The present invention relates to a nailing machine, particularly for assembling flanges of wooden spools for winding electrical cables, steel cables, ropes, fiber optic cables or wire-like elements in general according to the preamble of claim 1. Such a machine is disclosed by
The process for the production of these flanges provides for a step of composing the two layers of strips, a step of assembly by nailing the strips of the two layers to each other and a step of cutting the two assembled layers so as to obtain the circular plan shape of the flanges.
Flanges of this type are manufactured by using nailing machines that comprise substantially: a station for composing the flange to be assembled, a nailing station and a resting and sliding surface, which is usually horizontal and is extended from the composition station to the nailing station and along which the two layers of strips that compose the flange to be assembled are moved.
At the nailing station there is at least one row of nailing clamps, generally two rows of nailing clamps. The row or rows of nailing clamps are oriented at right angles to the direction along which the flange to be assembled is moved from the composition station to the nailing station.
Before nailing, the strips of the two layers are compacted by means of adapted compaction elements, which are supported by a structure that can rotate about a vertical axis which, when the flange to be assembled is in the nailing station, coincides with the center of the flange to be assembled. The assembly of the two layers of strips that compose the flange to be assembled is performed by operating a plurality of times the nailing clamps and by rotating through angles of preset breadth the flange to be assembled about its own axis while the compaction elements maintain their action on the strips of the two layers.
Substantially, upon each operation of the nailing clamps, the machine applies two rows of nails that are mutually parallel and are oriented transversely to the advancement direction along which the flange has been moved from the composition station to the nailing station and after each operation the flange is rotated about its own axis through an angle of preset breadth. When the flange has been rotated in total through 180° about its own axis, the assembly method is complete.
A few nailing sequences are necessary in order to achieve the fixing of all the strips of one layer to the strips of the other layer and therefore, during these nailing sequences, it is necessary to maintain the strip compaction action on the part of the compaction elements. As a consequence of this requirement, it is necessary to rotate the compaction elements and the structure that supports them together with the flange to be assembled.
The rotation of the supporting structure and of the compaction elements is a source of problems and drawbacks.
This structure is in fact necessarily bulky and therefore its rotation is difficult.
Furthermore, the locking elements are difficult to adjust in order to be adapted to be used for the manufacture of flanges of various diameters.
Another drawback, which arises from the space occupation of the structure used to turn the flange about its own axis, is constituted by the need to also provide the framework that supports the large nailing clamps.
These problems and drawbacks affect the overall costs of machines of this type, which are high.
Furthermore, these machines require long times in order to change the format of the flanges being manufactured.
The aim of the present invention is to solve the problems and obviate the drawbacks described above, by providing a nailing machine, particularly for assembling flanges of wooden spools for winding electrical cables, steel cables, ropes, fiber optic cables or wire-like elements in general, that allows to reduce the time required to assemble the flanges and is simpler than machines of the known type both in terms of construction and in terms of actuation.
Within this aim, an object of the invention is to provide a machine that does not require to maintain the action of compaction of the strips that compose the flange during rotation about its own axis in order to complete the nailing operation.
Another object of the invention is to provide a machine that can be automated in a relatively simple manner in order to allow to pass from one flange format to another in much shorter times than currently commercially available machines.
Another object of the invention is to provide a machine that can be manufactured at competitive costs.
A further object of the invention is to provide a machine that ensures high safety and reliability in operation.
This aim, as well as these and other objects that will become better apparent hereinafter, are achieved by a nailing machine, particularly for assembling flanges of wooden spools for winding electrical cables, steel cables, ropes, fiber optic cables or wire-like elements in general, comprising:
Further characteristics and advantages of the invention will become better apparent from the description of a preferred but not exclusive embodiment of the machine according to the invention, illustrated by way of nonlimiting example in the accompanying drawings, wherein:
With reference to the figures, the machine according to the invention, designated generally by the reference numeral 1, comprises a station 2 for composing a spool flange to be assembled 3 (hereinafter simply "flange 3"), a nailing station 4, means 5 for supporting the flange 3 on a substantially horizontal plane, and means 6 for the advancement of the flange 3 from the composition station 2 to the nailing station 4 along an advancement direction, designated by the arrow 7.
