HK1025280B - Method and machine for sawing panels with laterally movable pusher - Google Patents

Description

Method for sawing boards and board sawing machine with a laterally displaceable pusher

Technical Field

The invention relates to a board sawing machine. In particular, but not exclusively, for cutting boards, blanks or sheets mainly made of wood-based materials, but also for cutting plastics, light metal alloys, steel, composite boards and inorganic plywood to form smaller panels.

The invention is particularly applicable to machines for sawing wood-based materials, comprising a horizontal table on which there is a moving device known as a pusher which can push at least one board downstream towards a sawing (or rotating) device, where the board is positioned by suitable fixing means gripping its rear edge during sawing, and any auxiliary positioning, alignment, transport, pressure and rotating parts which constitute standard equipment for such machines.

Background

Known machines of this type are generally provided with a plurality of fixed elements, for example of the gripper type, mounted side by side in a given direction perpendicular to the forward (or reverse) feed direction of the sheet and acting on the trailing edge of the sheet to be cut.

These known machines are used for sheets of various dimensions (width and length), which are generally placed one on top of the other in a large stack, the size of which depends on the dimensions of the sheet formed by the platemaking machine.

Conventional board sawing machines can be simple, with a single cutting axis, called the longitudinal axis, located downstream of the pusher; or a complex machine with 2 (or more) cutting axes at an angle to each other and a feed table with plates positioned at an angle of 90 to each other. In more complex machines, these cutting axes are located downstream of the respective pushers, the first being called longitudinal axis and the second being called transverse axis.

In these known machines, the same pusher can saw two or more stacks of plates (or small plates) in sequence. Furthermore, if the cutting axes of the machine correspond to the cutting lines of a stack of plates of different sizes, the stack of plates of different sizes placed side by side can only be sawn simultaneously (forming a so-called logical cutting pattern). If the cutting is not constant, (different cutting patterns are formed), several pushers may be provided, each pusher acting on 1 (or several) small plates, or on a part of the plate, with the result that the structure becomes complex and the cost of the whole machine increases.

Depending on the size of the stack or group of small plates to be sawn (whether of the original size or pre-cut size), the machine must be equipped with a suitable number of fixing elements suitably positioned and distributed along the whole rear edge of this relative stack or group of plates, in order to firmly fix the plates along the whole width and to reliably line them up against the stop surface during the sawing operation.

One of the disadvantages of the known board sawing machines is that they are constructed and equipped only for cutting a limited number of board stacks or groups of board stacks of a limited size. Here, a variable number of fixing elements or grippers are mounted on the pusher stack according to the end user requirements. In other words, in order to reduce costs, the manufacturer, who has mounted the pusher's beam in a fixed position with a plurality of holders or grippers variably distributed along the length of the beam, uses the fewest possible components.

These machines are therefore not flexible in terms of changing dimensions and are therefore not suitable for cutting plates of different dimensions unless complex components are provided, but this significantly increases the manufacturing costs and requires expensive tooling; let alone the fact that: although this machine is a long term investment, its capacity does not meet the process requirements after many years of work, not only because the market needs are diverse and constantly changing.

Description

The basic object of the present invention is to overcome the drawbacks of the prior art by means of a board sawing machine having 1 or 2 (or more) cutting axes that can be adjusted in an extremely simple and practically feasible manner to work a board, or a small board group, of any size.

One of the advantages of the invention is that: even if it is necessary to cut adjacent plates and/or platelets one after the other into smaller plates of different length and width, it is possible to cut one or more plates and/or platelet stacks placed side by side, either longitudinally or transversely (depending on the machine used).

Another advantage is that it provides a machine that can produce panels of various sizes, both long and wide, with a considerable reduction in the number of cutting operations and in a considerable saving of time.

To achieve the above objects and advantages, the present invention provides a board cutting machine comprising: a horizontal table supporting at least one plate to be cut; at least one movable device for pushing the plate along the table in the direction of feed or in the opposite direction, in such a way that the plate is fed to a sawing device for cutting the plate into 2 or more smaller plates in a direction perpendicular to the direction of feed and/or to a rotating device, the movable device being provided with two or more holding elements for holding in place the rear edge of the plate when sawn, the holding elements being mounted side by side on the movable device in such a way that: the driving device can push the conveying device along the horizontal direction vertical to the conveying direction, and is characterized in that: the drive means is arranged to urge at least one of the securing members automatically and independently of the other securing members.

