ES2437139A2 - Device for tensioning the cutting wires in a multiwire machine for cutting slabs from blocks of stone material - Google Patents

Abstract

A device for tensioning the cutting wires (20) in a multiwire machine (1) for cutting slabs from blocks (B) of stone material. The device comprises one support element (30) including one annular seat (35) for housing a respective cutting wire (20) and actuating means acting on the support element (30) to promote the sliding thereof along a predetermined direction (Y), thus tensioning the respective cutting wire (20). The actuating means include at least one pneumatic cylinder (60, 60') with a rod (51, 51') having the free end (56, 56') operatively connected with the support element (30). A multiwire machine (1) including one or more of these devices.

Description

Device for tensioning the cutting wires in a multifilar machine to cut slabs from blocks of stone material. 5

Scope

The present invention can be applied, in general, in the technical sector of the processing of stone materials, and in particular has as its object a device for tensioning the cutting wires in a multifilar machine for cutting slabs of blocks of stone material, as well as a multifilar machine comprising such a device.

State of the art

15 Multifilar machines are known for cutting slabs from blocks of stone material, such as stone, marble, cement conglomerate and the like, which comprise a gantry frame on which diamond cutting wires are mounted. The latter, as is known, when moving along a substantially vertical direction penetrate the block of stone material, reducing it to plates. The thickness of the plates obtained from the cut is determined from the distance between two successive threads.

In a manner known per se, the threads are wound on one or more supporting elements thereof, generally drums or sets of adjacent pulleys suitable for rotating the threads themselves in order to favor penetration into the block. To allow such an action, the machine

Multifilar will comprise one or more suitable devices for tensioning the cutting wires.

Known devices of this type generally comprise actuators of the oleodynamic type that act on the support element, be it a drum or one or more pulleys, to aid sliding along a predetermined direction.

Such a known solution, although effective from a functional point of view, can be improved in terms of profitability, simplicity of maintenance and management and safety in case of breakage of one or more wires.

Summary of the invention

An objective of the present invention is to at least partially overcome the drawbacks indicated above, by making available a device for tensioning the cutting wires in a multifilar machine for cutting slabs from blocks of stone material of maximum efficiency and respective profitability.

Another object of the invention is to make available a device that allows to maintain relative versatility of use.

Another object of the invention is to make available a device that allows simple and quick maintenance.

Another object of the invention is to make available a device that is safe in case of breakage of one or more wires.

These objectives, as well as others that will become more clear in the following, are achieved by means of the device for tensioning the cutting wires in a multifilar machine for cutting slabs from blocks of stone material that has one or more of the features described and / or illustrated herein.

Conveniently, the device may comprise at least one support element that may include one or more

55 more annular seats to accommodate respective cutting wires. Such support element may include, or respectively be constituted by, one or more drums or one or more pulleys.

The device may also include pneumatic drive means, for example a pneumatic drive unit, which acts on said at least one support element to aid sliding along a predetermined direction, as well as to put in tension the cut threads wound on it. Advantageously, the device may also comprise a pneumatic circuit for bringing the pneumatic actuating means into fluid connection with means for supplying pressurized air inside it.

Preferably, the drive means may comprise one or more pneumatic cylinders with respective one or more rods having the free end functionally connected with said

less a support element.

In a preferred but not exclusive embodiment of the invention, the pneumatic circuit may include means or a unit for detecting a variation of the air flow inside it, for example, a variation of air flow.

In this way, it will be very simple and practical to detect the breakage of one or more threads, as well as making the device extremely safe for operators working on it.

10 Conveniently, the device may comprise blocking means that can be selectively activated by the detection means when a variation is detected inside the bypass circuit, for example the variation of air flow, to act on motor means of the multifilar machine , blocking the movement of the cutting threads.

15 Such a configuration makes the device even safer, since the blocking of the cutting wires will occur automatically when the flow variation in the branch circuit is detected.

In a preferred but not exclusive embodiment of the invention, regardless of the presence or passage of said means or units to detect a variation of the air flow inside the interior.

The pneumatic circuit, the drive means or drive units may comprise a pair of pneumatic cylinders and a connecting element having at least a first edge portion functionally connected with the at least one support element and at least a second portion of edge connected functionally with both rods of the pair of pneumatic cylinders in correspondence with respective connection zones.