The flange 3 is composed, in a per se known manner, by superimposing two layers of strips 8a, 8b arranged side by side, with the strips 8a of one layer oriented at right angles to the advancement direction 7 and the strips 8b of the other layer oriented parallel to the advancement direction 7.
The machine according to the invention is provided with means 9 for compacting the strips 8a, 8be that compose these two layers, respectively along a direction that is parallel to the advancement direction 7 and along a direction that is perpendicular to the advancement direction 7 or along directions that are parallel to the direction of side-by-side arrangement of the strips 8a, 8b in the corresponding layer.
At the nailing station 4 there are nailing means 10 and means 11 for rotating the flange 3 about its own axis, which is oriented substantially vertically.
According to the invention, the nailing means 10 comprise at least two rows 12a, 12b, 13a, 13b of nailing clamps 14, which are oriented at right angles to each other, respectively at least one first row 12a, 12b of nailing clamps 14, which is oriented parallel to the advancement direction 7, and at least one second row 13a, 13b of nailing clamps 14, which is oriented at right angles to the advancement direction 7.
More particularly, the at least two rows 12a, 12b, 13a, 13b of nailing clamps 14 are arranged in a cross-like pattern that is centered on a main vertical axis 15 at which the axis of the flange 3 is arranged when said flange is placed at the nailing station 4.
The nailing machine according to the invention comprises a main supporting structure 16, which is provided with ground resting feet, and the supporting means 5 are constituted by bars 17 that are fixed to the main supporting structure 16 and define a substantially horizontal resting and sliding surface 18 for the flanges 3 to be assembled. The bars 17 extend from the composition station 2 to the nailing station 4.
The advancement means 6 comprise a first pusher 19, constituted by a flap, which is fixed transversely to a pair of chains 20 (only one of which is visible in
Substantially, the chains 20 to which the first pusher 19 is fixed are arranged on substantially vertical planes that are parallel to the advancement direction 7, so that when the first pusher 19 is along the upper portion of the chains 20 it protrudes upwardly from the resting and sliding surface 18, while when it is along the lower portion of the chains 20 it is arranged below the resting and sliding surface 18, so as to not interfere with the flange 3 during its composition while the first pusher 19 is returned from the nailing station 4 to the composition station 2.
The chains 20 to which the first pusher 19 is fixed engage pinions 21, the axes of which are arranged horizontally and are oriented at right angles to the advancement direction 7. One of the pinions 21 is connected to the output shaft of a corresponding gearmotor, not visible in the figures, which can be operated in order to actuate the chains 20 to which the first pusher 19 is fixed.
It should be noted that in the various accompanying figures the chains of the chain connections that are provided in the machine according to the invention are shown schematically, in some cases without showing in details the links that compose them, in other cases by showing in detail only some of the links that compose them and in further cases simply with a dot-and-dash line. Moreover, it should be noted that in some chain connections the chains have been omitted for the sake of simplicity and greater clarity.
The compaction means 9 comprise: the first pusher 19, a second pusher 23, which is arranged at the nailing station 4 and can move from an inactive position, in which it is arranged below the resting and sliding surface 18 so as to not interfere with the flange 3, as shown for example in
The compaction means 9 also comprise a third pusher 24, which is arranged at the nailing station 4 and is adapted to protrude above the resting and sliding surface 18, and a fourth pusher 25, which also is arranged at the nailing station 4 and is adapted to protrude above the resting and sliding surface 18. The third pusher 24 and the fourth pusher 25 are mutually opposite along a direction that is perpendicular to the advancement direction 7 and can move on command toward or away from each other.