The invention also provides a method of sawing boards with a board sawing machine comprising a horizontal table for supporting at least one board to be sawn; -a movable device for pushing the board along the table in a conveying direction to be fed to a device for sawing the board into 2 or more smaller boards in a direction perpendicular to the conveying direction, the movable device being provided with at least 2 rear edges for fixing the boards each in place when sawing the boards, the method being characterized in that:

-attaching the fixture for carrying out the method to a mobile device in such a way that: if necessary, all but one of them can be moved in the horizontal direction perpendicular to the conveying direction by the driving device;

at least one of the fixed parts is mounted in such a way that the drive means can move it in the conveying direction in 2 directions with respect to the movable means itself;

the plates are picked up by the holders and then the holders are moved in the transport direction, in 2 directions with respect to the mobile device itself, in such a way as to position the plates so that their cutting lines are aligned before being sent to the sawing device.

Other features and advantages of the present invention will become apparent from the following detailed description, which proceeds with reference to the accompanying drawings, which illustrate preferred embodiments of the invention and in which:

FIG. 1 is a schematic top view of the machine of the present invention having a single longitudinal cutting axis;

FIG. 2 is an enlarged view of the right-hand side detail of FIG. 1;

FIGS. 3a-3f are schematic top views of possible cutting configurations of the present invention using two holders;

4a-4d1 are schematic top views of possible machining configurations of the machine of FIG. 1, which differ according to the size of the board to be cut and the characteristics of the machine itself;

figures 5a-5u are schematic top views of possible working configurations of the machine with two (angled) cutting axes, which differ according to the dimensions of the sheet to be cut and the characteristics of the machine itself;

fig. 6a-6f are schematic top views of different stages in a cutting operation that may be performed by the machine of the present disclosure.

Referring now to fig. 1, numeral 1 designates a board sawing machine with a single longitudinal cutting axis, typically for cutting large-size whole boards (as shown) or boards 3a and 3b placed side by side. In this description reference is made to cutting a board of wood or a wood-based material, without thereby limiting the scope of the invention.

The machine 1 is intended to cut the sheets 30 and 3a, 3b into smaller sheets 31 or 4a, 4b of the same or different widths.

The machine 1 comprises a horizontal table 5 supporting at least one plate to be cut. The table is constructed in such a way that: which facilitates the sliding of the board or board stack thereon in the input direction indicated by arrow F, or in the reverse direction indicated by arrow F1, in the event that the board or board stack is input from the front/operator side OP of the machine (as will be described in more detail below). In this particular case, the table 5 with the stack or stacks of plates is carried by a conveying and carrying device (not shown). By way of example, figure 1 shows two stacks of plates 2a and 2b placed side by side, which may alternatively constitute a single plate stack 2 (see figure 2) having dimensions not greater than the sum of the plates 2a and 2 b.

The pallet may, for example, comprise a plurality of unloaded rollers rotating about axes perpendicular and/or parallel to the input direction, or, according to another embodiment (as shown in fig. 2), the pallet may comprise a plurality of brush-like supports 20 (either low friction fibres or air cushions) with a top forming a horizontal surface on which the board can slide. The station can also be provided with rotating means schematically illustrated and identified with the reference R, which turn the plate by 90 ° when necessary, as will be explained in more detail below with reference to the illustrations showing the different process stages. According to this simplest embodiment, the rotating means may consist of gripping means which grip the corners of the panel and move the panel in the direction F, F1 to turn the panel.

The machine is provided with means for moving the board along the table 5 according to the input direction F or F1, said means comprising movable means 6 which can push the board 3 or 3a, 3b along the table 5 according to the direction F towards longitudinal sawing means 7 (or pull the board in the direction F1), means 7 for dividing the board into smaller boards. The pusher 6 is mainly constituted by a beam that can move in this way in the direction of transport in various stages of preset length; it conveys the plate pack 2 or 2a, 2b to a sawing device 7. During the stop between one step and the next, the sawing device 7 cuts the plate pack at an angle perpendicular to the transport direction.

Reference numeral 50 denotes an air cushion table on the operator's side, which is used to support and receive the board of the input or output sawing device 7. The letters SX and DX refer to the zero reference lines on the left and right hand sides of the machine, respectively.

The plate 4 or 4a, 4b output from the sawing device 7 is then transported to another processing station not shown in the figure.

The pusher 6 has at least one fixing element 16 for fixing the plate in a certain position during the sawing operation. Each fastener 16 acts on a portion of the rear edge of the board and prevents the rear edge from moving as the board is sawn.

The device 6 is preferably provided with a plurality of fixed elements (as shown in figure 1) placed side by side in a horizontal direction perpendicular to the transport direction of the panels. Each fixing element, for example, may comprise a clamp formed by first and second clamping members 17 and 18, the first clamping member 17 being adapted to press down on the edge of the panel at the top of the stack, the second clamping member 18 acting on the lower edge of the panel: in this case, the gripping members 17 and 18 cooperate to form 2 jaws which hold the entire plate stack at its rear edge.

