EP1772238B1

EP1772238B1 - Device for finishing metal edges fitted to panels

Info

Publication number: EP1772238B1
Application number: EP06122029A
Authority: EP
Inventors: Mauro Sandon
Original assignee: Fravol Export Srl
Current assignee: Fravol Export Srl
Priority date: 2005-10-10
Filing date: 2006-10-10
Publication date: 2008-07-02
Anticipated expiration: 2026-10-10
Also published as: ITPD20050292A1; ATE399622T1; EP1772238A1; DE602006001619D1

Abstract

Device for finishing metal edges (B) fitted to wood panels (P), comprising a surface finishing tool able to treat at least one milled zone of the metal edge. The tool consists of an idle roller (6) with an external incision surface able to rotate in contact with the zone of the edge so as to impress on it a mark when the panel is displaced with a relative movement with respect to the device in a feeding direction.

Description

The present invention relates to a device for finishing metal edges fitted to panels made of wood or the like.
More specifically, the device in question is intended to perform a machining operation consisting in joining and rounding the corners which delimit the sides of the panels.
The device may be advantageously mounted on a dedicated machine or may be provided on panel edging machines equipped with various working units arranged in series and comprising, for example, end-butting, milling, sanding, gluing, trimming or other units.
In the wood processing industry, and in particular in the furniture industry, it is customary to line panels by fitting edges which are then finished, rounding off their corners with the desired profiles.
For this purpose, edging machines are known to exist on the market, these machines being provided with automatic devices which have a milling tool able to follow the panels during their travel between an entrance way and an exit way and perform edging of the corners of the sides after the latter have been fitted.
For example, the Italian patent application No. IT MI99A002342 in the name of the same applicant discloses an automatic device for milling bases on panels, which has two separate milling tools able to perform machining of the front and rear edge of the panel, respectively, each being able to travel along an inclined surface so as to follow the panel during its displacement and rotate by means of a support rotatable through 180 degrees so as to allow complete machining of the panels edges.
At present, for mainly aesthetic reasons, an increasingly important and growing market is that of wood panels (or panels made of similar material) which are finished with metal edges in particular made of aluminium. The metal edge, in addition to having improved mechanical strength, scuff resistance and abrasion resistance properties, is particularly valued from a purely aesthetic point of view owing to the metallic effect which it gives to the panel.
The edges are satinized and anodized or suitably treated so as to provide the aesthetic effect and, in particular, the desired lustre.
As is known, satinizing and anodization are performed in zones formed in the peripheral part of the edges where the latter are machined with milling tools so as to obtain the desired joining angle with the panel surface.
These smoothed zones are left visible. The mechanical milling operations have the effect of rendering the surfaces glossy, reflective and often not entirely uniform.
In order to overcome this drawback, at present edging machines with devices for finishing metal edges have been envisaged, said devices being provided with smoothing tools consisting of abrasive-paper belts able to eliminate the surface effect of mechanical machining, namely the undulations and lustre of the treated zones, providing them again with a satinized or similar appearance.
The main disadvantage of this technique consists in the fact that the aluminium smoothing operations are very complex and require the use of a tool specially designed for the purpose and in particular an abrasive belt which must be replaced very frequently since it has a very limited wear.
Tools consisting of brushes with abrasive-paper lamellae have also been used, which tools, although bettering the performance of abrasive belts, have never achieved satisfactory results in terms of duration. These brushes, moreover, have proved to have the drawback that they ruin the satinized surfaces of the panel owing to the deformation which they undergo during treatment of the panel and owing to their wear which ultimately results in some of their deformed parts interfering with the satinized surfaces of the panel, i.e. both of the edge and of the laminated parts.
Further drawbacks of the devices used hitherto to treat the zones of the edges subject to joining machining operations are the high volume, excessive cost, high maintenance and contamination with aluminium powders which are difficult to remove.
A further drawback consists in the fact that the devices with the tools described above are suitable for treating exclusively the upper and lower zones of the edges while the panels advance through conventional edging machines.
In fact, these tools are unable to treat the vertical zone of the edges which, remaining glossy and non-uniform as a result of the abovementioned milling operations, prevent optimum qualitative standards being achieved. In this situation, the main object of the present invention is therefore to overcome the drawbacks associated with the devices of the known type by providing a device for finishing metal edges fitted to wood panels, which allows the milled zones to be treated in a simple and low-cost manner.
Another object of the present invention is to provide a device which allows any milled zone of the edge of the panel to be treated, providing it with a lustre and a surface appearance substantially similar to that of the non-milled parts of the edge.
A further object of the present invention is to provide a device which has small dimensions.
Another object of the present invention is to provide a device which is constructional simple and operationally entirely reliable.
The invention is defined in the appended claims. The advantages of the invention will emerge more clearly from the detailed description which follows, provided with reference to the accompanying drawings which show some purely exemplary and non-limiting embodiments thereof, where:

Figure 1 shows schematically a general view of a series edging machine with, mounted thereon, a device for finishing metal edges fitted to wood panels, according to a first embodiment of the invention;
Figure 2 shows schematically a front end view of the device according to Figure 1;
Figure 3 shows schematically a side view of the device according to Figure 1;
Figure 4 shows schematically a first perspective view of the device according to Figure 1;
Figure 5 shows schematically a second perspective view of the device according to Figure 1;
Figure 6 shows schematically a front end view of a second embodiment of the device for finishing metal edges fitted to wood panels according to the invention;
Figure 7 shows schematically a side view of the device according to Figure 6;
Figure 8 shows schematically a perspective view of the device according to Figure 3.

With reference to the accompanying drawings, 1 denotes in its entirety a device for finishing metal edges fitted to wood panels according to the present invention.
The device 1 in question may be arranged on machines A for edging panels P arranged in series with other working units such as an end-butting unit, a milling unit, a sanding unit, a gluing unit, a trimming unit or other units.
In accordance with the example of embodiment illustrated in Figure 1 this device 1 is arranged downstream of a trimming device 2 which can be inclined at an angle of between 0° and 45° by means of motors rotated through 90° for machining operations using end milling cutters on zones F of the edge B of the panels P and downstream of a device/assembly of inclinable brushes 3 for cleaning the panels P.
The device 1 is intended to treat the zones F of the metal edge B of a panel P, in particular made of chipboard, MDF or the like, in order to eliminate the surface effect of mechanical machining, i.e. the undulations and the lustre so as to provide again these zones F with a satinized or similar appearance. The device 1 according to the invention comprises essentially a support structure 4, with a support base for receiving the panel, which may be in common with that of the edging machine A on which the device 1 is mounted. In this case, this common support structure is provided with means for feeding the panels P, for example consisting of a track-type conveyor belt 5 which is per se of the conventional type and able to cause feeding of the individual panels P in a horizontal position and in succession between an entrance way and an exit way.
In accordance with the idea underlying the present invention it is envisaged providing a tool 6 formed by a roller supported in an idle manner on the support structure 4 and provided with an external incision surface able to rotate in contact with the zone F the edge B so as to impress a mark on it when the panel P passes through the device 1 following displacement of the panel P or the said device 1.
In order to allow the correct positioning of the marking roller 6, a vertical coupling device 7, consisting preferably of an idle roller with a horizontal axis able to rest on the upper or lower surface of the panel P, is advantageously provided.
The mark is obtained by pushing the idle roller 6 with a pressure in the range of between 5 and 50 kg (50 to 500 N) and preferably between 10 and 15 kg (100 to 150 N) against the metal edge B of the panel P. The roller 6 is provided with an external incision surface which undergoes treatment involving a double coating of titanium in order to reduce the friction and increase the working life of the marking roller 6.
For the sake of simplicity of manufacture the surface of the roller 6 may be simply provided with a thread or channels parallel to the lathe, for example preferably with a pitch of two tenths of a millimetre and depth of 7 hundredths of a millimetre.
The device comprises a support 8 on which the idle roller 6 is mounted. The support is pivotably mounted on the support structure 4 and may be made to rotate in an adjustable manner about an axis X' parallel to the feeding direction X in order to provide the roller 6 with an inclination preferably at an angle of between 5° and 45° and similar to that of the surface of the zone on the edge of the panel as obtained by the above milling tool 2 shown in Figure 1.
In greater detail, the support 8 and the idle roller 6 are connected to the support structure 4 via a plate 9 acted on by spring means 10 able to push the idle roller 6 against the zone F of the edge B to be treated.
The device for finishing metal edges indicated by 1 in Figures 6-8 envisages a support structure 4 with means provided for feeding the panels for example consisting of a track-type conveyor belt which is per se of the conventional type, able to cause feeding of the panels individually and in a horizontal position, in succession with respect to each other between an entrance way and an exit way of the device 1.