25 Conveniently, such connection zones may be placed in at least a second edge portion of the connection element on the opposite side with respect to a median plane interposed between the connection zones themselves, which passes through the at least a second edge portion and substantially orthogonal to the plane defined by the at least one annular drum seat or by the at least one pulley.

In the present specification, with the term "midplane" interposed between two points, it is understood a plane interposed between the two points in a substantially central position, so that it is substantially equidistant between two points.

Advantageously, said at least a second edge portion of the connecting element may comprise a couple of second ends connected, each, functionally with the respective rod. The connection zones may be constituted by such ends.

Thanks to one or more of the above characteristics, the device is mechanically simpler, economical and simple and quick to maintain with respect to prior art devices.

On the other hand, a multifilar machine is provided for cutting stone blocks of stone material that includes the tensioning device that has one or more of the characteristics described and / or illustrated herein.

Advantageous embodiments of the invention are defined according to the dependent claims.

Brief description of the drawings

Other features and advantages of the invention will be apparent mainly in the light of the detailed description of a preferred, but not exclusive, embodiment of a tensioning device of the cutting wires in a multifilar machine for cutting slabs from blocks. of stone material according to the invention, illustrated by way of non-limiting example with the aid of the unit drawing sheets, in which:

Figure 1 is a schematic view of a multifilar machine 1 for cutting blocks B of stone material that includes a plurality of tensioning devices 50;

Figure 2 is a schematic view of a tensioning device 50 that includes a plurality of pulleys 30 mounted on the frame 10 of the multifilar machine 1, in which the frame 10 is represented with a dashed line;

Figure 3 is a schematic view of a single tensioning device 50;

Figure 4 is a schematic view of some particularities of the multifilar machine 1, in the state of rest;

Figure 5 is a schematic view of some particularities of the multifilar machine 1, in the working state;

Figure 6 is a schematic view of some particularities of the multifilar machine 1 when a cutting wire 20 is broken;

Figure 6a is an enlarged view of some particularities of Figure 6;

Figure 7 is a schematic view of some particularities of an alternative configuration of the multifilar machine 1, in the working state.

Detailed description of an example of preferred embodiment

With reference to the cited figures, a multifilar machine 1 for cutting slabs from blocks 15 B of stone material is described.

Machine 1 has several parts or elements equal to each other or in any case substantially similar. When not otherwise specified, such parts or elements will be described individually and / or indicated with a single number, it being understood that the characteristics described and / or illustrated are common to all other parts or elements that are the same or in any case substantially similar .

Said machine 1 comprises, in a manner known per se, a frame 10, a plurality of diamond cutting wires 20 and at least one pair, preferably a plurality, of support elements 31, which may be drums or a plurality of pulleys, mounted in the frame 10 for the support and movement of said

25 threads 20 cutting.

In a manner known per se, each support member 31 includes one or more annular seats to accommodate a respective cutting wire 20. The latter, in addition, are suitable for moving along the X direction, which may be substantially vertical, to penetrate block B and reduce it in plates.

To this end, motor means may be provided, generally indicated by reference number 40, which may be functionally connected to one or more of the support elements 31 to rotate them around their own axis, moving the cutting wires 20 into motion. . Thus, at all times, for each one of them an active branch 21 will be defined, facing the block B to be cut and

35 intended to penetrate it, and a return branch 22, opposite thereto.

Advantageously, the machine 1 may include a plurality of devices 50 for tensioning the cutting wires 20.

In general, each device 50 may include one or more support elements 30, which also have one

or more annular seats 35 for accommodating a respective cutting wire 20, and pneumatic actuating means acting on them to aid movement along a longitudinal direction Y.

45 Conveniently, each support member 30 may include one or more drums or one or more pulleys.

In a preferred but not exclusive embodiment of the invention, illustrated in Figures 2 and 3, the drive means may include a pair of guiding elements 51, 51 'functionally connected to a support element 30.

In a preferred but not exclusive embodiment, the support element may include, or respectively be constituted by, a pulley 30 having one or more annular seats 35 to accommodate respective cutting threads 20. It is understood, however, that the device may equivalently include a drum without thereby departing from the scope of protection of the invention defined in the

55 attached claims.

