EP2463114A1

EP2463114A1 - Method for processing a brushed, glazed or mirror plate and plant for the obtainment thereof.

Info

Publication number: EP2463114A1
Application number: EP11192391A
Authority: EP
Inventors: Loredana Brunelli; Giuseppe Bonini; Andrea Bonini; Alessio Bonini
Original assignee: Metal Riv Srl
Current assignee: Metal Riv Srl
Priority date: 2010-12-09
Filing date: 2011-12-07
Publication date: 2012-06-13
Anticipated expiration: 2031-12-07
Also published as: ITVR20100234A1; EP2463114B1; IT1403059B1; TR201802435T4

Abstract

The present invention relates to a method for processing a plate (1) having a front brushed, glazed or mirror surface (1 a) and a rear surface (1 b), the method comprising an incision operation at pre-selected zones (2) of the rear surface (1b), involving a simultaneous localized heating of the zones (2), so as to cause a respective controlled permanent alteration of the front brushed, glazed or mirror surface (1a) at the incised zones (2), so as to produce a desired optical effect on such surface.

Description

The present invention regards a method for processing a plate with a brushed, glazed or mirror surface, as well as plant for obtaining such method.
Various methods are known for processing a glazed or mirror plate aimed to obtain a decoration, inscription or the like on the main mirror surface.
The solutions known to the applicant of the present application for treating mirror plate surfaces in order to obtain desired decorations or optical effects on the mirror involve carrying out complex procedures, the use of costly equipment, as well as the use of polluting materials, which at the end of the procedure must be eliminated from the mirror and disposed of.
The German patent document DE-44 41 337 discloses a method for processing a plate, in which a pattern is applied onto a steel plate by means of a laser source designed to irradiate the plate and generate engraved parts.
The main object of the present invention is to provide a method for processing a plate with a brushed, glazed or mirror surface in order to obtain a light, but permanent alteration of the brushed, glazed or mirror surface in accordance with desired configurations that adorn the mirror.
Another object of the present invention is to provide a method for processing a plate with a brushed, glazed or mirror surface which is relatively simple and easy to obtain.
Another object of the present invention is to provide a plant for obtaining the processing method mentioned above which is efficient and does not require large investments.
According to a first aspect of the present invention, a method is provided for processing a plate having a front brushed, glazed or mirror surface and a rear surface. The process comprises an incision operation at pre-selected zones of the rear surface, involving a simultaneous localized heating of the zones so as to cause a respective controlled permanent alteration of the front brushed, glazed or mirror surface at the incised zones, such alteration producing a desired optical effect on such brushed, glazed or mirror surface.
According to another aspect of the present invention, a plant is provided for carrying out a processing method according to the present invention, comprising means for sequentially feeding plates at set intervals, each plate having a front brushed, glazed or mirror surface and a rear surface, as well as an incision station for the rear surface of each plate.
According to another aspect of the present invention, a plate is provided with a front brushed, glazed or mirror surface and a rear surface processed in a plant as defined above, the plate having an optical alteration on the front brushed, glazed or mirror surface and, on the processed rear surface, a plurality of parallel incisions and/or a plurality of incisions with wavy progression and/or a first plurality of a parallel rectilinear incisions and a second plurality of parallel rectilinear incisions that are tilted with respect to the first plurality of incisions.
Further aspects and advantages of the present invention will be clearer from the following detailed description of specific embodiments of the processing method described above, such description being made with reference to the accompanying drawings, in which:

Figures 1 - 6 are plan views of the rear surface of the same number of plates that have been differently processed according to the method of the present invention;
Figure 7 is a cross section view, in enlarged scale, taken at an incision made in the rear surface of a plate processed according to the present invention; and
Figure 8 is a schematic side view of a processing plant according to the present invention.