A movable carriage 11 with a finishing unit 13 mounted thereon is actuated so as to be displaced by a first motor 12, over a suitable displacement path in a feeding direction X parallel to the direction of the panel P, along a first guide G formed on the support structure 4.
For this purpose the first motor 12 (preferably a worm gear motor) is connected to the carriage 11 via flexible drive means. The latter advantageously consist of a chain wound endlessly around a driving wheel, a tensioning wheel and two transmission wheels.
The first motor 12 advantageously consists of a normal asynchronous motor which is therefore available on the market at a low cost. This motor is controlled by an inverter connected to the PLC having an electronic positioning system which is able to control rotation of the rotor with the magnetic poles and therefore, ultimately, control the position of the carriage 11 and the finishing unit 13 along the guide G.
The movement of the panels is assisted by an encoder which is also connected to the PLC and is able to produce a pulsed signal able to operate the inverter of the first motor 12 so that the carriage 11 moves perfectly in synchronism with the panels P.
Consequently the first motor 12 causes displacement of the finishing unit 13 at the same speed as the panels P and therefore this unit, in respect of said displacement, may be regarded as being stationary with respect to the panels.
Alternatively the first motor 12 may be also provided with an encoder connected to the PLC so as to ensure a greater precision during positioning of the finishing unit 13 along its displacement path.
Two mechanical safety end-of-travel stops 90 are nevertheless envisaged for limiting the displacement travel of the finishing unit 13.
The finishing unit 13 is rotatably mounted on the carriage 11 by means of a shaft about the transverse axis Y perpendicular to the direction of feeding X of the movable carriage 11.
According to the invention, the finishing unit 13 has, mounted thereon, the tool 6 described above and consisting of an idle roller with an external incision surface able to rotate in contact with the zone F of the edge B of the panel P so as to impress a mark on the substantially vertical zones F of the said panel while the latter is displaced in the feeding direction X.
From a functional point of view, the finishing unit 13 is actuated so as to rotate about the shaft with a transverse axis Y in a synchronized manner with its displacement above the carriage so as to treat the abovementioned vertical zones of the edges B of the panels.
For this purpose, it is preferable to envisage a second motor 14 integral with the carriage 11 and electrically coupled with the first motor 12 so as to synchronise in predefined operating steps the rotation of the finishing unit 13 with its displacement along the path above the carriage 11. The second motor 14 consists of a worm gear motor controlled by means of an inverter connected to the PLC and provided with a pulsed positioning device for correct angular positioning of the finishing unit 13. Preferably this second rotor 14 is provided with an encoder for ensuring greater precision during angular positioning of the unit 13. More generally, the first motor and/or the second motor may also be controlled by other electrical actuating systems (actuating systems for brushless, DC or other types of motors), without thereby departing from the scope of protection of the present patent.
The finishing unit 13 comprises a support 15 consisting of a plate with a disc-shaped form at the front on which a finishing head 16 with the tool 6, integral therewith, is slidably mounted along second guides 17.
A pneumatic actuator 18 is provided on the support 15 in order to displace the head 16 along the second guides 17 and thus push, with the correct pressure, the tool 6 against the zone F of the edge B of the panel P, allowing the mark to be impressed thereon.
Special coupling devices of the type known per se or within the grasp of any person skilled in the art may be envisaged for correct supporting and centring of the tool 6 on the edge B of the panel to be treated.
As an alternative to the solution described above, the translatory movement of the finishing unit 13 may be mechanically constrained to the rotational movement of the said unit 13 by means of transmission means of the type described, with reference to a milling unit, in European patent 750536 .
With the invention it is possible to treat, in a low-cost manner, all the milled zones of a metal edge, in particular an edge made of aluminium, so as to provide it again with a satinized or similar appearance.

