DESCRIPTION

"Device for breaking blocks of stone, marble, granite, concrete and similar, apparatus and method thereof"

[0001] This following invention relates to a device for breaking blocks of stone, marble, granite, concrete and similar, an apparatus comprising said device and the method thereof .

[0002] In particular, having extracted from quarries blocks of stone, marble, granite, concrete and similar, it is necessary to break or split such blocks into smaller units to allow easy transportation and subsequent cutting and superficial finish machining.

[0003] Various devices and methods for breaking blocks of stone, marble, granite, concrete and similar are known. [0004] For example, it is known to use explosive means that are inserted into dedicated holes in the blocks.

[0005] This practice implies safety problems in handling the explosives and above all it does not guarantee control over the breaking operation. For example, it is almost impossible to cut the block along a specific fracture plane, for example corresponding to a vein in the block, by using explosives.

[0006] It is also known to use tools such as wedges or cones that are forcedly inserted into openings made previously in the blocks. Such operation is, however,

slow and requires the performing of holes or openings of large dimensions in the blocks.

[0007] The solutions of the known art therefore present several drawbacks and limitations, because they do not guarantee a precise cut along a desired fracture plane and they often require extremely long times .

[0008] The aim of this invention is to make a device that resolves the cited drawbacks of the known art .

[0009] Such drawbacks and limitations are resolved by a device in agreement with claim 1, by apparatus according to claim 22 and by a method in agreement with claim 24.

[0010] Other embodiments of the invention are described in the following claims .

[0011] Further characteristics and advantages of this invention will be further evident in the description that follows of its preferred and non-limiting embodiments of the finding, wherein:

[0012] figure 1 illustrates a perspective view of an assembly configuration of a device according to one embodiment of the present invention;

[0013] figure 2 illustrates a perspective view in separate parts of certain components of the device of figure 1;

[0014] figure 3 illustrates a section view of the device of figure 1 in assembly configuration; [0015] figure 4 illustrates a schematic view of apparatus

for breaking blocks of stone, marble, granite, concrete and similar according to one embodiment of this invention.

[0016] The elements or parts of elements in common between the embodiments described below will be indicated with the same numbers .

[0017] With reference to the aforesaid figures, 4 indicates a device for breaking blocks of stone, marble, granite, concrete and similar 8. [0018] In particular, the device 4 for breaking blocks of stone 8 comprises a body 12 that extends along a prevalently axial direction X-X from a first to a second axial extremity 13 , 14 ; for example said body is made in the form of a cylindrical bar with an axis X-X. The body comprises a feed pipe 16 suited to receiving a pressurised fluid through at least one inlet 20 and to dispensing such pressurised fluid through at least one outlet 24. [0019] Preferably, said body 12 is a cylindrical body with an axis X-X, internally crossed by the feed pipe 16.

[0020] According to one embodiment, the inlet 20 is arranged in correspondence with one axial extremity and the outlet 24 is arranged in correspondence with a centre line of the body. [0021] According to one embodiment, the outlet 24 of the

body is made by means of at least one radial hole 26. Preferably, the radial hole 26 crosses the body along a diameter of the body so that the fluid can expand outside of the body; the body should preferably comprise two radial holes 26 opposite one another. Preferably said at least one radial hole is arranged on the axial centre line of the body 12.

[0022] Preferably the body comprises a second outlet 28, arranged on the second axial extremity 14 ; the second outlet can be hermetically closed with a/ dedicated plug or can be opened to allow the connection of the device with a further device 4 connected serially with the first in order to be fed by the same pressurised fluid. [0023] The device 4 advantageously comprises an expanding element 40, that is preferably elastically expanding, fitted around said body 12, so as to form with said body an expansion chamber 44 fluidly connected with said at least one outlet 24, 26 of the body 12. [0024] The expanding element 40 is suited to passing, under the action of the pressurised fluid, from an undeformed configuration to an expanded configuration to an expanded configuration in which it increases in volume, expanding in a direction radial to the axis X-X (figure 3) . Radial direction means a direction perpendicular to the axis X- X.