In the drawing set, equivalent or similar parts or components were marked with the same reference numerals.
The method according to the present invention is aimed towards processing a plate 1 having a front brushed, glazed or mirror surface 1a and a rear surface 1b. It consists of an incision operation at pre-selected zones 2 of the rear, non-mirror surface 1b of the plate 1 and involves the simultaneous localized heating of the incised zones 2, so as to determine a corresponding controlled permanent alteration of the front brushed, glazed or mirror surface 1a at the incised zones 2, thereby producing a desired optical effect on such surface.
The term "incision" in the present description and in the claims indicates a processing for removing material by means of a process tool, such as an abrasive or cutting disc or grindstone or a water-jet device, in order to produce one or more relatively narrow slots (or incisions) on the (non-mirror) rear of a plate 1. The cutting grindstone preferably has a diameter in the range of 125 to 230 mm and a thickness in the range of 1 mm to 3.2 mm.
The method according to the present invention makes it possible to carry out a processing on a plate 1 with effects that are in part of mechanical nature, such as a substantial reduction of thickness due to the removal of material at the incised zone(s), and in part thermally induced due to the removal action of the removal disc(s) (engravers). This leads to a weakening or in any case to an alteration or very slight bending of the brushed, glazed or mirror surface 1a from the other side of the plate 1. Such alteration is desired and detectable by the eye since it locally modifies the reflectance of the brushed, glazed or mirror surface 1 a with respect to the other zones not affected by the processing.
The localized heating is predominantly caused by the employed incision tool, typically one or more motorized abrasive discs, grindstones or cutters, as will be illustrated in detail below.
A plate 1 that can be processed according to the process of the present invention is preferably obtained from a material selected from the group constituted by stainless steel AISI 304BA, 430BA, 316, 316L, 304 Super mirror, aluminum alloy EN 6082, 5084, 5545, 1050, 2024, 5005, 5052, 5754, 5083, 6082, 7075, brass alloy EN CW 506 L, CW 508 L, CW 509 L, copper alloy EN CW400A E CW024A and bronze alloy EN 1982 (CC482K), EN 1982 (CC493K), glazed steel having a grain from 20 to 5000, preferably between 115 and 130.
Preferably, the plate 1 has thicknesses in the range of 0.5 to 3 mm and still more preferably the incision has a depth in the range of 0.002 to 2.9 millimeters as a function both of the nature of the material that constitutes the plate and its thickness.
Advantageously, the maximum incision depth must be such to ensure that the external brushed, glazed or mirror surface 1a has a thickness of at least 0.1 tenths of a millimeter and typically:

for a plate 1 with thickness equal to about 0.5 mm, the incision can have a depth in the range of 0.01 to 0.04 tenths of a millimeter;
for a plate 1 with thickness equal to about 1 mm, the incision can have a depth in the range of 0.001 to 0.09 tenths of a millimeter;
for a plate 1 with thickness equal to about 1.5 mm, the incision can have a thickness in the range of 0.001 to 1.4 millimeters;
for a plate 1 with thickness equal to about 2 mm, the incision can have a depth in the range of 0.001 to 1.9 millimeters;
for a plate 1 with thickness equal to about 2.5 mm, the incision can have a depth in the range of 0.001 to 2.4 millimeters; and
for a plate 1 with thickness equal to about 3 mm, the incision can have a depth in the range of 0.001 to 2.9 millimeters.