The guiding elements 51, 51 ', in addition, may include, or respectively be constituted by, stems mounted on the multifilar machine 1 in order to slide along predetermined sliding directions Y', Y ", which may be parallel between yes. In this way, the rods 51, 51 ’will guide the pulley 30 along the Y direction, which can be parallel to the Y’, Y ”directions.

In particular, the mounting of the rods 51, 51 ’on the machine 1 may occur so that the directions Y, Y’, Y ”are substantially orthogonal with respect to the direction X of movement of the cutting threads 20. Alternatively, the rods 51, 51 ’will be mounted on the machine 1 so that

65 the Y, Y ’, Y” directions are substantially inclined with respect to the X direction.

The mutual operational connection between the rods 51, 51 ’and the pulley 30 can be guaranteed by a convenient connection element 52.

In particular, the connecting element 52 may comprise, or respectively be constituted by, a pair 5 of facing plates 53, 53 ′, arranged in the opposite part to the pulley 30.

Each plate 53 may have a first edge portion 54 functionally connected with the pulley 30 and a second edge portion 54 'opposite the first, functionally connected with the corresponding ends 56, 56' of both stems 51, 51 'of the pair of pneumatic cylinders 60, 60 'in correspondence with respective connection zones 55, 55'.

Advantageously, in order to guide the pulley 30 as much as possible in its sliding along the Y direction, the connection zones 55, 55 'may be placed in the second edge portion 54' of the connection element 52 on the side opposite with respect to an average plane πM interposed between the zones of

15 connection 55, 55 ’, which passes through the second edge portion 54’ and substantially orthogonal to the plane π defined by the at least one annular seat 35 of the pulley 30 and / or the respective annular seat 35.

It is further understood that under the usual working conditions, the plane π defined by the at least one annular seat 35 may be substantially vertical, while the means πM may be substantially horizontal.

Thanks to such a configuration, subsequent guiding means will not be required to guide the sliding of the pulley 30 along the Y direction. In other words, the rods 51, 51 'will define both drive means and some guiding means for the support element 30.

25 It is understood that the connection zones 55, 55 ’and / or the associated rods 51, 51’ may be superimposed on each other or mutually displaced.

Conveniently, the connecting zones 55, 55 'may be mutually superimposed so that the associated rods 51, 51' define a plane π 'substantially parallel or coincident with the plane π defined by said at least one annular seat 35 of the pulley 30 and / or the associated annular seat 35.

Conveniently, the second edge portion 54 ’of the connection element 52 may comprise a pair of connected ends, each functionally with the respective rod 51, 51’. Connection zones

35 55, 55 ’may be constituted by such extremes.

Preferably, in order to optimize the mechanical stresses of the system, the middle plane πM may coincide with the plane of symmetry of the first and second edge portions 54, 54 ’.

Conveniently, in addition, the second edge portion 54 ’may comprise a pair of opposite ends 55, 55’ defining the aforementioned connection zones.

In a preferred but not exclusive embodiment of the invention, illustrated in Figures 2 and 3, the connecting element 52 may be presented in the form of an isosceles triangle, with a vertex

45 defining the first edge portion 54 and the opposite edge defining the second edge portion 54 ’. In addition, the ends of the latter may define connection zones 55, 55 ’.

In such a case, the middle plane πM will define the plane of symmetry of the connection element 52 substantially orthogonal to the plane π defined by the pulley 30 and / or by the associated annular seat 35.

Here, the term "isosceles triangle" and its derivatives means a triangle that has at least two equal sides to each other. Therefore, an equilateral triangle is an isosceles triangle for the purposes of the present specification.

Preferably, the actuation means may include, or respectively, be constituted by, a pair of pneumatic cylinders 60, 60 ', which may be in fluid connection with means for supplying pressurized air within them, for example a compressor 70, by means of the pneumatic circuit 71.

Stems 51, 51 ’may present ends 57, 57’ functionally coupled with pneumatic cylinders 60, 60 ’. In particular, each pneumatic cylinder 60, 60 'may include a sliding piston 61 included therein between a start position, illustrated in Figure 4, and a limit switch, illustrated in Figure 6. Each piston 61 , 61 'may be functionally connected to the respective rod 51, 51' corresponding to the ends 57, 57 '.

