IT201900000831A1 - Wire cutting unit and cutting machine that implements said wire cutting unit - Google Patents

Description

Description of the patent for industrial invention entitled: "WIRE CUTTING GROUP AND CUTTING MACHINE THAT IMPLEMENTS SAID WIRE CUTTING GROUP"

DESCRIPTION

Scope of the invention

The present invention is placed in the field of cutting machines using a cutting wire and, in particular, it refers to a cutting unit that can be implemented in said cutting machines.

Furthermore, the present invention relates to a cutting machine which comprises said cutting unit.

State of the art

Cutting machines are known which use a cutting wire to cut a piece or a block - generally large - into several portions. The cutting wire, for example a diamond wire, is shaped like a closed ring and suitably guided and operated produces a cutting movement. These cutting machines, ordinarily used in the processing of stone materials, include a portal structure that defines a gap in which the piece to be cut is placed. A respective cutting head or group is arranged in a sliding manner on the uprights of the portal structure. Each cutting head is movable along its respective upright and comprises a series of pulleys which guide the cutting wire. A motor unit, also formed by a series of pulleys, provides the motion to the cutting wire, which runs guided by the cutting heads in order to define a plane and a cutting path. The cutting machine also comprises a tensioning unit adapted to keep the cutting wire under tension, compensating for the variation in length when the planes of the cutting trajectory change. In addition to the aforementioned application, the use of cutting machines with cutting wire to dissect parts or components of nuclear plants is also known. The purpose is to divide these components into several parts in order to be able to transport and dispose of them in an easy and safe way. We speak, for example, of the metal structure of a nuclear reactor with a linear length of several meters which can have a wall thickness in the order of tens of centimeters. An important aspect of the cutting phases in this area is to ensure appropriate shielding of the piece and the machine during the cutting phase, so that the operator who controls and manages the cutting phases is not subject to component radiation.

Therefore, unlike what happens in a non-radioactive material cutting operating cycle, the operator cannot act directly on the machine in order to change the cutting settings.

In fact, in the current technique, the sequence of the cutting phases takes place by means of an operator who from time to time changes the cutting settings, in particular the trajectory of the cutting wire in order to modify the cutting plane by acting directly on the pulleys or pulleys that guide the cutting line. In this way, it is possible to split using a combination of different cutting planes, for example a double longitudinal cut and a single transverse cut. In the application of cutting radioactive components, these settings cannot occur directly and therefore the need is felt to prepare a cutting machine capable of solving this problem.

Summary of the invention

It is therefore an object of the present invention to provide a cutting unit which allows to selectively vary the cutting plane in order to be able to divide and break the piece to be cut into several portions with transverse and / or longitudinal cuts. Another purpose of the present invention is to provide a cutting unit that allows you to vary the cutting plane remotely without the aid of an operator who operates directly on the cutting unit.

It is also an object of the present invention to provide a cutting unit which allows performing a combination of transverse and longitudinal cuts on the same piece with high precision.

These for other purposes are achieved by a wire cutting unit comprising:

a support frame;

at least a first pulley mounted on said support frame, a cutting wire mounted on said first pulley, wherein said first pulley defines a first cutting plane for said cutting wire,

a support arm which comprises at least a second pulley, in which said support arm is rotatably connected to said support frame and selectively movable between:

a first configuration in which said support arm is moved towards said cutting wire to bring said second pulley into contact with said cutting wire, so that said second pulley is active in guiding said cutting wire in combination with said first pulley, so as to define a second cutting plane for said cutting wire which intersects said first cutting plane,

a second configuration in which said support arm is spaced apart from said cutting wire keeping said second pulley inactive and said first cutting plane unchanged.

In this way, the cutting unit according to the present invention makes it possible to vary the cutting plane according to two intersecting planes, for example a longitudinal plane and a transversal plane, by means of the interposition of a second pulley, mounted movably on board of the main support frame. The second pulley comes into play when it is necessary to vary the first cutting plane.

In particular, the cutting wire is mounted on the first pulley on which it partially winds to be guided slidingly according to a determined cutting trajectory. The trajectory of the cutting line defines the cutting plane which corresponds to the plane on which the cutting line lies.

The cutting line proceeds along the cutting plane during the cutting progress, for example a cross cut in a direction from top to bottom, or a longitudinal cut - when the second pulley is active - from a front position to a rear position.

In order to vary the cutting plane, the support arm is activated which comprises the second pulley mounted idle around its own axis. The support arm rotates around a second axis of rotation. The second axis of rotation is substantially parallel to the axis of rotation of the first pulley.

The second pulley - when in the first configuration - lies on a plane intersecting the first cutting plane, in particular a plane orthogonal to the first cutting plane.

The interposition of the second pulley allows the cutting wire to move along said second cutting plane.

In other words, the second pulley creates a contrast for the cutting wire so that it maintains its position within the guide groove of the pulleys in the phase of contact with the piece to be cut. In fact, the contact of the cutting wire with the piece gives rise to a reaction force that would tend to derail the cutting wire from the first pulley, when making cuts with the second cutting plane.

Advantageously, actuation means are provided which allow to move said support arm between said first and second configuration. In this way, the actuation means mounted on board the cutting unit allow the movement of the support arm from a remote position and without the aid of a direct operator.

Advantageously, said actuation means comprise a first actuator, in particular a rotary actuator, adapted to move said support arm around a first axis of rotation.

Preferably, said second cutting plane orthogonally intersects said first cutting plane.

In particular, said first pulley is mounted on a crank rotatably connected to said support frame having a first axis of rotation.