The gripping members 17 and 18 are driven by conventional drive means, such as hydraulic drive 16a, shown schematically in figure 2.

Fig. 1 shows a plurality of fixing members 16 irregularly spaced in a direction perpendicular to F. In the situation shown in the figure, the distribution of the pieces is more concentrated on the left-hand side, which is the reference side SX of the sawn pack, although as described below, the right-hand reference side DX may also be used. To facilitate the construction of the assembly, it is preferred that all of the fastening elements are identical.

According to the invention, at least one fixing element 16 (or better all the elements except the first one referenced 160 from the left) must be mounted on the pusher 6 in such a way that: it can be moved back and forth in a horizontal direction perpendicular to the conveying direction, as indicated by an arrow H in fig. 1.

This is achieved by a sliding engagement of the fixing 16 with a straight horizontal guide rail 15, which is shown schematically in fig. 2 and is integral with the pusher 6.

A device shown schematically at 36 in figure 1 is also used to control the left and right lateral movement of the various mounts. These control means may, for example, be constituted by a threaded guide 36a, the guide 36a being integral with the cross member 6, engaging with an electric device designated 36b, guided in a screw-operated manner and integral with each fixing 16. These control means are equipped with a computer in order to position the fixing in the most suitable position along the rear edge of the panel to ensure safe and reliable fixing on the panel, regardless of the lateral position of the panel with respect to the table and of how wide the latter is.

In this respect, fig. 3a-3f schematically illustrate 6 different positions that can be adopted by the two-piece fixing, depending on the number and size of the plates 3 to be sawn. In fact, by having a small number of fixing elements 16 (in this case only 2) suitably positioned in the transverse direction, a plate 3 of any size can be fixed in position while it is being sawn.

Thanks to this controlled positioning solution, it is possible to saw 2 or more plates placed side by side, or several groups of plates of different sizes fed one after the other, with the same sawing device, while fixing them with a small number of fixing elements 16.

With such a controlled positioning solution, more than two side-by-side boards to be sawn can be firmly fixed with only a few fixing means 16, which can be done simultaneously by feeding boards of different sizes in sequence with the same sawing machine. This allows a machine to be made universal, to be used with panels of different sizes, by a simple and time-saving setting operation of the operator (or of a control system able to identify the dimensions of the panels), which takes up negligible time.

Figures 3a-3f simply illustrate how different size panels can be controlled with only two fasteners (the minimum number of pieces required).

Figures 3a-3e show some possible operating configurations of the grippers on the pusher 6, these figures being differentiated according to the width of the plate to be cut: note that the gripper is located at the most appropriate width of the plate or plate stack.

In the case of a single plate as shown in fig. 3a, one gripper 16a is sufficient, whereas in the case of a plate 3 side by side as shown in fig. 3b, a gripper 16b has to be used. Similarly, in the example shown in FIG. 3c, each gripper 16a, 16b is designed to hold half of 2 (or more) thinner boards, and the size and carrying capacity of the gripper is such that more than one board can be pulled in direction F1 or pushed in direction F (FIG. 3c shows 2)

Figures 3d-3f additionally show the various grippers which are positioned differently on the pusher according to the different sizes of the single large-size plate 3. It is again noted that the gripper can be positioned in the longitudinal direction (fig. 3e, 3f and in the transverse direction along fig. 3d) where it is most suitable for the size of the board or board stack, in order to pre-cut it.

A further feature of the invention is that at least one of the securing members 16, designated 161 in fig. 2, is not only movable in the transverse direction (direction H) relative to the pusher 6, but also in the longitudinal direction towards or opposite the feed direction (K). The mount 161 is preferably located below the beam 6 for structural reasons (to be described in more detail below) to enable it to be moved to different positions. It is moved along H by means of a second guide 15a and along K by means of a similar third guide 15b, each having respective drive means 38a and 38b of known type.

There may be 1 or more fixed members 161 that are controllably movable in the direction K, in which case each fixed member 161 must be provided with drive means that enable it to move independently of the other members 161.

Fig. 2 shows 1 or several pieces 16, in this case indicated 161, which pieces 16 can also be moved in the vertical direction 2 along the 4 th guide rail under the drive of the drive means 39: this means that the relevant gripper can be lifted from the table, so that the pusher beam can be returned to the ready, retracted position by still moving over the processed plate or plate stack without coming into contact therewith. This feature will be described in more detail below.

The forward and retraction movements of the holder 16 along the 3 axes H, K, Z, as well as their lateral and vertical movements, are controlled by conventional computer-equipped controller means (not shown) driving all the axes of the machine.