Each piston 61 may divide the associated cylinder 60 into two compartments 62 ', 62 "of variable volume, preferably adjacent to each other.

Preferably, the rods 51, 51 'will have the same dimensions, and in particular the same length. 5 Conveniently, in addition, the pistons 61 functionally connected to the rods 51, 51 ’may have the same stroke inside the respective cylinder 60, 60’.

Advantageously, the pneumatic cylinders 60, 60 'may be connected to each other in parallel, as well as the air flow inside is the same. Preferably, moreover, the pneumatic cylinders 60, 60 ’will have the same dimensions, so that the force exerted on the pulley 30 is the same.

Conveniently, the pneumatic circuit 71 may comprise valve means 72 for regulating the entry of air into the cylinders 60, 60 ’.

15 The valve means 72 may divert the air flow in two branches 73 ', 73 "of circuit 71, which may connect the compressor 70 to the fluid connection respectively with chambers 62' and 62".

In particular, in the first position illustrated in Figure 4, which corresponds to the state of rest of the multifilar machine 1, the valve means 72 will connect the compressor 70 with the chamber 62 ", so that the piston 61 remains in the position Start of career.

In the second position illustrated in Figure 5, which corresponds to the working state of the multi-machine 1, the valve means 72 will connect the compressor 70 with the chamber 62 ', so that the air blown from the compressor 70 into the interior of the cylinders 60, 60 'determine the sliding of the stems

25 51, 51 ’along the Y’, Y ”directions, with the consequent sliding of the pulley 30 connected to them and the tensioning of the cutting threads 20 inserted in the seats 35.

Advantageously, circuit 71 may include means for detecting a variation of the air flow inside it, for example a variation of air flow.

Conveniently, the means for detecting a variation of the flow inside the circuit 71 may include a flow switch 75. In addition, the means for detecting a variation within the circuit 71 may include a concave zone 76 made in each cylinder 60, 60 '.

35 The concave zone 76 may have dimensions such that, when the piston 61 reaches the end of the stroke, the two chambers 62 ', 62 "of each cylinder 60 are in mutual fluid communication. The branch 73 "of the circuit 71 has an end 74 connected to the bottom of the concave zone 76, as can be seen in Figure 6a.

When a thread 20 breaks, the pressure present in the chamber 62 ’pushes the piston 61 and, consequently, the pulley 30 connected thereto. The unexpected sliding of the pulley will allow an operator to visually observe the breakage, so that he can lock the machine to avoid jams and / or breakage.

45 When the wire 20 is broken, as illustrated in Figure 6, the fluidic communication that is created between the chambers 62 ’, 62 ″ creates a flow variation inside the circuit, which can be detected by the flow switch 75.

Conveniently, blocking means may be provided, for example a microprocessor logic unit 80, connected to the flow switch 75 and which can be connected by it when a variation of air flow is detected inside the circuit 71 to act on the means motors 40 and block the movement of the cutting wires 20, as you can see in Figure 6.

In this way, the device according to the invention is extremely safe in case of breakage of the threads 55 20, since the blocking of the machine will occur completely automatically.

The microprocessor logic unit 80 may also activate visual and / or acoustic warning means 81.

A rapid discharge valve 77 may also be provided, which will allow the circuit 71 to be rapidly discharged if necessary.

Advantageously, all the pneumatic cylinders of the tensioning devices 50 mounted on the machine 1 may be in fluid connection with each other in parallel with the compressor 70.

65 An alternative configuration of the invention is illustrated in Figure 7, in which the device 50 includes a single pneumatic cylinder 60 functionally connected with the support element 30, which may be constituted by one or more drums or one or more pulleys .

It is understood that the support element 30 may include guiding means, for example one or more

5 guide stems 58, 58 'intended to slide slidably in the frame 10 of the multifilar machine 1 along respective directions Y', Y "substantially parallel to the sliding direction Y of the stem 51 of the single pneumatic cylinder 60 , without departing, therefore, from the scope of protection of the appended claims.