Advantageously, said crank is actuated by means of a second rotary actuator adapted to vary the angular position of the same and therefore of the first pulley. In this way, the first pulley is mounted eccentric on the support frame with respect to the first axis of rotation, and is movable in order to assume distinct angular positions. In this embodiment, the movement of the crank allows you to vary the position of the first pulley and therefore its alignment with the cutting wire when the second pulley comes into play. In particular, the displacement of the first pulley allows the cutting edge to be aligned at the height of the second pulley when the latter is placed in the first configuration. In addition, in other cutting configurations the movement of the first pulley by means of the crank allows to optimize the guiding of the cutting wire, maximizing the angular support portion that the cutting wire has with the pulley or pulleys.

This position variation takes place by means of the second actuator, which is part of said actuation means, which activates the crank rotatably. This adjustment is mainly necessary so that there is no derailment of the cutting edge from the first and second pulley.

In detail, the crank defines an arm with respect to the first axis of rotation. The crank is rotatably connected to the first axis of rotation at a first end thereof, while the first pulley is rotatably connected to a second end of the crank, opposite the first end.

The first pulley is mounted idle on the crank around its own axis of rotation, while the crank is activated by the second actuator, in particular a rotary actuator, which allows it to rotate around the first axis of rotation and therefore with respect to the support frame.

Advantageously, a support plate is provided rotatably mounted on said support arm around a third axis of rotation. The third axis of rotation is substantially orthogonal to the second axis of rotation of the support arm.

Said second pulley is rotatably mounted on said support plate. Preferably, said support plate is connected to a third actuator, forming part of said actuation means, able to move said support plate around said third axis of rotation. The support plate operated by means of said third actuator, in particular a linear actuator, allows the approach of the second pulley to the cutting wire. In particular, when the support arm moves into the first configuration, the second pulley is in line with the cutting wire but not yet in contact. Contact occurs by rotating the support plate until the cutting wire enters the guide of the second pulley so as to be tangent to it. The passage in the first configuration therefore takes place in two distinct movements: a first rotation of the support arm which brings the second pulley in line with the cutting wire, and a second rotation of the support plate which determines the tangent contact of the cutting wire with the second pulley.

In other words, the second pulley is first placed in proximity to the cutting edge and then brought close to it in a substantially tangent position to the cutting edge, so that the cutting edge also comes into contact with the second pulley and is slidingly guided by the cutting edge. combination of the first and second pulley.

Advantageously, said third actuator extends between a first connection portion formed on said support arm and a second connection portion formed on said support plate.

In particular, proximity sensors are provided in correspondence with:

of said support arm,

of said first pulley,

of said second pulley, or a combination thereof.

Preferably said proximity sensors are arranged on board of said cutting unit. In particular, said sensors functionally associated with said actuation means and / or said pulleys and / or said support arm, and / or said support plate. In this way, the proximity sensors detect the correct movement of the second pulley in the first configuration, avoiding that there are preliminary contacts of the same with the cutting wire.

This aspect is important to monitor the correct positioning of the cutting wire during the cutting phase itself. In addition, it allows the cutting plane to be varied, passing between a transverse plane and a longitudinal plane, without interrupting the motion of the cutting wire. The sensors therefore ensure that in passing from one cutting plane to another, the support arm rotates completely, aligning itself with the cutting wire.

In a preferred embodiment, a first group of pulleys is provided mounted on said support frame,

the cutting wire being arranged on said first group of pulleys to define the first cutting plane.

Preferably the support arm comprises a second group of pulleys to define said second cutting plane. When the second group of pulleys is in the second configuration, the cutting wire is enclosed on opposite sides by the pulleys of the second group, substantially tangent to said pulleys.

In this way, the provision of a first and a second group of pulleys allows to carry out multidirectional cuts, i.e. cuts with a cutting direction that goes from top to bottom and vice versa, or cuts with a cutting direction directed from one side. front of the piece towards a rear part or vice versa.

In particular, a control unit is provided which is adapted to control said actuation means, in particular said first actuator, said second actuator and said third actuator, or a combination thereof. Said control unit includes a remote interface for an operator through which the operator acts to vary and adjust the cutting configuration for each cutting group. The control unit is also functionally connected to the proximity sensors that can be viewed on the interface. The interface preparation allows the operator to operate on the cutting parameters from a remote location. Therefore, to dissect radioactive components, the operator is well shielded and protected as he is at a safe distance. Advantageously, said first group of pulleys comprises said first pulley and a first complementary pulley, and said second group of pulleys comprises said second pulley and a second complementary pulley.

Preferably, said first complementary pulley is rotatably mounted idle on said support frame in a fixed position about its own axis of rotation and spaced with respect to said first pulley. That is, the axis of rotation of the first complementary pulley is spaced from the first axis of rotation of the crank.

Advantageously, said first pulley and said first complementary pulley lie on the same plane.

In particular, the first complementary pulley is mounted coaxially to said first axis of rotation on the opposite side with respect to said support arm.

In particular, said second pulley and said second complementary pulley are rotatably mounted on said support plate, spaced apart from each other.

Advantageously, said second pulley and said second complementary pulley lie on the same plane.

In particular, the crank on which the first pulley is arranged has a length such that the first pulley in rotation around the first axis of rotation interferes with the first complementary pulley. In other words, the rotation of the first pulley by means of the crank is limited around a circular sector ranging from -20 ° to about 210 ° clockwise. Beyond these angular limits, the first pulley interferes with the first complementary pulley, that is, it comes into contact with it. Since the rotation beyond the aforesaid limits is not functional, the mutual distance between the first pulleys has been reduced, thus allowing to reduce the overall dimensions.