More particularly, the second pusher 23 also is constituted by a flap and is fixed to a corresponding pair of chains 26, which are arranged on vertical planes parallel to the bars 17. The second pusher 23 can engage the side of the flange 3 that is opposite with respect to the side engaged by the first pusher 19 when the flange 3 is arranged at the nailing station 4. The second pusher 23, by way of the actuation of the chains 23 to which it is fixed, can be moved above the resting and sliding surface 18, as shown for example in
Substantially, the chains 26 to which the second pusher 23 is fixed are arranged downstream of the chains 20 to which the first pusher 19 is fixed and engage corresponding pinions 27, the axes of which are arranged horizontally and are oriented at right angles to the advancement direction 7. One of the pinions 27 is connected to the output shaft of a corresponding gearmotor, not shown in the figures, which can be actuated in order to actuate the chains 26 to which the second pusher 23 is fixed.
The third pusher 24 is constituted again by a flap and is fixed to a corresponding pair of chains 29, which are arranged, on vertical planes, at right angles to the bars 17. The third pusher 24 can engage one of the sides of the flange 3 that are parallel to the advancement direction 7, i.e., perpendicular to the sides with which they engage the first pusher 19 and the second pusher 23, when the flange 3 is arranged at the nailing station 4. The third pusher 24, by way of the actuation of the chains 29 to which it is fixed, can be moved above the resting and sliding surface 18, as shown for example in
Substantially, the chains 29 to which the third pusher 24 is fixed are arranged laterally to a vertical central plane of the machine that is parallel to the advancement direction 7 and passes through the main axis 15 and engage corresponding pinions 30, the axes of which are arranged horizontally and are oriented parallel to the advancement direction 7. One of the pinions 30 is connected to the output shaft of a corresponding gearmotor 31, which can be actuated in order to actuate the chains 29 to which the third pusher 24 is fixed.
In turn, the fourth pusher 25 is constituted by a flap and is fixed to a corresponding pair of chains 32 arranged on vertical planes at right angles to the bars 17. The fourth pusher 25 can engage the side of flange 3 that is opposite with respect to the side that the third pusher 24 engages when the flange 3 is arranged at the nailing station 4. The fourth pusher 25, by way of the actuation of the chains 32 to which it is fixed, can be moved above the resting and sliding surface 18, as shown for example in
The chains 32 to which the fourth pusher 25 is fixed are arranged laterally to the vertical central plane of the machine on the opposite side with respect to the chains 29 of the third pusher 24 and engage corresponding pinions 33, the axes of which are arranged horizontally and are oriented parallel to the advancement direction 7. One of the pinions 33 is connected to the output shaft of a corresponding gearmotor 34, which can be actuated in order to actuate the chains to which the fourth pusher 25 is fixed.
The pinions 27, 30, 33 with which the chains 26, 29, 32 engage are supported by corresponding supporting structures 35, 36, 37, which are fixed to the main supporting structure 16, to which side walls 35a, 36a, 37a are fixed which, with their upper side, cooperate with the upper side of the bars 17 in defining the resting and sliding surface 18. The pair of pinions 21 with which the chains 20 of the first pusher 19 engage, proximate the nailing station 4, also is supported by a corresponding supporting structure 38, which is fixed to the main supporting structure 16 and is provided with side walls 38a which, with their upper side, cooperate with the upper side of the bars 17 in defining the resting and sliding surface 18.
Conveniently, at least one between the first pusher 19 and the second pusher 23 has, on its face intended to engage the flange 3, a first protruding tooth 39 which is arranged in a manner adapted to engage one layer of the two layers of strips 8a, 8b that compose the flange 3. In the illustrated embodiment, there is a first tooth 39, which is fixed to the second pusher 23 and is intended to engage the strips 8a of the lower layer that compose the flange 3.
Likewise, at least one between the third pusher 24 and the fourth pusher 25 has, on its face intended to engage the flange 3, a second protruding tooth 40, which is arranged in a manner adapted to engage with the other layer of the two layers of strips 8a, 8b that compose the flange 3. In the illustrated embodiment there is a second tooth 40, which is fixed to the fourth pusher 25 and is intended to engage the strips 8b of the upper layer that compose the flange 3.