10 The pneumatic cylinder 60 may be in fluid connection with the pressurized air source 70 by the pneumatic circuit 71.

In a preferred but not exclusive embodiment, such an embodiment of the invention may include detection means 75 and / or blocking means 80, which may be

15 preferably in all analogues and operating in the same manner described above for the embodiment illustrated in Figures 4 to 6a.

In view of the foregoing, it is understood that the tensioning device and the multifilar machine according to the invention achieve the previously established objectives.

The device according to the invention is simpler, cheaper and simple and quick to maintain with respect to the devices of the prior art.

In addition, it will be safer in case of thread breakage, since in this case the stems 51, 51 ’25 will go to the

25 end of the race, pushing out the associated pulley 30. In addition, blocking means 80 and / or alert means 81 will be activated.

The tensioning device and the multifilar machine according to the invention are susceptible of numerous modifications and variants, all of which fall within the concept of the invention expressed in the

30 appended claims. All details may be replaced by other technically equivalent elements, and the materials may vary according to requirements, without departing from the scope of protection of the invention.

Claims (7)

1. Device for tensioning the cutting wires (20) in a multifilar machine (1) to cut slabs from of blocks (B) of stone material, the device being characterized in that it comprises: 5

-

at least one support element (30) that includes at least one annular seat (35) for a respective cutting wire (20);

-

actuation means acting on said at least one support element (30) for

10 favoring the sliding thereof along a predetermined direction (Y), thereby tensioning the respective cutting wire (20), said drive means including a pair of pneumatic cylinders (60, 60 ') with a respective torque of rods (51, 51 ') having a respective free end (56, 56') functionally connected with said at least one support element (30), 15 - a connection element (52) having a first edge portion (54) functionally connected with said at least one support element (30) and at least a second edge portion (54 ') functionally connected with said both rods (51, 51 ') in correspondence with respective connection zones (55, 55'), 20 characterized in that said connection zones (55, 55 ') are placed in said at least a second edge portion (54') of said connection element (52) on opposite sides relative to a median plane (πM) interposed between said connection zones (55, 55 ') and substantially orthogonal to the plane (π) defined by said at least one annular seat (35). Device according to claim 1, characterized in that said connection zones (55, 55 ') are mutually superimposed, so that said rods (51, 51') define a plane (π ') substantially parallel or coincident with said plane (π) defined by said at least one annular seat (35). Device according to claim 1 or 2, characterized in that said middle plane (TM) coincides with the plane of symmetry of said connecting element (52) passing through said first edge portion (54) and of said at least a second edge portion (54 ’). Device according to claim 1, 2 or 3, characterized in that said at least a second portion of edge (54 ’) includes a pair of opposite ends (55, 55’) that define said connection zones. 35 Device according to claim 3 and 4, characterized in that said connecting element (52) has a substantially isosceles triangle shape with a vertex defining said first edge portion (54) and defining the opposite edge said at least a second edge portion (54 ’).

Device according to one or more of the preceding claims, characterized in that it further comprises a pneumatic circuit (71) for connecting said fluid to at least one pneumatic cylinder (60, 60 ') and means (70) for supplying pressure inside it, said circuit (71) including means (75) for detecting a variation of the air flow inside it.

Device according to the preceding claims, characterized in that said at least one pneumatic cylinder (60, 60 ') internally includes a piston (61, 61') functionally connected with said at least one rod (51, 51 ') to move from sliding way between a start position and an end position, at least one pneumatic cylinder (60, 60 ') and said pneumatic circuit (71) being mutually configured so that said detection means (75) detect a variation of the air flow in the

50 circuit (71) when said piston (61, 61 ’) is near the limit position. Device according to claim 6 or 7, characterized in that the multifilar machine (1) includes motor means (40) for moving the cutting wires (20), the device including locking means (80) that can be selectively activated by said detection means (75) upon detecting a variation in the flow of 55 air in the circuit (71) and which are capable of acting on motor means (40) to automatically block the movement of the cutting wires (20). 9. Multifilar machine for cutting in block plates (B) of stone material, characterized in that it comprises a frame (10) and a plurality of cutting threads (20), the machine also including at least A device (50) for tensioning the cutting wires (20) according to one or more of the preceding claims. 10. Multifilar machine according to claim 9, wherein all the pneumatic cylinders (60, 60 ’) are in parallel fluid connection with means (70) for supplying pressurized air inside them.