The first crank therefore moves in an angular range of about 230 ° in particular in a circular sector on the opposite side with respect to the first complementary pulley.

The predisposition of the first complementary pulley in combination with the first pulley allows to make transversal or vertical cuts, in other words according to the first cutting plane, in both directions with movement of the cutting wire directed from top to bottom and from below upward.

This type of transversal cut provides that there are two cutting units mounted specularly and on opposite sides on a support portal of a cutting machine which uses a cutting unit according to the present invention. For the transverse cut, the support arm and the respective pulleys of the second group of pulleys do not come into play and therefore are in the second configuration. For each cutting group, the transverse cut from top to bottom is obtained by rotating the first pulley upwards with a substantially vertical position of the crank - in a front view. Thus, the first pulley is higher - seen in a frontal plane - than the first complementary pulley. This configuration determines a path of the cutting wire which, starting from the top, wraps itself partially on the first pulley and is guided tangentially in the lower part of the same towards the first complementary pulley which - in turn - guides the cutting wire tangentially in the upper portion. In other words, the cutting wire is enclosed on opposite sides by the first pulley and by the first complementary pulley.

In summary, for the transverse cut from top to bottom the second group of pulleys on the support arm are not useful and therefore must be placed away from the trajectory of the diamond wire, or in the second configuration. The first pulley of the first group of pulleys, on the other hand, has the task of dragging the wire against the part to be cut and therefore is rotated until it reaches tangency with the first complementary pulley. The latter for this type of cut does not perform a specific task, other than a guide.

On the other hand, in a cut from the bottom up, the first pulley is rotated downwards, always with a downward orientation of the crank.

In this case, the first complementary pulley has the task of dragging the wire against the part to be cut, while the first pulley must guarantee the cutting wire a correct covering on the first complementary pulley and therefore the first pulley must be rotated until the as much coverage as possible of the wire on the first complementary pulley.

In order to make a longitudinal cut, on the other hand, the second group of pulleys comes into play, which are rotated in order to assume the first configuration. In this case, in fact, the pulleys which have the task of dragging the wire against the part to be cut are said second pulley and said second complementary pulley according to the direction of motion. In this context, the two pulleys are forced to approach the cutting edge and to arrange themselves in a configuration tangent to both by means of the rotation of the support plate. The latter is moved by means of the linear actuator in which it extends a certain stroke which determines the rotation of the support plate around the third axis of rotation, and therefore determines the alignment of the second pulleys with the cutting wire.

The first pulley and the first complementary pulley, on the other hand, must favor the circulation of the cutting wire, guaranteeing a precise entry of the same towards the pulleys of the second group.

Finally, the cutting unit allows to perform longitudinal cuts in which, with respect to the horizontal and longitudinal cut in both directions of motion, the cutting edge is inclined at a desired angle. The angle is given by the reciprocal position of the cutting groups which will take on different levels along the respective uprights.

In this case, the second pulley and the second complementary pulley will assume an inclined position, which will correspond to a precise rotation of the support arm, which will be identical to the angle defined by the cutting wire.

In this case, it is necessary to specify that the two cutting groups with reference to the first group of pulleys will assume an opposite configuration. In fact, the first pulley of the cutting unit with a lower position on the respective upright assumes a position with the crank facing downwards. On the opposite side, however, in the cutting unit with a higher position on the respective upright, the first pulley assumes a configuration facing upwards. The opposite orientation of the first pulleys in the two cutting groups is simply due to the correct winding of the cutting wire on the pulleys in order to optimize its stability and guidance.

Preferably, said support frame is shaped to be mounted on a bearing element adapted to move said cutting unit.

Advantageously, said bearing element being selected from: a handling arm,

an upright of a support portal,

a combination of them.

According to another aspect of the invention, a cutting machine is described comprising a portal having a first and a second upright and a crossbar connected between said first and second upright, in which said portal defines a housing opening in which a piece to be cutting, in which said cutting unit is arranged respectively on said first and second upright.

Advantageously, each cutting unit is mounted sliding along the respective upright in a direction from top to bottom and vice versa.

Preferably, a movement arm is provided which is slidably mounted on a respective upright, said cutting unit being provided on said movement arm. In this way, the handling arm is arranged cantilevered with respect to the upright of the cutting machine. The handling arm can advantageously be fixed. Alternatively, the movement arm is rotatably connected to the upright and actuated by means of a fourth actuator, for example a hydraulic cylinder, which allows the variation of its angular position with respect to the upright. In particular, the handling arm has a telescopic structure which also allows its own linear extension. The movement between a retracted configuration and an extended configuration is always carried out by means of the fourth actuator. In this way, the handling arm and therefore the cutting unit can be positioned in spaced positions with respect to the relative upright, up to, for example, a central position in a low or high end of the portal opening is reached. In this configuration it is possible to make a vertical cut with the longitudinal direction of the piece.