The different working configurations that can be obtained with the machine described above will now be described with the aid of the schematic drawing of fig. 4.

In fig. 4a-4f, the process cycle of the board sawing machine is assumed to be a single longitudinal cutting axis carrying the board (or board stack, from now on, for convenience, referred to as board) from the front, i.e. from the operator side OP. The clamps (see figure 4a) are moved into regularly spaced positions along the length of the board at H, see right hand side neutral DX: once the gripper 16 grips the plate, the pusher moves back in direction F1. In fig. 4b, the pusher beam pushes the sheet material in direction F to make a first trim cut T1, a second longitudinal cut T2 (at least one) and a final cut T3 (see fig. 4 c). In fig. 4d, after the operator OP has turned the platelet from which the plate was cut, the pusher has moved back in the direction F1 and the gripper has moved to a new position to hold the platelet (in this case 2 plates), now with reference to the left-hand line SX. The pusher (see fig. 4e) pushes the small plate in the direction F to the first trim cut T4, and then, in fig. 4F, continues to move forward in the direction F, so that at least one cross cut T5 can be formed: in this case, however, the gripper (only one gripper designated 161 in the figure) must also be moved in the direction K in order to assume a different position relative to the pusher beam 6 which continues to move in the direction F.

The process cycle of fig. 4g-4R again relates to a board sawing machine provided with a single longitudinal cutting axis and carrying boards from the front, i.e. from the operator side, but in this case the machine also has a separate turning device R. Moving the clamp (see figure 4g) by H along the length of the plate into a position in which it is regularly spaced, with reference to the right hand neutral DX; once the gripper grasps the plate, the pusher moves back in direction F1. In fig. 4h, the pusher is according to pre-cut. The plate is positioned by rotating the PT, the gripper is opened, the pusher is moved back a little and the gripper is raised. The rotating device R (in practice connected to the gripper) now comes into operation, which in the example shown is a rectilinear device, which moves along the axis F1 and which, in conjunction with the reference piece B1 of the carrier tape (in practice the counter-roller), turns the plate by 90 °. During the joint movement of the rotating device R and the reference piece B1, the pusher and the gripper move into a new position enabling them to grip the short side of the plate. The pusher is advanced (see fig. 4j), the gripper grasps the short side of the plate, the pusher then positions the plate, first for trimming, then precut (or precut several times, see fig. 4k), after which the gripper 162 is raised (see fig. 41), while the outer right-hand gripper 16 and the pusher are moved to the left-hand zero position SX, so as to be able to grasp the precut plate and pull it in the direction F1. At the same time, the rotating device R, moving in the direction F and carrying the reference piece B1, can rotate the plate freely again. For this period, a pusher with a gripper 16 at the left-hand zero line SX (see fig. 4m) pushes the pre-cut platelet back in the direction F1, past the cutting line, and then (see fig. 4n) again forward in the direction F towards the transverse cut to be made in this case. When the full transverse cut is completed, the gripper 16 used so far, which is raised to the new position (see fig. 40), is also moved along H to a position where it can grip the previously rotated main part of the plate. When the full unit 16 is in the correct position, the pusher is advanced in the direction F to make the longitudinal cut required here (see fig. 4p) with reference to the right-hand neutral line DX, and finally the various platelets reach the air cushion table, after which the gripper and pusher are moved to the gripping position again with reference to the opposite, left-hand side SX. Note that in fig. 4q, the gripper has been traversed to such a position along H; where they grasp the platelet and push back through the cutting line. Finally, as shown in fig. 4r, the pusher is advanced while the dedicated gripper 161 is advanced or returned along the axis k to make a transverse cut along a cutting line at a different distance from the end of the plate.

The process cycle shown in fig. 4s-4d1 again involves a board sawing machine with a single, longitudinal cutting axis, but in this case the machine is provided with a carrier (or carrier platform) designated cA on the opposite side of the air cushion table 50. In fig. 4s, the whole plate is placed upstream of the plate saw and then transported in direction F (see fig. 4t) and aligned longitudinally and transversely with the rotating device R (optional) and the reference R1 according to ipt. Then (see fig. 4u) the gripper is raised in direction z, while the pusher is in position in direction F1, in order to wait for the plate that has been rotated. Referring to the right hand neutral DX the grippers catch the board after it has rotated (see figure 4v) and the pusher is moved forward in the direction (see figure 4w) to make one or more cuts, after which the board is rotated on an air cushion. The grippers not used at this stage are the grippers referenced 162, rising in the direction z (see figure 4x) and one referenced 16, which move the gripper for the subsequent cutting of the small plate along H with reference to the left hand neutral line SX. In figure Y the board is turned again, while the pusher is moved back in the direction F1 with reference to the left hand zero line SX, in order to pass the pre-cut board through the cutting line. The pusher is then advanced again during the step of seating the small plate (see figure 4z) so that the plate can be cross-cut at T10. In fig. 4a1, the pusher and gripper are moved with reference to the right hand neutral wire DX (in directions F and H respectively) to grasp the main part of the board and then make a longitudinal cut T11. Next (see figure 4b1), the operator turns the board cut in this way on the air cushion table by 90 °, while the pusher and gripper move back with respect to the left hand reference neutral line SX in order to grasp these small boards. Finally (see fig. 4c1 and 4d1), the pusher is moved back to carry the small plate through the cutting line and then moved forward again in direction F to make a cross cut before the gripper 161 is not moved along K, so as to simultaneously cut 2 (or more) plates into different lengths with respect to the pusher 6.