With plates 1 having a thickness greater than 3 mm, it is very difficult (if not impossible) to be able to induce a controlled alteration of the optical characteristics of the mirror surface by means of incision of the opposite non-mirror surface 1 b.
Preferably, the step of incision and simultaneous heating of the incised zones 2 is obtained by means of one or more cutting discs of any suitable type, also diamond discs, e. g. having normal dimensions 125x1x22.23, 125x2x22 or 230x3.2x22.23 mm for portable and non-portable cutting machines.
In the case of a normal portable cutting machine, this can be maintained gripped by the operator for the execution of the incision operation of the rear non-mirror surface 1b. Or the cutting machine can be suitably mounted, slidably and/or rotatably, on a support where the plates 1 to be processed are fed.
Preferably, before proceeding with the incision of the rear wall 2b of the plates 1, a cleaning-polishing operation is carried out of the brushed, glazed or mirror surface 1a for an improved final effect.
The operation of incision of the rear surface 1b typically translates into the obtainment of one or a plurality of incisions or small, parallel rectilinear slots or small slots with wavy progression. Or it translates into a first series of parallel rectilinear incisions and a second series of parallel rectilinear incisions which are tilted or transverse with respect to said first series, or other similar configurations.
With a combination of subsequent cuts of the cutting disc(s), one can carry out a plurality of incisions in the surface 1b, which on the corresponding mirror surface 1a give rise to a mirror surface affected by the same number of very slight bends or (linear) alterations of the optical characteristics of the brushed, glazed or mirror surface 1a. The result is that to the observer, the latter surface appears to be configured with (for example) square zones, rectangular zones, rhombic zones etc. according to a desired design.
With particular reference to the embodiments illustrated in Figures 1 to 6, typical configurations of incisions are illustrated on the rear, non-mirror surface 1 b of plates 1, which correspondingly translate into a visual optical effect on the mirror surface 1a. More particularly, and as an example:

Figure 1 illustrates a square plate 1 with a first series of rectilinear line incisions 2a that are substantially equidistant and parallel to each other and to two opposite sides of the plate, and a second series of incisions 2b with rectilinear columns that are substantially equidistant and parallel to each other and to the other two opposite sides of the plate, the incisions 2b of the second series extending at 90° with respect to those of the first series;
Figure 2 illustrates a square plate with a first series of rectilinear incisions 2c that are substantially equidistant and parallel to each other and tilted about 45° with respect to the two opposite sides of the plate, and a second series of rectilinear incisions 2d parallel to each other and tilted about 90° with respect to the incisions of the first series;
Figure 3 illustrates a square plate with a plurality of incisions 2e with wavy progression which are extended from one side to an opposite side of the plate;
Figures 4 and 5 illustrate square plates with series of incisions 2f, 2g, 2h, 2i similar to those of Figures 1 and 2, respectively, but in which the incisions are parallel to each other but not equidistant from each other; and
Figure 6 illustrates a square plate with a first series of rectilinear incisions 2m substantially equidistant and parallel to each other, as well as tilted about 60° with respect to two opposite sides of the plate, and a second series of rectilinear incisions 2n parallel to each other and tilted about 60° with respect to the other two sides of the plate, so as to obtain a diamond echelon effect.

Very important for the preferred obtainment of the method according to the present invention is the control of the localized heating which depends, among other things, on the angular work speed of the tool, on the work pressure of the tool, which to a certain extent determines the cut depth, and on the nature of the processed material. With plates 1 having relatively small thicknesses, the work pressure of the tool can be very critical, since while it is necessary to make optical alterations, these must be done without damaging the brushed, glazed or mirror surface 1a in an uncontrolled manner from the other side of the plate. For this reason, in practice it is imperative to provide for a cutting machine mounted on a suitable support structure, in a manner such that it can be brought close to the work piece (plate 1) and maintained in work position in a controlled manner; for example, by using a support structure equipped with suitable control means of any suitable type, e. g. of a type usually employed on machine tools, so that it is not deemed necessary to provide a detailed description thereof.
For such purpose, a plant 3 (Fig. 8) can be employed for obtaining a method according to the present invention, which comprises a means for sequentially feeding or conveying plates 1 at set intervals, e. g. like a suitably motorized conveyor belt or a roller 4, a processing station 5 comprising one or more cutting heads, where the rear surface 1b of each plate 1 is incised as specified above, and then a possible cleaning station 6 (which can also provide for a lapping treatment) of the mirror surface 1a of the processed plates. If the cleaning station 6 is provided for, an overturning station 7 is provided for upstream of the same for the processed plates 1, so as to bring the processed rear surface 1 b in abutment against the conveyance means 4. The processing station 5 is a station for obtaining a controlled permanent alteration of the front glazed or mirror surface 1 a, and includes incision means for the rear surface 1 b of each plate 1.
The plant can also comprise, upstream of the processing station 5, a polishing station 8 and then a second overturning station 9, so as to bring the surface 1 a in abutment against the conveyance means 4 before the passage into the processing station 5.
With a plant thus structured, one can industrially process the rear surface 1b of a plate 1 in order to create one or a plurality of incisions 2, which (while they are obtained) cause a corresponding modification in the continuity of the mirror surface 1a on the opposite side of the plate being processed 1. Consequently, there is a modification of the reflectance in the zones affected by the incisions on the back of the plate, and hence a modification of the visual effect of the brushed, glazed or mirror surface. In other words, in the brushed, glazed or mirror surface 1a, a trace will be produced (the "negative") of each incision 2 made on the back. Such trace will constitute a decoration or ornament due to a controlled alteration of the mirror surface 1a in desired specific zones.
Reported below are some experimental results obtained by achieving the method of the present invention with plates 1 made of various materials and in accordance with different processing conditions.