[0025] The device 4 comprises fixing and holding means 50, preferably arranged in correspondence with the axial extremities 13,14 of the body 12 and suited to joining the expanding element 40 to the body 12 and to making an airtight seal of the expansion chamber 44. In other words, the fixing and holding means 50 hermetically close the expansion chamber 44 so that the pressurised fluid is channelled through the inlet 20 and comes out through the outlet 24,26 without being able to come out of the extremities of the device in order to be able to cause the expansion of the expanding element 40. [0026] In the arrangement in which the second outlet 28 of the device is open, the pressurised fluid is able to come out of the device and be sent to a further device 4 arranged serially with the first.

[0027] The elastically expanding element 40 is a tube in polymeric material, preferably it is a polyurethane tube. [0028] The fixing and holding means 50 comprise at least one socket 60 fitted, in correspondence with said axial extremities 13,14 onto the expanding element 40 so as to join the expanding element on to the extremities 13,14 of the body 12. In particular, the sockets 60 fitted in correspondence with the extremities onto the expanding element 40, radially pinch the expanding element 40 so as to prevent its expansion in correspondence with the axial

extremities 13 , 14 of the body 12.

[0029] The sockets 60 are associated to the axial extremities 13 , 14 by means of a form fit suited to preventing the axial detachment of the socket 60 from the extremities 13 , 14.

[0030] For example the form fit is a threaded fit, i.e. the body 12 comprises threaded portions 64 in correspondence with said extremities 13,14 and the sockets screw into said threaded portions 64 so as to be joined axially to the body 12.

[0031] According to one possible embodiment, the device 4 comprises at least one bushing 70 solidly associated to an extremity 13 , 14 of said body 12 and positioned between said body 12 and the expanding element 40. [0032] Preferably the bushings 70 are screwed to the axial extremities 13, 14 of the body 12.

[0033] The bushings 70 comprise at least one slot 74 passing through the bushing 70; preferably the slots extend parallel to the axial direction X-X. [0034] Preferably the fixing and holding means 50 comprise a filling element 80 arranged between the bushing 70 and the expanding element 40 so as to block the rotation of the bushing 70, the body 12 and the expanding element 40 and to make an airtight seal of said expansion chamber 44.

[0035] For example, said filling element 80 is made by means of a cast of melted polymeric material, inserted into said axial extremities 13 , 14 of the device so as to fill the gaps between the bushing 70, the body 12 and the expanding element 40. Preferably said filling element 80 is a polyurethane .

[0036] The filling element 80 guarantees the airtight seal of the expansion chamber 44 and also joins the bushings 70 with the axial extremities 13,14. In particular, the slots 74, after having been filled by the filling element 80, prevent any relative rotation between the bushings 70 and the body 12.

[0037] The socket 60 comprises at least one axial opening 84 suited to allowing the passage of said axial extremities 13 , 14 and therefore the fluid connection of the axial extremities for example with a delivery of pressurised fluid or with a further device 4 to be connected serially. [0038] For example, the device 4 comprises at least one retainer 88 screwed onto said axial extremities 13,14 against the socket 60, so as to prevent the extraction of the socket from the axial extremities 13,14. [0039] The retainer 88 comprises a hole 92 in fluid connection with at least one of said inlet and/or outlet openings 20,24,28 of the body 12.

[0040] Preferably, the retainer 88 comprises an attachment portion 96 suited to allowing the connection of the feed pipe 16 of the body 12 with a pressurised fluid delivery or introduction pipe. [0041] The present invention also relates to apparatus 100 for breaking blocks of stone 8 comprising at least one device 4 as described and means for sending a pressurised fluid into said at least one device 4, such as pumps or compressors for sending a fluid or compressed air to the devices 4.