Fig. 5a-5u illustrate a machine for sawing boards at an angle, i.e. with 2 mutually perpendicular cutting axes, designated 7 and 7a, the former being referred to as the longitudinal axis and the latter as the transverse axis. The machine has a longitudinal cutting section with a pusher 6 with a gripper 16, a carrier CA, a zero reference line SX (on the left since the input direction of the plate forms an angle coinciding with the machine angle), and a cutting input direction F. The cross section has a pusher 6a with grippers 16t and 161t, a zero reference line SXt and a cut feed direction F2 (see fig. 5 a).

After transport in direction F (see fig. 5B), the first plate or plate pack is pushed by the pusher 6 towards the rotating device R or the (optional) O PT position of the reference nest B1, while the 2 nd plate is prepared on the carrier CA. When the pusher 6 is moved back, the plate is rotated (see fig. 5c), while the gripper 162 is lifted in the direction z, so as not to affect the rotation of the plate. Then (see fig. 5d) the grippers 16 and 162 are moved into a position corresponding to the length of the short side of the plate 3. The grippers 16 and 162 must be able to move in the directions H and Z. In the next step (see fig. 5e), the pusher 6 is moved in the direction F so as to be able to cut the plate along the axis 7 into small plates S1. The small plate S1 is then immediately gripped by the grippers 16t and 161t of the transverse segment, which are moved in the direction F2 towards the 2 nd cutting line 7 a: in this configuration, the gripper 16t is preferably, but not necessarily, movable in the directions H and Z, while the other grippers, designated 161t, all or some of them are movable not only in the direction H, but also in the direction K (H and K being respectively in the direction of the pusher beam and perpendicular thereto) according to the cutting and operating requirements of the entire machine. In fig. 5f, after the beam 6a has moved the panel S1 into position and the gripper 161t has moved in relation thereto in the direction K so that the panel can be cut to different lengths as required, the remainder of the panel 3 is again rotated by the retracted beam and the associated gripper 16 is raised in the direction z. Fig. 5g shows the plate S1 after it has been put in place by the beam 6a, while the pusher 6 advances the plate 3 again in the direction F for further cutting into plates S2 (see fig. 5 h). In this case, 4 plates S2 are shown, so (as can be better appreciated from fig. 5 i) one gripper 16t and 2 grippers 161t are used. The latter are grippers for positioning the plates cut into different lengths (note also: one gripper 161t simultaneously seizes 2 plates), not yet used, when the gripper, referenced 160t, is positioned at the end of the beam 6a that is outside the cutting travel range of the shaft 7a, see also fig. 5h, which shows the unloaded beam 6a when returning in the direction F3. The grippers 16t, which "cover" the area occupied by the sheet S2 vertically, are lifted in the direction Z so as not to interfere with the sheet below, while the remaining grippers 160t (which are empty) are in position on one side. The number of grippers 160t (and 16t) used and the length of the beam 6a were calculated from the working width L5 and the overtravel width L6. Similarly, the beam 6 is moved into position to catch the next panel 3a or panel stack, indicated by lighter shades of grey. As mentioned above, fig. 5i shows 4 boards S2 gripped by grippers, which move along H and are gripped by two grippers 161t, which move along H and K, at least one of which can hold 2 or more boards simultaneously, and fig. 5i also shows 3 on one side of the cross beam 6a in an unloaded state. Fig. 5i also shows: the panel 3a is slit at 7 so that subsequent panels can be cut in a completely different pattern. The panel 3 can be subdivided into panels S3 having a width different from that of the panel S2. In fig. 5j, beam 6a is again returned unloaded in direction F3, carrying gripper 16t raised above plate S3 and gripper 160t at beam side 6a in an unloaded position. At the same time the next plate has been touched by the beam 6. In fig. 5K, the cutting axis 7a has been machined for the plate S3, while 2 grippers 16t hold the first plate (the larger one) and only one gripper 161t holds the other two plates (the thinner). At the same time, the plate 3b is sawn longitudinally at 7.