Description of the figures of the invention

Further characteristics and advantages of the invention will be better highlighted by examining the following detailed description of several preferred, but not exclusive, embodiments, illustrated by way of non-limiting example, with the support of the attached drawings, in which: - Figure 1 shows a perspective view of a cutting unit in a simplified embodiment according to the present invention, Figure 1 shows the simplified cutting unit in a second configuration to perform a transverse cut;

figure 2 shows a perspective view of the simplified cutting unit of figure 1 according to the present invention, during a transversal cutting step in the second configuration;

Figure 3 shows a perspective view of the simplified cutting unit of Figure 1 in a first configuration for performing a longitudinal cut;

Figure 4 shows a perspective view of the simplified cutting unit of Figure 3 according to the present invention, during a longitudinal cutting step in the first configuration;

figure 5 shows a perspective view of the simplified cutting unit of figure 3 during an inclined longitudinal cutting step;

- Figure 6 shows a perspective view of a cutting unit according to a preferred embodiment in a second configuration to make a transverse cut from top to bottom;

- figure 6A shows a perspective view of the cutting unit of figure 6 during a transversal cutting step from top to bottom performed in the second configuration;

- Figure 6B shows in a front perspective view the cutting units mounted specular on a support portal of a cutting machine during the transversal cutting phase from top to bottom;

- Figure 7 shows a perspective view of the cutting unit according to a preferred embodiment in the second configuration to make a transverse cut from bottom to top;

- figure 7A shows in a perspective view the cutting unit of figure 7 during the transversal cutting step from bottom to top performed in the second configuration;

- Figure 7B shows in a perspective view the cutting units mounted specular on a support portal of a cutting machine during the transversal cutting phase from bottom to top;

figure 8 shows a front view of the first group of pulleys in which the first pulley with crank is in a first angular position;

figure 8A shows a front view of the first group of pulleys of figure 8 in which the first pulley with crank is in a second angular position;

figure 9 shows a perspective view of the cutting unit of figure 6 in a first configuration for making a longitudinal cut;

Figure 10 shows a perspective view from below of the cutting unit of Figure 9 in a first configuration for making a longitudinal cut;

- Figures 11 and 12 show a top view of the actuation phase of the support plate which determines the engagement of the second group of pulleys to make the longitudinal cut;

Figure 13 shows a perspective view of the cutting unit of Figure 6 in the first configuration for making a longitudinal cut;

Figure 13A shows a perspective view of the cutting unit of Figure 13 during the longitudinal cutting step; Figure 13B shows a perspective view of the cutting units mounted specularly on a support portal of a cutting machine during the longitudinal cutting step; Figure 14 shows a perspective view of the cutting units mounted staggered on a support portal of a cutting machine during the longitudinal cutting phase with an inclined cutting wire;

Figure 14A shows a particular perspective view of the cutting unit mounted on the upright of the portal which is in the elevated position with respect to the cutting unit of the opposite upright;

Figure 14B shows a particular perspective view of the cutting unit mounted on the upright of the portal which is in the low position with respect to the cutting unit of the opposite upright;

Figure 15 shows a perspective view of the cutting units mounted opposite each other and for carrying out a vertical longitudinal cut;

Figure 15A shows a particular perspective view of the cutting unit mounted on the upright of the portal which is in the elevated position with respect to the cutting unit of the opposite upright;

Figure 15B shows a particular perspective view of the cutting unit mounted on the upright of the portal which is in the low position with respect to the cutting unit of the opposite upright;

- figures 16, 17 and 18 show in perspective views a cutting machine which implements the cutting units of figures 6 to 15B and other devices for tensioning the thread to actuation devices.

Detailed description of the invention

With reference to Figure 1, a cutting unit 10 is shown which comprises a support frame 1, at least a first pulley 2 mounted on the support frame 1 and a cutting wire 20 mounted on the first pulley 2. The first pulley 2 defines a close-up cutting plane P1 (Fig. 2) for cutting wire 20.

A support arm 3 is also provided which comprises at least a second pulley 4. The support arm 3 is rotatably connected to the support frame 1 and is selectively movable between:

a first configuration B in which the support arm 3 is moved towards the cutting wire 20 to bring the second pulley 4 into contact with the cutting wire 20 (Fig. 3), so that the second pulley 4 is active in the guide of the cutting wire 20 in combination with the first pulley 2. The positioning of the second pulley 4 in the first configuration B allows to define a second cutting plane P2 for the cutting wire 20 which intersects the first cutting plane P1.

In a second configuration A (Fig. 1 and 2), on the other hand, the support arm 3 is spaced from the cutting wire 20 keeping the second pulley 4 inactive and the first cutting plane P1 unchanged.

The movement of the second pulley 4 and the contact of the latter with the cutting edge, allows you to vary the cutting plane by passing from a transverse plane P1 to a longitudinal plane P2. The variation of the cutting plane is possible since the second pulley 4 defines an additional guide for the cutting wire 20 which is arranged on a cutting plane which coincides with the second cutting plane P2. Therefore, the second pulley 4 creates a support for the cutting wire 20 so that it can follow a cutting direction along the second cutting plane P2, as described in detail below.

The first plane P1 and the second plane P2 are identified below as the transverse plane and the longitudinal plane with respect to a piece 100 to be sectioned.

The cutting unit 10 according to the present invention makes it possible to vary the cutting plane according to two intersecting planes, namely the plane P1 and the plane P2. This occurs through the interposition of the second pulley 4 mounted on the support arm 3 which is in turn mobile mounted on the main support frame 1.

In particular, the cutting wire 20 is mounted on the first pulley 2 on which it partially winds to be guided slidingly according to a determined cutting trajectory. The trajectory of the cutting wire 20 defines the cutting plane P1 which corresponds to the plane on which the first pulley 2 lies (Fig.2).

The cutting wire 20 proceeds along the cutting plane during the cutting progress, for example a transverse cut according to a DTL direction from top to bottom (Fig. 2), or a longitudinal cut according to a DFR direction from a position front towards a rear position (Fig. 4).

In order to vary the cutting plane, the support arm 3 is activated which comprises the second pulley 4 mounted idle around its own axis. The support arm 3 instead rotates around a second rotation axis 7 '(Fig. 1 and 2). The second axis of rotation 7 'is substantially parallel to the axis of rotation of the first pulley 2.