Conveniently, the machine according to the invention comprises riveters which are arranged in the nailing station 4 below the nailing clamps 14.
These riveters are constituted by four riveters 41, 42, 43, 44, which, in a manner similar to the rows 12a, 12b and 13a, 13b of nailing clamps 14, are arranged in a cross-like pattern radially with respect to the main axis 15.
Each one of the riveters 41, 42, 43, 44 is constituted by a plate that is arranged horizontally and preferably has, on its upper face, a plurality of knurlings so as to increase adhesion to the tip of the nails. Each riveter is arranged between the side walls 38a, 35a, 36a, 37a that support the pinions 21, 27, 30, 33 and externally to which the chains 20, 26, 29, 32 are arranged.
Preferably each one of the riveters 41, 42, 43, 44 can move on command vertically and parallel to the direction along which the row or rows 12a, 12b, 13a, 13b of nailing clamps 14, below which it is arranged, is extended.
More particularly, the two riveters 43, 44 arranged between the side walls 36a and between the side walls 37a, which support respectively the pinions 30, 33 of the chains 29, 32 of the third pusher 24 and of the fourth pusher 25, are mutually aligned along a direction that is perpendicular to the advancement direction 7 and can move on command vertically and at right angles to the advancement direction 7, while the other two riveters 41, 42, which are arranged between the side walls 38a and between the side walls 35a, which support respectively the pinions 21 of the chains 20 of the first pusher 19 and the pinions 27 of the chains 26 of the second pusher 23, are mutually aligned along a direction that is parallel to the advancement direction 7, more precisely along the central axis of the machine, and can move on command vertically and parallel to the advancement direction 7.
This movement of the riveters 41, 42, 43, 44 is achieved by connecting each riveter to a corresponding gearmotor via a crank connection 60.
The gearmotor 45 is fixed, by means of its body, to the supporting structure 37 to which the side walls 37a, between which the riveter 44 is arranged, are fixed.
By way of the vertical movement of the riveters 41, 42, 43, 44 it is possible to move the upper face of the riveters 41, 42, 43, 44 into a position that is substantially coplanar with the upper side of the side walls 38a, 35a, 36a, 37a, as shown for example in
By way of the movement of the riveters 41, 42 parallel to the advancement direction 7 and of the riveters 43, 44 at right angles to the advancement direction 7, the bending and therefore the riveting of the nails is produced during the nailing operation performed by the nailing clamps 14.
It should be noted that the three assemblies constituted by the second pusher 23, by the third pusher 24 and by the fourth pusher 25 with the corresponding actuation elements, with the riveter 42, 43, 44 arranged between the side walls 35a, 36a, 37a and with the corresponding gearmotor for the actuation of the riveter 42, 43, 44, can be constituted by three modules that are substantially mutually identical. For the sake of simplicity,
The module that supports the riveter 41 can be provided in a manner similar to these three modules, with the difference that the chains 20, instead of being limited to the module, are extended to the composition station 2.
Preferably, in the machine according to the invention there are two pairs of rows 12a, 12b and 13a, 13b of nailing clamps 14, respectively: a first pair of rows 12a, 12b of nailing clamps 14, which are oriented parallel to the advancement direction 7, and a second pair of rows 13a, 13b of nailing clamps 14, which are oriented at right angles to the advancement direction 7.
Furthermore, there are means 46 for varying the individual position of the nailing clamps 14 parallel to the direction along which the corresponding row of nailing clamps 14 is extended.
More particularly, the nailing clamps 14 are mounted on a corresponding supporting structure 47, which is arranged at the nailing station 4 above the resting and sliding surface 18. The supporting structure 47 of the nailing clamps 14 can move vertically with respect to the resting and sliding surface 18 and is surmounted by an actuation structure 48 or hammer, to which it is coupled.