Fig. 5l-5u show a machine with 2 cutting axes, which operates in the same way as the machine just described, but with a longitudinal section of beam 6 having at least one gripper 161 movable along H and K so as to be able to control the different plates 3H, 3K placed side by side. In fig. 5m, 2 grippers 16 and 161 are pushing the sheet 3h in direction F towards the cutting axis 7 which can divide the sheet 3h into a plurality of sheets S4, which are then sent towards the beam 6 a. The now free beam 6a holds the other plate 3 k. In fig. 50, panel 3k is slit into panel S5 while panel S4 is cut at an angle perpendicular to rearmost axis 7 a. At the same time, other boards 3m, 3n have been fed into the machine. In fig. 5P, panel 3m has rotated 90 ° on the table of the longitudinal section of the machine as panel S5 is being transected. In fig. 5q, the panel S5 is cut transversely to different lengths, the panel 3m is cut into the panel S6 and the panel 3n is clamped by the beam 6. The other plates 3P (which have been cut into 2 small plates) and 3q are fed from the carrier. Next, as shown in fig. 5r, when the sheet S6 reaches the final transverse cut line, the sheet 3n is slit into sheets S7, and the beam 6 sends the double sheet 3P to the longitudinal cut line 7. As shown in fig. 5S, panel S7 is cross cut into panels of different lengths, while panel 3P is slit at 7 into panels of different widths. Finally, fig. 5u shows the later plate, which is output from the machine after cutting, while plate 3q is fed to cutting line 7.

Thus, due to the controlled movement of one or several of the fixed elements, the machine can cut sheets, even sheets placed edge to edge, into different lengths in a single operation. This concept is further illustrated by figures 6a-6f, which illustrate 6 steps in the operating cycle of a board sawing machine provided with at least one fixing 16a closest to the reference line RF (which is now on the right side) which can be moved forwards or backwards in the direction K.

Referring to fig. 6a-6f, reference numeral 6 denotes a movable pusher, 7a sawing device, 7-7 a cutting axis, 3a and 3b 2 plates of different width and equal total length (because they are produced from the same raw plate) but which are cut transversely along different lines to produce final parts of different dimensions, designated 40 and 41. These figures clearly show that: the small plates 40 and 41 differ in length: the small plate 41 at the right-hand side plate is shorter than the small plate 40 at the left-hand side. The larger or smaller number of portions 40 or 41 may be reversed relative to the reference line RF. Fig. 6 shows in particular such lines: along which the thread sheets 3a and 3b are not cut to coincide.

The first step in the saw cycle (fig. 6a) is to drive the pusher 6 in such a way that: it moves the plate into position for trim cutting. Trimming is not always required.

For the second cut to the plate (see fig. 6b), the pusher 6 is advanced, while the plate on the right is moved back with respect to it by the relative fixing elements, so that the cutting lines of the two plates coincide.

To perform the third cut (fig. 6c), the right side plate is moved backward, and to perform the fourth cut (fig. 6d), the right side plate is moved backward.

The fifth cutting operation (fig. 6e) is only performed on the right-hand side plate 3b, and for this operation the right-hand plate must be advanced while keeping the pusher 6 stationary, so that the left-hand side plate 3a is in the same position.

The sixth and final cut is made in the same way as the first step (fig. 6 f).

Thus, this indicates that: by suitably combining and carrying out the longitudinal, transverse and vertical movements of the pusher and of the holder, it is possible to simultaneously supply 2 or more boards to be sawn placed side by side, which are cut into small boards of various sizes (length and width) with a relatively small number of cutting operations, thus saving a lot of time.

The object of the present invention is achieved due to the fact that: the pusher beam is not a simple passive work tool but forms a part of an automatic system, the main part of which, i.e. the fixture, automatically adjusts the size and type of the clamped plate or small plate. Indeed, each of the fixing elements can be considered as self-gripping devices, which can move along a line parallel to the axis of the beam, along a line perpendicular to the axis of the beam and along a perpendicular line, these three movements not necessarily being applied simultaneously to all the fixing elements, each or several of the elements being independent of each other according to the requirements related to the configuration of the machine.

Another distinct advantage of the present invention is the use of a rotating device that is simple in construction and works in the following manner:

-the pusher pushes the plate (or plate stack) towards a predetermined position;

-gripper opening;

-the pusher is slightly moved back;

the rotary member R grabs the corner of the plate and then, thanks to the action of its connection means, rotates the plate by the combined action of the reference member B1 moving along a line perpendicular to the direction F1 and the linear movement of the rotary member along the direction F1;

during this operation, the pusher is moved towards a predetermined position, which is determined by the dimensions of the plate.