Claims

Device for finishing metal edges fitted to panels made of wood or the like comprising:
- a support structure (4) with a support base for receiving a panel (P) movable through the device (1) in a feeding direction (X);

- at least one surface finishing tool mounted on said support structure (4), able to treat at least one peripheral band (F) of said metal edge (B), having a lustre or undulated surface due to a treatment with mechanical machining;
characterized in that said tool consists of an idle roller (6) supported in an idle manner on the support structure (4), pushed by spring means (10, 18) against said band at a pressure in the range of between 5 and 50 kg (50 to 500 N) and preferably between 10 and 15 kg (100 to 150 N), and provided with an external incision surface having reliefs able to rotate in contact with the band (F) of said edge (B) so as to impress on it by means of said reliefs a mark when said panel (P) is displaced with a relative movement with respect to said device (1), said mark covering the whole band (F) surface to provide them with a satinized or similar appearance.
Device according to Claim 1, characterized in that it comprises at least one vertical coupling device (7).
Device according to any one of the preceding claims, characterized in that it comprises a support (8) having, mounted thereon, said idle roller (6) rotatably pivoted on said support structure (4) in an adjustable manner at an angle of between 5° and 45° about an axis (X') parallel to the feeding direction (X).
Device according to claim 3, characterized in that it comprises a plate (9) with, mounted thereon, said support (8) and said idle roller (6), mechanically connected to said support structure (4) by means of said spring means (10) able to push said idle roller (6) against the band (F) of said edge to be treated.
Device according to any one of the preceding claims, characterized in that said external incision surface is provided with a thread or parallel channels.
Device according to any one of the preceding claims, characterized in that said external incision surface is a steel surface with a multi-layer titanium coating.
Device according to Claim 1, characterized in that it comprises:
- feeding means mounted on said support structure and able to convey with a continuous movement said panel (P) between at least one entrance way and at least one exit way;

- a movable carriage (11) mounted guidably on said support structure (4) and moved by a first motor (12) so as to be displaced parallel to said panel (P) in a feeding direction (X);
a finishing unit (13) rotatably mounted on said carriage (11) about a shaft with an axis (Y) transverse to the direction of feeding (X) of said carriage (11), and provided with said tool (6) to impress on said band (F) the mark while said panel (P) is displaced in said feeding direction (X), said finishing unit (13) being actuated so as to rotate about said shaft with a transverse axis (Y) and being moved in a manner operationally coupled with said first motor (12) so as to synchronise in predefined operating steps the rotation of said finishing unit (13) with the displacement of said carriage (11) carrying said finishing unit (13).
Device according to Claim 7, characterized in that said finishing unit (13) is actuated so as to rotate by a second motor (14) integral with the carriage (11) and electrically coupled with the first motor (12) so as to synchronise in predefined operating steps the rotation of the finishing unit (13) with its displacement along the path above the carriage (11).
Device according to Claim 7, characterized in that said first motor (12) is controlled by an inverter.
Device according to Claim 8, characterized in that said second motor (14) is controlled by an encoder.
Device according to Claim 7, characterized in that said finishing unit (13) comprises a support (15) on which there is slidably mounted along second guides (17) a finishing head (16) having said tool (6) integral therewith, and a linear actuator (18) mounted on said support (4) and able to displace said head (16) along said second guides (17) so as to push said tool (6) against the band (F) of the edge (B) of said advancing panel (P).