The second pulley 4 when moved in the first configuration B (Fig. 3) lies on a plane intersecting the first cutting plane P1, or the second cutting plane P2 which is orthogonal to the first cutting plane P1. The interposition of the second pulley 4 allows the cutting wire 20 to be able to move along the second cutting plane P2 (Fig.4). In other words, the second pulley 4 creates a contrast for the cutting wire 20 so that it maintains its position within the guide of the pulleys 2 and 4 when it comes into contact with the piece 100 to be cut. In fact, the contact of the cutting wire 20 with the piece 100 gives rise to a reaction force which would tend to unseat the cutting wire 20 from the first pulley 2, since the longitudinal cutting direction is perpendicular to the plane of the first pulley 2 .

The movement of the support arm 3 takes place by means of dedicated actuation means which allow the latter to be moved selectively between the first B and the second configuration A. In detail, the actuation means comprise a first actuator 7, in particular an actuator rotary, adapted to move the support arm 3 around a first axis of rotation 7 '. By selectively it is meant that the two configurations A and B can be varied with respect to each other according to the type of cut to be made on the piece 100. In fact, through a combination of transverse and longitudinal cuts, the cutting unit 10 according to the present invention allows the sectioning piece 100 to be divided as desired without the direct aid of an operator who from time to time has to vary the position of the pulleys and of the cutting wire to vary the cutting plane.

In this way, the actuation means mounted on board the cutting unit 10 allow the movement of the support arm 3 from a remote position and without the aid of a direct operator. The combination and variation of the cutting planes can be controlled according to a specific mapping which automatically guides the actuation means and the cutting unit in order to obtain a cut according to a specific specification. This cut can have, for example, a linear or curved trajectory.

In particular, the second cutting plane P2 orthogonally intersects the first cutting plane P1.

According to constructive aspects, the first pulley 2 is mounted on a crank 5 rotatably connected to the support frame 1 having a first axis of rotation 6 '.

The crank 5 is actuated by means of a second rotary actuator 6 adapted to vary the angular position of the crank and therefore of the first pulley 2. In this way, the first pulley 2 is mounted eccentric on the support frame 1 with respect to the first axis of rotation 6 ' , and is movable in order to assume distinct angular positions.

The movement of the crank 5 allows, for example, to vary the position of the first pulley 2 and therefore its alignment with the cutting wire 20 when the second pulley 4 comes into play. Or, it allows to optimize the guiding of the wire. cutting by maximizing the angular portion of the wire in contact with the curvature of the pulley.

In the first configuration shown in figure 3, the movement of the crank 5 allows the movement of the first pulley 2 in order to align the cutting wire 20 at the height of the second pulley 4. In other words, it allows to adjust the height of the wire. cut 20 to bring it in line with the second pulley 4 (Fig. 3). This optimizes the guiding of the cutting line and consequently the resulting cutting precision.

The crank 5 defines an arm measured between the first axis of rotation 6 'and the axis of rotation of the first pulley 2. The crank 5 is rotatably connected to the first axis of rotation 6' at a first end thereof while the first pulley 2 is rotatably connected to a second end of the crank 5, opposite the first end.

The first pulley 2 is mounted idle on the crank 5 around its axis of rotation, while the crank 5 is activated by the second actuator 6 which allows it to rotate around the first axis of rotation 6 'and therefore with respect to the support frame 1.

On the support arm 3 there is a support plate 9 rotatably connected to the latter at an opposite end with respect to the end of the rotatable connection with the support frame 1. The support plate 9 is rotatably mounted around a third rotation axis 9 '. The third axis of rotation 9 'is substantially orthogonal to the second axis of rotation 7' of the support arm 3. Constructively, the support arm 1 is an "L" -shaped element in which the two portions 3a and 3b that define the " L ”are orthogonal to each other (Fig.2). In detail, the first portion 3a faces parallel to the surface of the support frame 1, while the second portion 3b is always orthogonal to the surface of the support frame 1.

The support plate 9 is rotatably connected to the second portion 3b of the support arm 3. The second pulley 4 is rotatably mounted on the support plate 9. The support plate 9 is connected to a second actuator 8 adapted to move the support plate 9 around the third axis of rotation 9 '. The support plate 9 operated by means of the actuator 8, in particular a linear actuator, allows the second pulley 4 to be brought closer to the cutting edge 20. In particular, when the support arm 3 moves into the first configuration, the second pulley 4 is in line with the cutting wire 20 but not yet in contact. Contact occurs by rotating the support plate 9 by means of the extension of the actuator 8 which performs a stroke C (Fig.5) until the cutting wire 20 enters the guide of the second pulley 4 so as to be tangent to it. The passage in the first configuration B therefore takes place in two distinct movements: a first rotation of the support arm 3 which brings the second pulley 4 in line or at the height with the cutting edge 20, and a second rotation of the support plate 9 which determines the tangent contact of the cutting wire 20 with the second pulley 4.

In other words, the second pulley 4 is first rotated to align with the cutting wire 20 and then, by means of the extension of the actuator arm 8, brought into sliding and tangent contact with the cutting wire 20 so that it is slidingly guided by the combination of first and second pulley 4.

The third actuator 8 extends between a first connection portion formed on the support arm 3 and a second connection portion formed on the support plate 9.

In order to ensure correct and safe movement of the support arm 3 but also of the support plate 9, as well as of the crank 5, proximity sensors are advantageously provided in correspondence with:

of said support arm 3, of said first pulley 2, of said second pulley 4, or a combination thereof.