In turn, the actuation structure 48 is supported by two shoulders 49, 50 and can move on command vertically, with an actuation stroke, downwardly so as to actuate the strikers 51 of the nailing clamps 14 and upwardly so as to space the nailing clamps 14 above the resting and sliding surface 18.
More particularly, the supporting structure 47 of the nailing clamps 14 has a plan shape substantially diamond-like with cut corners, i.e., octagonal, and supports the two pairs of rows 12a, 12b, 13a, 13b of nailing clamps 14 that are arranged proximate to the diagonals of the diamond. Each row 12a, 12b, 13a, 13b of nailing clamps 14 is mounted on a corresponding threaded shaft 52a, 52b, 53a, 53b. The two threaded shafts 52a, 52b that support the two rows 12a, 12b of nailing clamps 14 oriented parallel to the advancement direction 7 are supported, so as to be able to rotate about the corresponding axes, which are parallel to the advancement direction 7, by the supporting structure 47, and are mutually connected, in rotation about the corresponding axes, by means of a pinions-and-chain connection 54, which is arranged at an axial end thereof. One of these threaded shafts, constituted in the illustrated embodiment by the threaded shaft 52a, is connected, by means of its opposite axial end, to a gearmotor 55, which can be operated in order to turn the threaded shafts 52a, 52b.
Likewise, the two threaded shafts 53a, 53b that support the two rows 13a, 13b of nailing clamps 14 oriented at right angles to the advancement direction 7 are supported, so that they can rotate about the corresponding axes, which are perpendicular to the advancement direction 7, by the supporting structure 47, and are mutually connected in rotation about the corresponding axes by means of a pinions-and-chain connection 56, which is arranged at an axial end thereof. In this case also, one of these threaded shafts, constituted in the illustrated embodiment by the threaded shaft 53a, is connected, by means of its opposite axial ends, to a gearmotor 57, which can be activated in order to turn the threaded shafts 53a, 53b.
The means 46 for varying the position of each nailing clamp 14 along the direction along which the row 12a, 12b, 13a, 13b to which it belongs is extended comprise the corresponding threaded shaft 52a, 52b, 53a, 53b, a female thread, not shown in the figures, which engages the threaded shaft 52a, 52b, 53a, 53b and is supported, so that it can rotate about the axis of the same threaded shaft 52a, 52b, 53a, 53be inside the body of the corresponding nailing clamp 14. On the body of each nailing clamp 14 there is a corresponding fluid-operated cylinder 58, which can be actuated on command in order to engage, by means of the stem of its piston, said female thread so as to lock it with respect to the body of the nailing clamp 14. Substantially, when the female thread is free to rotate about the axis of the corresponding threaded shaft 52a, 52b, 53a, 53b with respect to the body of the corresponding nailing clamp 14, the rotation of the threaded shaft 52a, 52b, 53a, 53b has no effect on the position of this nailing clamp 14, while when the female thread is locked with respect to the body of the nailing clamp 14 as a consequence of the actuation of the fluid-operated cylinder 58 the rotation of the corresponding threaded shaft 52a, 52b, 53a, 53b produces a movement, in one direction or in the opposite direction, depending on the direction of rotation of the threaded shaft 52a, 52b, 53a, 53b, along said threaded shaft 52a, 52b, 53a, 53b.
The nailing clamps 14 can be constituted by nailing clamps 14 of a known type, with a body to which a channel 59 for feeding the nails is connected and with a striker 51 that protrudes from the upper side of the body of the corresponding nailing clamp 14 and can be actuated downwardly in order to actuate in each instance the expulsion of a nail from the lower side of the corresponding nailing clamp 14.
