a pair of straight paths P1 provided along the length of the leg L,

- an individual bearing B2 or second pair of bearings B2 fixed to the claw CW and capable to roll along a different, individual inclined path P2 provided along the length of the leg L,

- a third actuator A3 capable to move, by means of a lifting element LE, the claw CW from the lower part of the leg L up to the upper part of the leg L or vice versa. The third actuator A3 may be any suitable means such as a hydraulic cylinder.

The lifting element LE is fixed at one extremity to the claw CW and at the other extremity to the support body S. The lifting element is connected to the third actuator A3. The lifting element LE may be any suitable means such as a chain or a cable.

The claw CW, all the bearings B1, B2 and all the paths P1, P2 are located in respect to each other such that, when the claw CW is situated at the upper part of the leg L, it is in a position rotated approximately 60° in respect to the plane of the individual path P2 in comparison to the position of the claw CW when situated at the lower part of the leg L.

Figure 10b shows in detail the position of the bearings B1, B2 and the paths P1, P2. Figure 11 shows in detail the embodiment when each leg L is telescopic.

In this case, each leg L comprises a fixed upper leg member Lf and a mobile lower leg member Lm, the fixed upper leg member Lf being connected to the support body S. A third actuator A3 can move, by means of a first lifting element LE1, the mobile leg member Lm from a protracted position in which the mobile lower leg member Lm is in extension of the fixed upper leg member Lf and almost completely outside the fixed upper leg member Lf, to a retracted position in which the mobile lower leg member Lm is almost completely accommodated within the fixed upper leg member Lf, and vice versa. The first lifting element LE1 is fixed at one extremity to the mobile lower leg member Lm, and at the other extremity to the third actuator A3.

In the case of telescopic legs, the claw mechanism M comprises:

- a claw CW for grabbing a cylindrical part T,

- a first pair of bearings B1 fixed to the claw CW and capable to roll along a pair of straight paths P1 provided along the length of the mobile lower leg member Lm,

- an individual bearing B2 or a second pair of bearings B2 fixed to the claw CW and capable to roll along a different individual inclined path P2 provided along the length of the mobile lower leg member Lm surface,

- a second lifting element LE2 fixed at one extremity to the claw CW and fixed at its other extremity to the lower part of the fixed upper leg member Lf.

Upon activating the third actuator A3, the mobile lower leg member Lm moves relative to the fixed upper leg member Lf, while at the same time the claw CW moves between the lower part of the mobile lower leg member Lm to the upper part of the lower leg member Lm.

The claw CW, all the bearings B1, B2 and all the paths P1, P2 are located in respect to each other such that, when the claw CW is situated at the upper part of the lower leg member Lm and at the same time the lower leg member Lm is in the retracted position, said claw CW is in a position rotated approximately 60° in respect to the plane of the individual path P2 in comparison to the position of the claw CW when situated at the lower part of the lower leg member Lm while the lower leg member Lm is in the protracted position. The third actuator A3 may be any suitable means such as a hydraulic cylinder and the lifting elements LE1 and LE2 may be any suitable means such as a chain or a cable.

Figure 12 shows the way of loading the cylindrical parts T arranged in several rows on a rack PR. A transfer arm TA is inserted, with an end region thereof, under the highest row of cylindrical parts. The extremity of the transfer arm TA that is opposed to said end region is fixed to the leg L in a mariner to create a rolling path of small slope (i.e. an angle of between about 2 to 3 degrees) for the cylindrical part T.

To each leg L situated on the same side of the support body S corresponds an associated transfer arm TA.

Each cylindrical part T will roll from the rack PR on the rolling paths defined by at least two transfer arms TA. Said cylindrical part T will roll until it contacts the leg L. From there, the claw CW grabs the cylindrical part T and lifts it until the upper part of the leg L in a position to roll over the cradle CR.

The apparatus according to the invention functions as follows: first, the apparatus is in the position shown in figure 1a, in which the lower arm LA, and the cradle CR are in a horizontal position and the claw mechanisms M are situated at the lower part of the legs L.