Said proximity sensors are functionally associated with said actuation means, i.e. the first rotary actuator 7, the second rotary actuator 6 and the third linear actuator 8. In this way, the proximity sensors detect the correct movement of the second pulley in the first configuration , avoiding that there are preliminary contacts of the same with the cutting wire 20.

This aspect is important for monitoring correct positioning of the cutting wire 20 during the cutting phase itself. In addition, it allows the cutting plane to be varied, passing between a transverse plane and a longitudinal plane, without interrupting the motion of the cutting wire. The sensors therefore ensure that in passing from one cutting plane to another the support arm 3 completes its full rotation, aligning itself with the cutting wire 20.

The interface preparation allows the operator to operate on the cutting parameters from a remote location. Therefore, to dissect radioactive components, the operator is well shielded and protected as he is at a safe distance.

With reference to figures 6 onwards, a preferred embodiment of the cutting unit 10 is shown which provides a first group of pulleys 2, 2 'mounted on the support frame 1 and a second group of pulleys 4, 4' mounted on the support 3.

The first group of pulleys 2, 2 'defines the first cutting plane P1 (Fig.6), while the second group of pulleys 4, 4' defines the second cutting plane P2 (Fig.13A). When the second group of pulleys 4, 4 'is in the first configuration B, the cutting wire 20 is enclosed on opposite sides by the pulleys 4, 4' of the second group, resulting substantially tangent to the pulleys (Fig. 13), as described below in details.

In this way, the provision of a first 2, 2 'and a second group of pulleys 4, 4' allows to perform multi-direction cuts, i.e. transversal cuts with cutting direction DTL going from top to bottom (Fig. 6B) or DLT cutting direction that goes from bottom to top (Fig. 7B), or longitudinal cuts with DFR cutting direction that goes from a front part of the piece 100 towards a rear part or cut along a DRF direction that goes from a rear part of the piece 100 towards a front part (Fig.13B).

In particular, a control unit is provided which is adapted to control the actuation means, in particular the first actuator 7, the second actuator 6 and the third actuator 8, or a combination thereof. The control unit includes a remote interface for an operator through which the operator acts to vary and adjust the cutting configuration for each 10.10 'cutting group. The control unit is also functionally connected to the proximity sensors that can be viewed on the interface. The interface preparation allows the operator to operate on the cutting parameters from a remote location. Therefore, to dissect radioactive components, the operator is well shielded and protected as he is at a safe distance.

In detail, the first group of pulleys 2, 2 'includes the first pulley 2 and a first complementary pulley 2', and the second group of pulleys 4, 4 'includes the second pulley 4 and a second complementary pulley 4'.

The first complementary pulley 2 'is rotatably mounted idle on the support frame 1 in a fixed position around its own axis of rotation and spaced with respect to the first pulley 2. The axis of rotation of the first complementary pulley 2' is spaced from the first axis of rotation rotation 6 'of the crank 5. The first pulley 2 and the first complementary pulley 2' lie on the same plane and rotate about respective rotation axes 14, 14 '. In particular, the first complementary pulley 2 'is mounted coaxially to the second rotation axis 7' on the opposite side with respect to the support arm 3.

In particular, the second pulley 4 and the second complementary pulley 4 'are rotatably mounted on the support plate 9, spaced apart from each other. The second pulley 4 and the second complementary pulley 4 'lie on the same plane.

In particular, the crank 5 on which the first pulley 2 is arranged has a length such that the first pulley 2 in rotation around the first axis of rotation 6 'interferes with the first complementary pulley 2'. In other words, the rotation of the first pulley 2 by means of the crank 5 is limited around a circular sector ranging from -20 ° to about 210 ° clockwise. Beyond these angular limits, the first pulley 2 interferes with the first complementary pulley 2 ', or comes into contact with it. Since the rotation beyond the aforesaid limits is not functional, the mutual distance between the first pulleys has been reduced, thus allowing to reduce the overall dimensions.

The first crank 5 therefore moves in an angular range of about 230 ° in particular in a circular sector on the opposite side with respect to the first complementary pulley 2 '. The arrangement of the first complementary pulley 2 'in combination with the first pulley 2 allows transversal cuts to be made, according to the first cutting plane P1, in both directions with movement of the cutting wire 20 directed from the top downwards DTL and from the bottom to top DLT.

This type of transversal cut requires that there are two cutting units 10, 10 'mounted specularly and on opposite sides on a support portal 400 (Fig.6B) of a cutting machine.

For the transverse cut, the support arm 3 and the respective pulleys 4 and 4 'of the second group of pulleys do not come into play and therefore are in the second configuration A.

For each cutting unit 10 the transverse cut from top to bottom is obtained by rotating the first pulley 2 upwards with a substantially vertical position of the crank 5 - in a front view (Fig.8). In this way, the first pulley 2 is higher - seen in a frontal plane - compared to the first complementary pulley 2 '. This configuration determines a path of the cutting wire 20 which, starting from the top, partially winds on the first pulley 2 and is guided tangentially in its lower part towards the first complementary pulley 2 'which - in turn - guides the cutting wire tangentially. 20 in the upper portion. In other words, the cutting wire 20 is enclosed on opposite sides by the first pulley 2 and by the first complementary pulley 2 '.

In summary, for the transversal cut from top to bottom the second group of pulleys 4, 4 'on the support arm 3 are not useful and therefore must be placed away from the trajectory of the diamond wire, or in the second configuration. The first pulley 2 of the first group of pulleys 2, 2 'has instead the task of dragging the wire against the part to be cut and therefore is rotated until it reaches tangency with the first complementary pulley 2'.