[0042] Preferably, the apparatus 100 comprises a plurality of devices 4 that are fluidly joined to one another so as to be fed by the same pressurised fluid and to be able to expand simultaneously and in the same way. [0043] The operation of a device according to the invention and the method for breaking a block of stone thereof will now be described.

[0044] In particular to break a block of stone 8, at least one insertion hole 110 is previously made in the block of stone 8, in correspondence with a desired fracture plane 114 that one intends to obtain on the block of stone 8. The insertion holes must be aligned with one another along the theoretical fracture plane 114 (figure 4) so that a combined thrust action of the devices 4 may cause a crack in the block of stone 8 exactly in correspondence

with the chosen fracture plane 114.

[0045] The insertion holes 110 must have a size such as to allow the insertion of the device 4 in a standby or undeformed configuration. If the block of stone 8 has particularly extensive dimensions it is possible to insert into each insertion hole 110 a plurality of devices 4 connected in series with one another so as to simultaneously exert a thrust action inside the same insertion hole 110 along the whole extension of the hole. [0046] Then into said insertion hole 110 at least one device 4 is fitted suited to passing from a standby configuration, wherein it is passing through said hole 110, to an expanded configuration wherein it increases in volume so as to exert a thrust action inside said insertion hole 110.

[0047] Pressurised fluid is sent into the devices 4 so as to cause the expansion of the expanding element 40 and therefore the propagation of a crack that leads to the fracture of the block of stone. [0048] In particular the fluid enters the feed pipe through the inlet 20, it propagates in the feed pipe and comes out in the expansion chamber through the outlet 24. The fluid presses against the inner wall of the expanding element 40 which starts to expand radially. In correspondence with the extremities 13 , 14 , the expanding

element 40 cannot dilate due to the presence of the sockets 60 that prevent any radial dilation thereof. After reaching a sufficiently high pressure value, the devices 4 are able to cause the fracture of the block of stone 8 along the desired fracture plane 114.

[0049] Preferably, to perform a precise and controlled fracture of the block of stone 8 the sending of the pressurised fluid into the device 4 takes place in subsequent phases . [0050] In particular, subsequent increases are made in the pressure of the fluid sent into the devices 4, said increases being alternated with adjustment phases in which the pressure of the fluid remains constant. In this way a state of uniform stress is caused in correspondence with all the insertion holes 110 along the fracture plane 114, so as to make a controlled fracture of the block 8 along the desired fracture plane 114. [0051] As can be illustrated by the description, the device and the method according to the invention makes it possible to overcome the drawbacks presented in the known art.

[0052] In particular, the device according to the present invention makes it possible to perform the breakage of a block of stone according to a precise fracture plane, for example corresponding with a vein in the block.

[0053] In fact, the device is able to exert a controlled expansion force with extreme precision so as to perform the breakage of the block in a controlled and non- impulsive manner. [0054] The device does not envisage the use of explosive materials that in addition to implying risks for the safety of the operator, do not guarantee precision and uniformity of the cut of the stone. [0055] The device according to the invention is able to perform breakage in relatively rapid timeframes that are always controlled by the operator.

[0056] The device can be reused for subsequent and repeated cutting operations . [0057] The device can easily be used on blocks of stone having even very different dimensions. In fact, if the block has a considerable depth it is possible to fluidly connect to one another several devices that are inserted serially with one another in the same insertion hole. [0058] Thanks to the device in agreement with the present invention, it is possible to make the breakage of blocks of stone by previously performing simple, for example cylindrical) holes in the same blocks.

[0059] Advantageously said cylindrical holes, suited to allowing the insertion of expansion devices, have a reduced diameter so that the same holes constitute

geometrical elements that concentrate the shear stresses caused by the expansion of the devices and that therefore facilitate the propagation of the cracks along the fracture plane of the block of stone. [0060] The cutting method is therefore simple to perform and can be easily controlled by an operator. [0061] A man skilled in the art, in order to satisfy contingent and specific requirements, will be able to make various modifications and variants to the devices, apparatus and methods described above, all of which being within the scope of this invention as defined by the following claims .