Then, the claw mechanisms M from at least two legs L pick up a cylindrical part T from the rack. The cylindrical part may be situated in the rack at a height within the range 0.2 m - 3 m as shown in figure 12. The cylindrical part may have an outer diameter of up to 30 inch, a length up to 15 m and a weight up to 6 tons. When the length of the cylindrical part T is between 12 m and 15 m, a back extension element E is extended along the lower arm LA, as shown in figure 3b, 6 and 7, in order for the apparatus to be able to accommodate the whole length of the cylindrical part T. The back extension element E is situated opposed in respect to the at least one upper arm UA1 , figure 6. After the cylindrical part T was picked up by the claw mechanisms M, the cylindrical part T initially rests on the claws CW. Under the action of the third actuator A3 the cylindrical part T is lifted/moved from the lower part of the legs L up to the upper part of the legs L. The above mentioned movement sequence is shown in figures 10 and 11. The movement of the claw CW is accomplished by the rolling of the bearings B1 , B2 along their corresponding paths P1 and P2, figure 10b. The pair of straight paths P1 are parallel to the longitudinal axis of the leg L. The individual straight path P2 is inclined in respect to the longitudinal axis of the leg L and implicitly in respect to the paths P1. Due to this arrangement, when the claw CW is situated at the upper part of the leg L, it is in a position rotated approximately 60° in respect to the plane of the individual path P2 in comparison to the position of the claw CW when situated at the lower part of the leg L. The consequence of this 60° claws rotation is that the cylindrical part T, under the effect of its own weight, rolls from the claws CW down in the cradle CR.

In order to ensure that the cylindrical part T does not remain stuck somewhere between the upper part of the legs L and the cradle CR, the apparatus may further comprise cams CAM, as shown in figure 10a. A respective cam CAM is hinged at the upper part of each leg L such that when the claws CW are at the upper part of the legs L, a part of the claw mechanisms M (for example the frontal part of the claw CW) pushes the respective cam CAM and tilts it about the hinge, such that a surface of the respective cam CAM and a surface of the claw CW together define a continuous inclined rolling surface for the cylindrical part T, said continuous inclined rolling surface being capable to guide the cylindrical part T directly in the cradle CR.

Although the cam CAM is present only in figure 10a (i.e. in the embodiment where each leg L is made from one piece), the embodiment of figure 11 (where teach leg L is telescopic) may equally be provided with a cam CAM.

After the cylindrical part T is positioned in the cradle CR, the first actuator A1 is extended, as shown in figures 2a, 2b, 3a, 3b, such that the lower arm LA (and implicitly the cradle CR and if the case at least one upper arm UA1) pivots around the joint J, as seen in figures 6 and 9. The pivoting angle depends on the working situation and may be within the range between 0° and 32°.

After the desired pivoting angle has been reached, if the case, at least one upper arm UA1 is extended along the lower arm LA, and upon the action of the second actuator A2, the cradle CR will reach the desired extended position. Figures 5a and 7 show the sequence of the cradle CR (for simplicity, the cylindrical part is not shown) movement between its extreme positions: (I) the second drive chain CH2 and the cradle CR are in their respective first extreme positions, (II) the second drive chain CH2 and the cradle CR are respectively in intermediate positions, (III) the second drive chain CH2 and the cradle CR are in their respective second extreme positions, where, for 10 m to 15 m rig floor heights, the cradle CR is completely outside of the lower arm LA, the top of the cradle CR reaches the top of the third upper arm UA3 in case of modular upper arms, or is connected to the top of the first upper arm UA1 in case of telescopic upper arms.

Both respective extreme positions of the second drive chain CH2 and of the cradle CR are defined by corresponding stopping members (not shown in figures for simplicity reason) for the respective connection elements C2 and C3, or depending on the working area height.

In other words, the apparatus works in the following way:

- initially, the second drive chain CH2 and the cradle CR are in their respective first extreme positions;

- the second actuator A2 is activated, driving the first driving chain CH1 in a first direction;

- the driving of the first drive chain CH1 automatically determines the displacement of the second drive chain CH2 and of the cradle CR, due to the fact that the frame of the second drive chain CH2 is connected to the first drive chain CH1 by means of the second connection element C2 and the cradle CR is connected to the second drive chain CH2 by means of the third connection element C3;

- due to the fact that the second drive chain CH2 has a first chain link fixed to the lower arm LA by means of the first connection C1 , and has a second chain link, opposed to said first chain link, fixed to the cradle CR by means of the third connection element C3, the cradle CR automatically moves along the second drive chain CH2 (while at the same time both the second drive chain CH2 together with the cradle CR move along the first drive chain CH1);

- the first drive chain CH1 is driven until the second drive chain CH2 and the cradle CR reach their respective second extreme positions; - in order to restore the second drive chain CH2 and the cradle CR to their respective first extreme positions, the second actuator A2 is activated such that the first drive chain CH1 is driven in a direction opposed to the first direction.

A clearer view of the connection elements C1, C2, C3 of the driving chains CH1, CH2 and of the cradle CR is shown in the details of figure 4.

Due to the simultaneous action of the driving chains CH1, CH2, the time needed for the cradle CR to move between its two extreme positions is 50% shorter than the time needed in the case of the apparatus disclosed in prior art document WO201 3/06933A1.

Also of great importance is the fact that the cradle CR of the apparatus according to the invention can travel outside of the lower arm LA, being able to reach much higher working areas.