In a cut from the bottom upwards with DLT direction (Fig. 7B), on the other hand, the first pulley 2 is rotated downwards (Fig.7 and 8A) always with a downward orientation of the crank 5. In this case, the first complementary pulley 2 'has the task of dragging the wire against the part to be cut, while the first pulley 2 is oriented to maximize the angular portion of the pulley covered by the cutting wire 20, i.e. in contact with the wire cutting edge 20. Such an arrangement of the first pulley 2 will consequently maximize the angular portion covered by the cutting edge 20 also for the first complementary pulley 2 '. In this way, the guiding stability of the cutting line and therefore the precision of the cut itself is optimized.

To operate a longitudinal cut, the second group of pulleys 4, 4 'comes into play, which are placed in the first configuration B (Fig. 9 and 10).

In this case, in fact, the pulleys that have the task of dragging the wire against the part to be cut are the second pulley 4 and the second complementary pulley 4 'depending on the direction of motion. In this context, the two pulleys are forced to approach the cutting wire 20 and to arrange themselves in a configuration tangent to both. The first pulley 2 and the first complementary pulley 2 ', on the other hand, will have to favor the circulation of the cutting wire 20 ensuring a precise entry of the same towards the pulleys of the second group.

Also in this case the rotation of the support arm 3 and the contact of the second group of pulleys 4, 4 'occurs by means of the rotation of the support plate 9 on which they are mounted. The support plate 9 is operated by the linear actuator 8 between a first retracted configuration of the actuation arm (Fig.11) and an extended configuration of the actuation arm that performs a stroke C (Fig.12). The rotation of the support plate 9 determines the simultaneous contact of the cutting wire 20 with both the second pulleys 4 and 4 '.

In this cutting configuration, the first pulley 2 is in the position of the crank 5 oriented upwards (Fig. 13) in order to align the cutting edge 20 with the pair of pulleys 4 and 4 'of the second group.

Finally, as shown in Figures 14, 14A and 14B, the cutting unit 10 allows to perform longitudinal cuts in which, with respect to the horizontal and longitudinal cut in both directions of motion, the cutting wire 20 is inclined at a desired angle. The angle is given by the mutual position of the cutting units 10 and 10 'which will take on different levels along the respective uprights 40 and 40'.

In this case, the second pulley 4 and the second complementary pulley 4 'will assume an inclined position (Fig. 14 A and 14B), which will correspond to a precise rotation of the support arm 3 and will be identical to the angle defined by the cutting wire 20.

In this case, it is necessary to specify that the two cutting groups 10 and 10 'with reference to the first group of pulleys 2, 2' will assume an opposite configuration. In fact, in the cutting unit 10 'with a higher position, the first pulley 2 assumes a configuration facing upwards (Fig. 14A), while the first pulley 2 of the cutting unit 10 with a lower position on the upright assumes a position with the crank 5 facing downwards (Fig.14B). The opposite orientation of the first pulleys 2 in the two cutting groups 10 and 10 'is due to maintain a correct trajectory of the cutting wire 20.

In a further type of cut, shown in figures 15, 15A and 15B, the cutting units 10 and 10 'are moved in the middle of the support portal 400 in order to make a vertical cut. In this case the support arm 3 and the respective pulleys 4 and 4 'of the second group are oriented at an angle of 90 ° with respect to the support frame 1 to align with the direction of the cutting wire 20. Also in this case, the first pulleys 2 for the respective cutting units 10 and 10 'are oriented staggered with respect to each other.

Preferably, the support frame 1 is shaped to be mounted on a bearing element adapted to move the cutting unit 10.

Advantageously, the bearing element being selected from a handling arm 30 as shown in figure 1 for the first embodiment, or in figure 6 for the second embodiment.

Or the bearing element is given by the combination of the handling arm 30 with the upright 40, 40 'of the support portal 400. Alternatively, the cutting unit 10 can be arranged on a robotic arm or other similar type of support.

Figures 16, 17 and 18 show a cutting machine 200 which implements the cutting units 10, 10 'according to the present invention.

The cutting machine 200 comprises a portal 400 with a first 40 and a second 40 'upright opposite each other, and connected at the top by a crosspiece 45 which extends between the first 40 and second 40' upright. The portal 400 defines a housing opening S in which a piece 100 to be cut is arranged. On the first 40 and second 40 'upright there is a respective cutting unit 10, 10' as described above.

In a preferred embodiment, a movement arm 30 is provided, mounted slidingly on a respective upright 40, 40 '(Fig. 1). A respective cutting unit 10, 10 'is arranged on said movement arm 30.

The handling arm 30 is arranged cantilevered with respect to the upright 40, 40 'of the cutting machine 200. The handling arm 30 can be fixed, for example like that of figure 15. Alternatively, the handling arm 30 is connected to the upright 40, 40 'and actuated by means of a fourth actuator 35 (Fig.7B, 13B), for example a hydraulic cylinder, which allows the variation of its length and / or angular position with respect to the upright 40,40'. In particular, the handling arm 30 has a telescopic structure which also allows its own linear extension. The movement between a retracted configuration and an extended configuration is always carried out by means of the fourth actuator 35. In this way, the handling arm and therefore the cutting unit 10, 10 'can be positioned in spaced positions with respect to the relative upright 40, 40 ', until, for example, a central position is reached in a low or high end of the opening S of the portal 400. In this configuration it is possible to make a vertical cut with a longitudinal direction of the piece.