The supporting structure 47 of the nailing clamps 14 hangs from the overlying actuation structure 48 by means of two tension members 61, 62. The connection between the supporting structure 47 of the nailing clamps 14 and the actuation structure 48 by means of the two tension members 61, 62 is provided so that, when the nailing clamps 14 rest against the upper face of the flange 3 at the nailing station 4, the actuation structure 48 can descend further with respect to the supporting structure 47 of the nailing clamps 14 so as to act on the upper end of the strikers 51 in order to push them downwardly so that they drive the nails into the flange 3 and so that when the actuation structure 48 is lifted, beyond a first extent required in order to allow the rearming of the strikers 51, it drags upwardly also the supporting structure 47 of the nailing clamps 14 so as to space it above the flange 3 arranged in the nailing station 4.
The supporting structure 47 of the nailing clamps 14 is guided, in its vertical motion, by wheels 63, which slide along guides 64 that are applied to the two shoulders 49, 50 which support also the actuation structure 48 so that it can slide along the vertical direction.
The actuation structure 48 is constituted by a substantially cross-shaped beam, in a manner similar to the arrangement of the rows 12a, 12b, 13a, 13b of nailing clamps 14, so as to engage, with its lower side, against the upper end of the strikers 51 of the nailing clamps 14 during its lowering along the shoulders 49, 50.
The vertical movement of the actuation structure 48 is actuated by means of a gearmotor 65 which is connected, by means of its output shaft, to a main actuation shaft 66 by means of a chain connection, of which only the pinions 67 have been shown. The main actuation shaft 66 is supported, so that it can rotate about its own axis, which is oriented at right angles to the advancement direction 7, by the shoulders 49, 50.
The main actuation shaft 66 is connected, with each of its axial ends, to the actuation structure 48 by means of a transmission constituted by a rod 68 and a crank 69.
The upper end of each one of the rods 68 is hinged to a block 70, which is supported by the actuation structure 48 in a manner that allows vertical sliding.
Advantageously, there are means for adjusting the height position 71 of the actuation structure 48 and therefore of the supporting structure 47 of the nailing clamps 14 as a function of the thickness of the flange 3 to be assembled. These adjustment means comprise, for each block 70, a gearmotor 72, which is connected, by means of its output shaft, to a threaded shaft 73 that mates with a female thread 74 arranged inside the block 70. The body of the gearmotor 72 is fixed to the actuation structure 48 so that the actuation of the gearmotors 72 produces the vertical movement of the actuation structure 48 with respect to the block 70.
In this manner, by means of the actuation of the gearmotors 72 it is possible to vary the height position of the actuation structure 48 independently of its actuation stroke imposed by the connection with a rod 68 and a crank 69 that exists between the main actuation shaft 66 and the actuation structure 48.
The two shoulders 49, 50 are fixed by means of their base to the main supporting structure 16 and are mutually connected, proximate to their upper end, by two crossmembers 75, 76, which are perpendicular to the advancement direction 7, thus providing a sort of portal, which is located at the nailing station 4 and through which the flange 3 is made to pass.
The rotation means 11 comprise a lower shaft 77, which has a vertical axis and is provided, at its upper end, with a lower claw 78 and with an upper shaft 79, which is arranged coaxially to the lower shaft 77 and is provided, at its lower end, with an upper claw 80. The lower shaft 77 and the upper shaft 79 are arranged with their axis at the main axis 15.
The lower shaft 77 and the upper shaft 79 can move along the corresponding axis, i.e., along the main axis 15, in order to engage, by means of the claws 78, 80, respectively the lower face and the upper face of the flange 3 that is arranged in the nailing station 4 or disengage from said flange 3.
Both the lower shaft 77 and the upper shaft 79 can rotate about the common axis, i.e., about the main axis 15, in order to turn the flange 3 about its own axis.
More particularly, the lower shaft 77 is supported, so that it can rotate freely about its own axis and so that it can slide along said axis, by a part of the main supporting structure 16.
The lower shaft 77 is connected to the stem of the piston of a fluid-operated cylinder 81, which can be actuated in order to translate the lower shaft 77 along its own axis with respect to the main supporting structure 16.