If the plate is to be rotated again after pre-cutting, this is done as follows:

the pusher is moved back in the direction F1 while gripping the plate in such a way that the rest of the plate is moved towards the predetermined position.

-gripper opening.

The pusher is moved back slightly.

The rotating member R grabs the corner of the plate and then, thanks to its coupling provided as a pivot, the member to be referenced B1 turns it by pushing it with a line directed towards and opposite to the conveying direction F, F1.

A rotary member moves in direction F in synchronism with reference member B1 to complete a 90 ° turn.

The foregoing invention may be susceptible to considerable modification in details of construction and application, without thereby departing from the scope of the inventive principles as hereinafter claimed.

Claims (15)

1. A board sawing machine comprising: a horizontal table (5) supporting at least one plate (30; 3a, 3b) to be cut; at least one movable device (6, 6a) for pushing the plate along the table in an input direction (F, F2) or in a direction opposite thereto (F1; F3) in such a way as to feed the plate to a sawing device (7; 7a) and/or a rotating device (R), said sawing device (7, 7a) cutting the plate (30; 3a, 3b) into 2 or more smaller plates (31; 4a, 4b) in a direction perpendicular to the transport direction (F, F2), the movable device (6, 6a) being provided with two or more holders (16) which grip in place the rear edge of the plate when sawn, the holders being mounted side by side on the movable device (6; 6a) in such a way that: -the driving means (36) can push it along a horizontal direction (H) perpendicular to the conveying direction (F, F2), characterized in that: the drive means (36) is arranged to automatically urge at least one of the fasteners (16) independently of the other fasteners (16).

2. The board sawing machine as claimed in claim 1, wherein: the fixed element (16) slides along a guide (15) integral with the movable means (6, 6a) and perpendicular to the conveying direction (F, F2).

3. The board sawing machine as claimed in claim 1, wherein: at least one fixing element, indicated with (161), is mounted on the mobile device (6, 6a) in such a way that: the drive means (38) can move it in the conveying direction (F, F2) in two directions (K) with respect to the mobile means themselves.

4. The board sawing machine as claimed in claim 1, wherein: the mobile device (6, 6a) is provided with 2 or more of said fixed elements (16, 161) mounted side by side along a horizontal direction (H) perpendicular to the conveying direction (F, F2), at least one of which is mounted on the mobile device (6, 6a) in such a way that it is movable in the horizontal direction (H); the drive means (38) can move it in a conveying direction (F, F2), in two directions (K) with respect to the mobile means themselves.

5. The board sawing machine as claimed in claim 1, wherein: the mobile device (6, 6a) is provided with 2 or more fixed elements (16, 161, 162) mounted side by side along a horizontal direction (H) perpendicular to the conveying direction (F, F2), at least one of which (16) is mounted on the mobile device (6, 6a) in such a way that it can move along the direction (H) perpendicular to the conveying direction (F, F2); at least one movable device (6, 6a) mounted so that it can be moved by a drive device (38) along a transport direction (F, F2) in relation to two directions (K) of the movable device itself; and at least one piece (162) is mounted on the movable means (6, 6a) in such a way that the drive means (39) can move it up and down in the vertical direction (z).

6. The board sawing machine as claimed in claim 1, wherein: the movable device (6) forms part of a board sawing machine with a single longitudinal cutting axis (7), the device (6) being provided with 2 or more fastening members (16, 161) arranged side by side in a horizontal direction (H) perpendicular to the transport direction (F), at least one of which is mounted on the movable device (6) in such a way that it can be moved in the direction (H).

7. The board sawing machine as claimed in claim 6, wherein: at least one fixed element, designated by the reference numeral (161), is movable by means of a drive device (38) along a transport direction (F) in two directions (K) with respect to the mobile device itself.

8. Trigger sawing machine as claimed in claim 6, characterised in that the movable means (6) are provided with 2 or more of said fixed elements (16, 161) placed side by side in a horizontal direction (H) perpendicular to the transport direction (F), wherein at least one element (16) is mounted on the movable means (6) in such a way that it can be moved in a direction (H) perpendicular to the transport direction (F), and at least one element (161) is mounted on the movable means (6) in such a way that it can be moved in the transport direction (F) by the drive means (38) in a direction (K) relative to the movable means itself.