The cutting machine 200 is also equipped with a tensioning unit 50. The purpose of this unit is to supply the correct tension to the wire at each stage of the process. The right tension also serves to ensure compliance with the required path of the wire in the pulley grooves. This tensioning system is achieved by means of hydraulic devices which impart the correct and constant force to the group of idle pulleys arranged on a suitably guided mobile carriage. The device also constitutes a large yarn store with different purposes; compensate for the variation in length of the wire to allow cuts of pieces with very high sections, allow the use of wire rings with a development that allows the execution of the cut in a single cycle, longer life of the cutting edges and therefore few interruptions. Two “tunnels” crossed longitudinally by the diamond wire are combined with the tensioning unit with the function of cooling it. This cooling is achieved by blowing compressed air through nozzles suitably arranged along the "tunnel".

Furthermore. the cutting machine comprises a motorized head 60. The motorized head is composed of a structure which houses the three pulleys intended to drive the cutting wire 20; the pulleys in turn are mounted on hydraulic motors by means of keyed flanges. The pulleys are equipped with suitable grooves capable of accommodating a replaceable lining as a function of the inevitable wear due to operation. The three hydraulic motors are connected in parallel and are arranged according to the suitable scheme to favor the maximum adherence of the wire. The canopy, which can be easily opened, has the function of protection and shelter, without preventing the quick removal and replacement of the cutting wire 20.

The above description of one or more specific embodiments is able to show the invention from the conceptual point of view so that others, using the known technique, will be able to modify and / or adapt the embodiments in various applications without further research. and without departing from the inventive concept, and, therefore, it is understood that such adaptations and modifications will be considered as equivalent to the specific embodiment. The means and materials for carrying out the various functions described may be of various nature without thereby departing from the scope of the invention. It is understood that the expressions or terminology used have a purely descriptive purpose and are therefore not limiting.

Claims (10)

CLAIMS 1. Wire cutting unit (10) comprising: - a support frame (1); - at least one first pulley (2) mounted on said support frame (1), - a cutting wire (20) mounted on said first pulley (2), in which said first pulley (2) defines a first cutting plane (P1) for said cutting wire (20), - a support arm (3) which comprises at least a second pulley (4), in which said support arm (3) is rotatably connected to said support frame (1) and selectively movable between: a first configuration (B) in which said support arm (3) is moved towards said cutting wire (20) to bring said second pulley (4) into contact with said cutting wire (20), so that said second pulley (4) is active in the guide of said cutting wire (20) in combination with said first pulley (2), so as to define a second cutting plane (P2) for said cutting wire (20) which intersects said cut close-up (P1), a second configuration (A) in which said support arm (3) is spaced from said cutting wire (20) keeping said second pulley (4) inactive and said first cutting plane (P1) unchanged. 2. Cutting unit (10) according to claim 1, in which actuation means (7) are provided which allow to move said support arm (3) between said first configuration (B) and said second configuration (A), preferably said actuation means comprise a first actuator (7), in particular a rotary actuator, adapted to move said support arm (3) around a first axis of rotation (7 '). Cutting unit (10) according to claims 1-2, wherein said second cutting plane (P2) orthogonally intersects said first cutting plane (P1). Cutting unit (10) according to claims 1-3, wherein said first pulley (2) is mounted on a crank (5) rotatably connected to said support frame (1) with respect to a first axis of rotation (6 '), in particular said crank (5) is actuated by means of a second rotary actuator (6) forming part of said actuation means, adapted to vary the angular position of said crank (5) and therefore the position of said first pulley (2 ). 5. Cutting unit (10) according to claims 1-4, in which a support plate (9) is provided rotatably mounted on said support arm (3) around a third axis of rotation (9 '), in particular said second pulley (4) is rotatably mounted on said support plate (9), in particular said support plate (9) is connected to a third actuator (8), which is part of said actuation means, able to move said plate support (9) around said third axis of rotation (9 ') so as to bring the second pulley (4) closer to the cutting wire (20) in said first configuration (B). 6. Cutting unit (10) according to claims 2-5, in which there is provided a control unit able to control said actuation means (7,6,8), in particular said first actuator (7), said second actuator (6) and said third actuator (8), or a combination thereof, in particular said control unit comprises a remote interface for an operator. 7. Cutting group (10) according to the preceding claims, in which a first group of pulleys (2,2 ') is provided, mounted on said support frame which define said first cutting plane (P1), and a second group of pulleys (4,4 ') mounted on said support arm (3) which define said second cutting plane (P2). Cutting unit (10) according to claim 7, wherein said first group of pulleys comprises said first pulley (2) and a first complementary pulley (2 '), and said second group of pulleys comprises said second pulley (4) and a second complementary pulley (4 '), in particular said first complementary pulley (2') is rotatably mounted idle on said support frame (1) in a fixed position around its own axis of rotation and spaced with respect to said first pulley ( 2), while said second pulley (4) and said second complementary pulley (4 ') are rotatably mounted on said support plate spaced apart from each other around respective rotation axes (14, 14'). 9. Cutting unit (10) according to the preceding claims, in which said support frame (1) is shaped to be mounted on a bearing element adapted to move said cutting unit (10), in particular said bearing element being selected among : an upright (40, 40 ') of a support portal (400), a handling arm (30), or a combination thereof. 10. Cutting machine (200) comprising a portal (400) having a first (40) and a second (40 ') upright and a crossbar (45) connected between said first (40) and second (40') upright, in wherein said portal (400) defines a housing opening (S) in which a piece (100) to be cut is arranged, and in which a respective cutting unit (10, 10 ') according to the preceding claims is arranged on said first (40) and second (40') upright.