The upper shaft 79 is supported, so that it can rotate about its own axis and so that it can slide along said axis, by a corresponding supporting structure 82, which is connected, as will become better apparent hereinafter, to one of the crossmembers 75, 76 that mutually connect the two shoulders 49,50.
More particularly, the upper shaft 79 is supported by the supporting structure 82 by means of a pair of bearings 83 and is fixed, with its upper end, to the output shaft of a gearmotor 84, which is mounted on the supporting structure 82 and can be actuated in order to turn about its own axis the upper shaft 79 with respect to the supporting structure 82.
In turn, the supporting structure 82 is supported so that it can slide along vertical guides 85, which are fixed to a framework 86 that is fixed to the crossmember 75. The body of a fluid-operated cylinder 87 having a vertical axis is fixed to said framework 86 and is connected by means of the stem of its piston to the supporting structure 82 and can be actuated in order to move the supporting structure 82 along a vertical direction and therefore to translate the upper shaft 79 along its axis with respect to the crossmember 75.
The supporting structure 82 has a substantially cylindrical enclosure 82a, which protrudes downwardly and accommodates much of the upper shaft 79. The enclosure 82a, with the upper shaft 79, passes through a hole 88, which is provided conveniently at the intersection of the branches that compose the actuation structure 48, i.e., at the main axis 15.
The force generated by the fluid-operated cylinder 81 that actuates the translation of the lower shaft 77 is conveniently greater than the force generated by the fluid-operated cylinder 87 that actuates the translation of the upper shaft 79, so that the flange 3, when it is engaged, by means of the actuation of the fluid-operated cylinders 81, 87, of the lower jaw 78 and of the upper jaw 80, is raised slightly with respect to the resting and sliding surface 18, so as to facilitate its rotation about its own axis as a consequence of the rotation of the lower shaft 77 and of the upper shaft 79 about the common axis, i.e., about the main axis 15.
The machine is completed, downstream of the nailing station 4, along the advancement direction 7, by removal means constituted by a conveyor 89, for example a chain conveyor of a known type, which constitutes an extension of the resting and sliding surface 18 defined by the bars 17 and by means of which the flange 3, once nailed, is moved away from the nailing station 4.
For the sake of completeness in description, it should be noted that the machine can be provided with a control and actuation element, of the programmable electronic type, which is connected to the various gearmotors and fluid-operated cylinders described above and to other actuation and/or control elements, of a known type and not described for the sake of simplicity, which are mounted on the machine, and can be actuated, according to preset programs, so as to control and monitor the operation of the machine.
Operation of the nailing machine according to the invention is as follows.
The flange 3 to be assembled is composed at the composition station 2 by arranging on the resting and sliding surface 18 a first layer of strips 8a that are oriented at right angles to the advancement direction 7 and by superimposing on the latter a second layer of strips 8b that are oriented parallel to the advancement direction 7.
The flange 3 thus composed is transferred, by means of the first pusher 19 actuated by the chains 20, from the composition station 2 to the nailing station 4, stopping the flange 3 with its axis at the main axis 15. The correct placement of the flange 3 in the nailing station 4 is achieved by placing the second pusher 23, which by cooperating with the first pusher 19 also compacts the strips 8a of the lower layer along a direction that is parallel to the advancement direction 7.
At this point, the other compaction means 9 are actuated, i.e., the third pusher 24 and the fourth pusher 25 are actuated and engage the upper layer of strips 8b, performing their compaction along a direction that is perpendicular to the advancement direction 7.
It should be noted that the presence of the teeth 39, 40 allows to achieve effective compaction of the two layers of strips 8a, 8b, preventing hindrance of the correct compaction of the other layer if one of the two layers has larger dimensions along one of the above cited directions.
With the layers of strips 8a, 8b thus compacted, the actuation structure 48 is actuated downwardly and causes the resting of the nailing clamps 14 against the upper face of the flange 3. As a consequence of this resting, the supporting structure 47 of the nailing clamps 14 stops its descent, while the actuation structure 48 continues its downward motion, actuating the strikers 51 of the nailing clamps 14, which drive one nail for each nailing clamp 14 into the flange 3.