9. The board sawing machine as claimed in claim 6, wherein: the mobile device (6) is provided with 2 or more of said fixed elements (16, 161, 162) mounted side by side in a horizontal direction (H) perpendicular to the conveying direction (F), at least one element (16) being mounted on the mobile device (6) in such a way as to be movable in the direction (H) perpendicular to the conveying direction (F), at least one element (161) being mounted on the mobile device (6) in such a way as to be movable by means of a drive means (38) in two directions (K) relative to the mobile device itself in the conveying direction (F), at least one element (161) being mounted on the mobile device (6) in such a way as to be movable up and down in the vertical direction (z) by means of a drive means (39).

10. The board sawing machine as claimed in claim 1, wherein: the mobile device (6) forms part of a board-sawing machine with 2 cutting axes, a longitudinal cutting axis (7) and a transverse cutting axis (7a) associated with the mobile devices (6) and (6a), respectively, each of which is provided with 2 or several of said fixed elements (16, 161) mounted side by side in a horizontal direction (H) perpendicular to the conveying directions (F) and (F2), respectively, at least one of the fixed elements of each mobile device being mounted on the respective mobile device (6, 6a) in such a way as to be movable in the direction (H).

11. The board sawing machine as claimed in claim 10, wherein: at least one fixed element, designated by the reference numeral (161), of each mobile device (6, 6a) is mounted on the respective mobile device in such a way that the drive means (38) can move it in a conveying direction (F, F2), in two directions (K) with respect to the mobile device itself.

12. Trigger sawing machine as claimed in claim 10, characterized in that each movable means (6, 6a) is provided with 2 or more securing members (16, 161) arranged in a horizontal direction (H) perpendicular to the conveying direction (F, F2), wherein at least one member (16) is mounted on the movable means (6, 6a) in a movable manner in a direction (H) perpendicular to the conveying direction (F, F2), and at least one member is mounted on the movable means (6, 6a) in a manner that the drive means (38) can move it in the feed direction (F) in 2 directions (K) relative to the movable means themselves.

13. The board sawing machine as claimed in claim 10, wherein: each movable device (6, 6a) is provided with 2 or more of said fixed elements (16, 161, 162) mounted side by side along a horizontal direction (H) perpendicular to the conveying direction (F, F2), at least one of which (16) is mounted on the movable device (6, 6a) in such a way that it can move along the horizontal direction (H) perpendicular to the feeding direction (F, F2); at least one piece (161) mounted on the mobile device (6, 6a) in such a way that the drive means (38) can move it in the conveying direction, in both directions (K) with respect to the mobile device itself; at least one piece (162) is mounted on the movable means (6, 6a) in such a way that the driving means (39) can move it up and down in a vertical direction (z).

14. A method for sawing boards with a board sawing machine comprising a horizontal table (5) for supporting at least one board (3a, 3b … … 3n) to be sawn; -movable means (6, 6a) for sawing the board into 2 or more smaller boards (40, 41 … … n) in a direction perpendicular to the conveying direction (F, F2), the movable means being provided with at least 2 trailing edges for fixing the board in place for each board when sawing the board, the method being characterized in that:

-attaching the fixed element (16a, 16b … 16n) for carrying out the method to the mobile device (6, 6a) in such a way that: if desired, all but one of them can be moved in a horizontal direction perpendicular to the conveying direction (F, F2) by means of a drive device (36);

-at least one of the fixed elements (16b … … 16n-1) is mounted in such a way that the drive means (38) can move it in a transport direction (F, F2), in 2 directions (K) with respect to the mobile means themselves;

-each plate (3a, 3b … … 3n) is picked up by a holder (16b … … 16n-1) and then the holder (16b … … 16n-1) is moved in the transport direction (F, F2) in 2 directions (K) with respect to the mobile device itself, in such a way as to bring the plate (3a, 3b … … 3n) into position so as to align its cutting line before being sent to the sawing device (7, 7 a).

15. The method of claim 14, wherein:

-attaching the fixed element (16a, 16b … … 16n) for carrying out the method to the mobile device (6, 6a) in such a way; if desired, all but 1 of them can be moved by the drive means (36) in a horizontal direction (H) perpendicular to the conveying direction (F, F2);

-at least one of the fixed elements (16b … … 16n-1) is mounted in such a way that the drive means can move it in the conveying direction, in both directions (K) with respect to the mobile means themselves;

-at least one of the fixed elements (16b … … 16n-1) is mounted in such a way that it can be moved in a vertical direction (z) by a drive means (39); said movement making it possible to return the mobile device (6, 6a) in the opposite direction to the direction of conveyance (F, F2) and then to pass over the plate in position on the table (5); some of the fasteners, designated (162), have been raised to a specified height in direction (z) so as not to interfere with the plate, while some of the fasteners, designated (161), have been traversed in horizontal direction (H) to a lateral position beyond the area occupied by the plate.