EP2730381A1

EP2730381A1 - Machine for cutting wood panels or the like

Info

Publication number: EP2730381A1
Application number: EP13186040.5A
Authority: EP
Inventors: Lorenzo Lattanzi
Original assignee: Biesse SpA
Current assignee: Biesse SpA
Priority date: 2012-09-25
Filing date: 2013-09-25
Publication date: 2014-05-14
Also published as: ITBO20120519A1

Abstract

A machine for cutting wood panels (2) or the like is provided with a feeding device (25) for feeding the panels (2) along a support table (P) and through a cutting station (16), with a pressing device (23) for blocking the panels (2) in the cutting station (16), and with a control unit (36) for detecting the presence of foreign bodies in each free area (37a, 37b) between the support table (P) and the pressing device (23) and, therefore, not occupied by the panels (2).

Description

The present invention relates to a machine for cutting wood panels or the like.
It is known in the field of processing wood panels, to provide a cutting machine comprising a support structure defining a substantially horizontal support table for at least one wood panel or the like; a cutting station; at least one feeding device for feeding the panels along the support table and through the cutting station in a given first direction; and a cutting device, which is mounted in the cutting station to move in a second direction and along a cutting plane perpendicular to the first direction, and to cut the panels.
The cutting machine further comprises a pressing device, which is mounted in the cutting station to move perpendicularly to the support table, between a clamping position to clamp the panels against the support table, and a release position; and a safety system for controlling the access of operators to the cutting station.
The safety system generally comprises an emergency bar, which extends above the support table in the second direction, is arranged downstream of the support table in the first direction, and is hooked to the pressing device so as to be arranged at a given distance from the panels when the pressing device is in its clamping position.
The emergency bar is further coupled to the pressing device to move, with respect to the pressing device itself, between a lowered resting position and a raised operating position. The emergency bar is moved in its raised operating position by an operator's hand caught between the panels and the pressing device so as to control at least the stopping of the cutting device and the raising of the pressing device itself.
The safety system further comprises a plurality of substantially flat oscillating flaps, which define a safety curtain, are mounted downstream of the cutting plane in the first direction, are distributed above the support table in the second direction, and are mounted to oscillate about an axis of fulcrum parallel to the second direction.
The flaps are normally arranged in respective lowered positions, in which the flaps are substantially arranged in contact with the support table so as to prevent access to each free area between the support table and the pressing device, i.e. not occupied by the panels, and are tilted so as to selectively move in respective raised positions under the bias of the panels fed through the cutting station.
Known safety systems of the above-described type have certain drawbacks.
The emergency bar is relatively long and thus is subject to bending and requires several frequent adjustments of its position with respect to the pressing device. Furthermore, the emergency bar generally consisting of an aluminium extruded piece extending over the whole width of the support table, may come in contact with the body parts of the operator possibly present in the cutting station, thus causing injury thereto. Finally, the emergency bars are to be manufactured in a number of models corresponding to the different widths of the cutting machine.
The oscillating flaps can be voluntarily raised by operators or can be removed and not replaced in the event of breakage, thus allowing access to each free area between the support table and the pressing device and not occupied by the panels.
It is the object of the present invention to provide a machine for cutting wood panels or the like, which is free from the above-described drawbacks and is simple and affordable to be implemented.
According to the present invention, there is provided a machine for cutting wood panels or the like as claimed in the appended claims.
The present invention will now be described with reference to the accompanying drawings, which show a non-limiting embodiment thereof, in which:

figure 1 is a diagrammatic perspective view, with parts removed for clarity, of a preferred embodiment of the cutting machine of the present invention;
figure 2 is a diagrammatic plan view, with parts removed for clarity, of a detail of the cutting machine in figure 1;
figure 3 is a diagrammatic front view, with parts removed for clarity, of the detail in figure 2; and
figure 4 is a diagrammatic side view, with parts removed for clarity, of the detail in figure 2.