During the execution of nailing, the riveters 41, 42, 43, 44 are actuated so as to perform the riveting bending of the nails.
The particular arrangement of the nailing clamps 14 according to the invention achieves the results of obtaining, already at the end of this first nailing operation, the mutual connection of the various strips 8a, 8b that compose the two layers. Thanks to this fact, the flange 3 no longer needs to be kept under the action of the compaction means 9.
At the end of the first nailing operation, the actuation structure 48 is again raised, lifting, after a first extent which has no effect, the supporting structure 47 of the nailing clamps 14 and therefore disengaging the nailing clamps 14 from the upper face of the flange 3.
At this point the fluid-operated cylinders 81, 87 of the rotation means 11 are actuated so as to cause the movement of the lower shaft 77 and of the upper shaft 79 along the common axis, i.e., along the main axis 15, respectively upwardly and downwardly so as to engage them, by means of the corresponding claws 78, 80, against the lower face and against the upper face of the flange 3. It should be noted that the different force generated by the fluid-operated cylinders 81, 87, as explained earlier, produces a slight rise of the flange 3 above the resting and sliding surface 18.
At this point, after spacing the pushers 19, 23, 24, 25 from the sides of the flange 3 and optionally moving the pushers 23, 24, 25 below the resting and sliding surface 18 so that they do not hinder the rotation of the flange 3 about its own axis, the gearmotor 84 is actuated and causes the rotation of the upper shaft 79 about its own axis, i.e., about the main axis 15 and consequently the rotation of the flange 3 about its own axis through an angle of preset breadth.
The flange 3, by acting on the fluid-operated cylinders 81, 87, is again lowered and rested on the resting and sliding surface 18.
The actuation structure 48 is then lowered again, in a manner similar to what has already been described in the preceding nailing step, performing a new nailing, which is angularly offset, about the main axis 15, with respect to the nailing performed previously.
One then proceeds as already described above, providing a plurality of nailing steps until the assembly of the flange 3 is completed.
It should be noted that the particular arrangement, according to the invention, of the nailing clamps 14 allows to complete the nailing of the flange 3 by rotating it about the main axis 15 through an angle of 90°, instead of through an angle of 180°, as instead occurs in nailing machines of the traditional type. Thanks to this fact, the time required to complete the assembly of the flange 3 is reduced.
Once the nailing operation has been completed, the nailing clamps 14 are disengaged upward from the flange 3, which, by means of the actuation of the first pusher 19 and by means of the actuation of the conveyor 89, after moving the second pusher 23 below the resting and sliding surface 18, is moved away from the nailing station 4 in order to make room for a new flange 3 to be assembled.
In practice it has been found that the nailing machine according to the invention achieves fully the intended aim, since thanks to the particular arrangement of the nailing clamps it allows to reduce the time required to assemble the flanges of wooden spools for winding electrical cables, steel cables, ropes, fiber optic cables or wire-like elements in general, with respect to nailing machines of the traditional type.
Furthermore, thanks to the fact that already at the end of the first nailing step, i.e., with a single nailing "beat", the strips of the two layers are mutually assembled, the machine according to the invention abolishes the need to perform rotation, together with the flange, of the compaction means, as instead occurs in nailing machines of the traditional type. This fact achieves the goal of simplifying the entire structure of the machine, allowing a reduction of overall production costs.
A further advantage of the nailing machine according to the invention is that it is possible to vary, in a completely automated manner, the position of the nailing clamps as well as the height position of the actuation structure of the nailing clamps independently of its stroke. Thanks to this fact it is possible to adapt the nailing machine to various flange formats extremely rapidly and without requiring manual interventions on the machine.
The nailing machine thus conceived is susceptible of numerous modifications and variations within the scope of the appended claims. In practice, the materials used, as well as the dimensions, may be any according to requirements and to the state of the art.
Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.
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