With reference to figure 1, numeral 1 indicates, as a whole, a cutting machine for cutting wood panels 2 or the like, which are substantially rectangular in shape.
Machine 1 has a support structure 3 comprising two portal frames 4 parallel to each other, each of which extends in a horizontal direction 5, and comprises two vertical uprights 6, 7 parallel to each other, which extend in a direction 8 transverse to direction 5, are aligned to the corresponding uprights 6, 7 of the other frame 4 in a horizontal direction 9 orthogonal to directions 5 and 8, and are connected to each other at the upper ends thereof by a horizontal longitudinal member 10 parallel to direction 5.
The two frames 4 are connected to each other by two crosspieces 11 parallel to each other extending between the uprights 6 parallel to direction 9, and by a crosspiece 12 extending between the uprights 7 parallel to direction 9.
Structure 3 further comprises two support devices 13, which are arranged on opposite sides of crosspiece 12 in direction 5, define, together with the upper face of crosspiece 12, a substantially horizontal support table P for panels 2, and comprise one (hereinafter indicated by 13a) a plurality of wheeled bars 14 parallel to one another and to direction 5, and the other (hereinafter indicated by 13b) four tables 15 parallel to one another and to direction 5 itself.
In this regard, it is worth mentioning that device 13a defines a station for loading the panels 2 into machine 1 and that device 13b defines a station for unloading the panels 2 from machine 1.
Machine 1 further comprises a cutting station 16, which is obtained at the uprights 7, and is equipped with a cutting device 17 comprising a motorized carriage 18 coupled in a known manner to a guide 19 which is fastened to the uprights 7 parallel to direction 9 to perform, with respect to structure 3 and under the bias of a known drive device (not shown), straight movements in direction 9.
Carriage 18 supports a blade 20 and an engraver 21 which are mounted to rotate about respective longitudinal axes which are parallel to each other and to direction 5, and to perform straight movements in direction 8 between corresponding lowered resting positions, in which blade 20 and engraver 21 are arranged below table P to allow the feeding of panels 2 along table P, and corresponding raised operating positions, in which blade 20 and engraver 21 project through crosspiece 12 above the table P itself to cut the panels 2.
Blade 20 and engraver 21 are also moved by carriage 18 along a cutting plane 22 which is parallel to direction 9 with a straight alternating motion comprising an advancing stroke, where engraver 21, which is arranged in front of blade 20 in the advancing direction 9 of carriage 18, engraves the panel 2 arranged on table P and blade 20 cuts the panels 2, and a return stroke.
Device 17 cooperates with a pressing device 23 comprising two plates 24, which extend above table P in direction 9, are arranged on opposite sides of plane 22 in direction 5, and are slidingly coupled to the uprights 7 to perform, with respect to the uprights 7 and under the bias of a known drive device (not shown), straight movements in direction 8 from and to a lowered operating position, in which the panels 2 are blocked on table P and are cut by device 17 parallel to direction 9.
Machine 1 further comprises a pick and transport unit 25 for feeding the panels 2 along table P and through station 16 in both the ways of direction 5.
Unit 25 comprises a motorized support crosspiece 26, which extends between the two longitudinal members 10 in direction 9, is slidingly coupled to the two longitudinal members 10 to perform, with respect to the longitudinal members 10 and under the bias of a known drive device (not shown), straight movements in direction 5, and supports a plurality of picking members 27 distributed along the crosspiece 26 in direction 9.
Each member 27 is arranged between two adjacent bars 14, is movable with respect to crosspiece 26 between a raised resting position and a lowered operating position, and comprises two jaws which are movable with respect to each other between a clamping position and a release position of at least one panel 2.
According to a variant (not shown), unit 25 is eliminated and panels 2 are manually fed along table P and through station 16.
Machine 1 further comprises a safety system 28 for controlling the access of operators to the cutting station 16.
In this case, system 28 comprises an optical device 29, which is mounted on the opposite side of device 13a with respect to the cutting plane 22 in direction 5, and is hooked to the pressing device 23 to move in direction 8 following the same law of motion as the plates 24.
In this case, device 29 comprises a sender 30 of a laser beam 31 and a receiver 32 of the laser beam 31 generated by sender 30.
Sender 30 and receiver 32 are arranged on opposite sides of table P in direction 9, are connected to the plates 24 by means of respective supporting brackets 33, and are accommodated in respective channels 34, which are obtained inside the uprights 7 in direction 8, and communicate with the outside through respective slits 35 obtained through the uprights 7 in direction 9.
Furthermore, it is worth mentioning that sender 30 and receiver 32 are hooked to the plates 24 so that, when the pressing device 23 is moved to its lowered operating position, the laser beam 31 is arranged at a certain distance from the panels 2 such as to allow the presence of an operator's hand caught between panels 2 and device 23 to be detected.
According to certain variants (not shown), device 29 is eliminated and replaced, for example, by an optical video camera, a photocell, a thermal sensor, a thermal video camera, or an ultrasound device.
System 28 further comprises a control unit 36 adapted to detect the presence of foreign bodies in each free area between table P and device 23 and not occupied by the panels 2.
In this regard, it is worth mentioning that the term "free area" indicates each area that is not occupied by the panels 2, is restricted in direction 8 by table P and by a plane parallel to table P and tangent to the lower ends of plates 24, and extends downstream and/or upstream of plane 22 in direction 5.
In the case shown in figures 2 and 3, unit 25 feeds two stacks of panels 2 defining two free areas 37a, 37b through station 16; area 37a is defined between the two stacks of panels 2 and area 37b is defined between one of the stacks of panels 2 and the adjacent upright 7.
Unit 36 comprises, for each area 37a, 37b, a respective optical viewing device, in this case a video camera 38 secured to a corresponding upright 7 above table P to detect the presence of foreign bodies in the corresponding area 37a, 37b.
The video camera 38 is mounted on the opposite side of device 13a with respect to the cutting plane 22 in direction 5, and is hooked to the corresponding upright 7 outside the plates 24 in direction 5 or, alternatively, between the plates 24.
The video cameras 38 obviously need to have a field of action which is limited to the corresponding areas 37a, 37b to prevent the presence of panels 2 being mistaken for the presence of foreign bodies.
According to variants (not shown), the video cameras 38 are eliminated and replaced, for example, with a laser scanner or a photocell barrier.
The safety system 28 has certain advantages mainly due to the fact that:

device 29 does not require particular adjustments, is completely mounted outside the support table P and, therefore, is only slightly affected by the processing chips and/or scraps generated when the panels 2 are cut, is used on a single model regardless of the different widths of machine 1, and lastly allows the processing of corrugated panels 2; and
the control unit 36 allows the presence of foreign bodies to be accurately detected in the free areas 37a, 37b, i.e. in the areas not occupied by the panels 2, and to safely stop machine 1.

Claims

A machine for cutting wood panels (2) or the like, the machine comprising a support structure (3) defining a support table (P) for the panels (2); a cutting station (16), the panels (2) being fed along the support table (P) and through the cutting station (16) in a first direction (5); a cutting device (17), which is mounted in the cutting station (16) so as to move in a second direction (9), which is transverse to the first direction (5), and to cut the panels (2); a pressing device (23), which is mounted in the cutting station (16) so as to move in a third direction (8), which is orthogonal to said first and second direction (5, 9), between a clamping position, in which the panels (2) are clamped against the support table (P), and a release position; and a safety system (28) for controlling the access of the operators to the cutting station (16); and being characterised in that the safety system (28) comprises a control unit (36) for detecting the presence of foreign bodies in each free area (37a, 37b) comprised between the support table (P) and the pressing device (23) and, therefore, not occupied by the panels (2).
A machine according to claim 1, wherein the cutting device (17) is mobile along a cutting plane (22) in the second direction (9); each free area (37a, 37b) extending downstream and/or upstream of the cutting plane (22) of the panels (2) in the first direction (5).
A machine according to claim 2, wherein the control unit (36) is mounted downstream and/or upstream of the cutting plane (22) of the panels (2) in the first direction (5).
A machine according to claim 2 or 3, wherein the pressing device (23) comprises two plates (24), which are mounted on opposite sides of the cutting plane (22) in the first direction (5); the control unit (36) being mounted outside of the plates (24) in the first direction (5) or between the plates (24) themselves.
A machine according to any of the previous claims, wherein the control unit (36) comprises, for each free area (37a, 37b), an optical or thermal device (38) for detecting the presence of foreign bodies in the free area (37a, 37b) itself.
A machine according to any of the previous claims, wherein the safety system (28) comprises, furthermore, an optical or thermal or ultrasound device (29), which is suited to generate at least one safety barrier (31), which extends above the support table (P) in the second direction (9) so as to detect the presence of foreign bodies above the panels (2), and is hooked to the pressing device (23) so as to move in the third direction (8) with a law of motion that is identical to a law of motion of the pressing device (23).
A machine according to claim 6, wherein the cutting device (17) is mobile along a cutting plane (22) in the second direction (9); the safety barriers (31) being arranged downstream and/or upstream of the cutting plane (22) of the panels (2) in the first direction (5).
A machine according to claim 6 or 7, wherein the optical or thermal or ultrasound device (29) is hooked to the pressing device (23) so that the safety barrier (31) is arranged at a given distance from the panels (2) when the pressing device (23) is in its clamping position.
A machine according to any of the claims from 6 to 8, wherein the cutting station (16) presents two vertical uprights (7), which are mounted on opposite sides of the support table (P) in the second direction (9) so as to support the cutting device (17); the optical or thermal or ultrasound device (29) being engaged in a sliding manner inside at least one channel (34), which is obtained through at least one of the uprights (7) in the third direction (8).
A machine according to claim 9, wherein each channel (34) is obtained inside the relative upright (7) and communicates with the outside through a slit (35), which is obtained through the upright (7) itself in the second direction (9).
A machine according to any of the claims from 6 to 10, wherein the optical device (29) comprises a video camera or a sender (30) and a receiver (31), which are arranged on opposite sides of the support table (P) in the second direction (9) and are aligned with one another in the second direction (9) itself.
A machine according to any of the claims from 6 to 11, wherein the thermal device comprises a thermal video camera or a thermal sensor.
A machine according to any of the previous claims and comprising, furthermore, at least one feeding device (25), which is mobile along the support structure (3), for moving at least one panel (2) along the support table (P) and through the cutting station (16) in the first direction (5).