Example 1

A plate made of AISI 304 steel is taken with dimensions 1500x800mm and 1mm thickness, then its rear non-mirror surface is processed with a disc cutting machine having 125 mm diameter and 1 to 3 mm thickness, so as to obtain a plurality of incisions 2 therein.
The machine was preferably manually maneuvered with advancing speed in the range of 150mm/minute - 200mm/minute, in a manner such to apply a pressure on the plate in the range of 1.5kg - 2kg per cm². In such a manner, a (removal) cut depth of 0.02 tenths of a millimeter was obtained, while the disc turned at a work speed in the range of 2800 to 11000 revolutions per minute, preferably 2800 to 6500 revolutions per minute.
The advancing speed and the applied pressure were calculated by means of a device (applied on the machine) which detected the advancing speed on the basis of a metric system and the applied pressure by means of a group equipped with thicknesses and springs mounted in the base of the device.
The residual thickness between the bottom of each incision 2 or mirror surface 1a on average resulted 0.03 tenths of a millimeter. At the mirror surface 1 a, one obtains a decoration with quite visible thin zones, corresponding to the incisions 2 on the back; these zones confer an attractive decorative motif that is an integral part of the mirror.

Example 2

A plate made of AISI 304 steel is taken with dimensions 3000x1600mm and 1.5mm thickness. The same plate is treated by means of a water-jet machine or device, e.g. the device sold by Tecnocut S.p.A. of Levate (Bergamo - Italy) with 50 hp or 60 hp pump. By advancing at a cutting speed in the range of 10mm - 40000 mm per minute, with incision pressure in the range of 50 - 4130 bar, and water consumption equal to 9 liters per minute, the water-jet device allowed obtaining a material removal equal to 0.05 tenths of a millimeter. Together with the water, a granular material could be fed, such as an 80 or 120 mesh abrasive grit, e.g. a quantity from 80 to 600 grams per minute, or olivine could be fed in a quantity from 50 to 440 grams per minute.
A plate 1 processed according to the process of the present invention can be typically used as a decorated mirror according to a desired motif, or as a covering element of furniture pieces or furnishing items in general.
The above-described invention is susceptible to numerous modifications and variants within the protective scope defined by the claims.

Claims

A method for processing a plate (1) having a front brushed, glazed or mirror surface (1a) and a rear surface (1b), characterized in that it comprises an incision operation at pre-selected zones (2) of the rear surface (1b), involving a simultaneous localized heating of said zones (2), so as to cause a respective controlled permanent alteration of said front brushed, glazed or mirror surface (1 a) at said incised zones (2), so as to produce a desired optical effect on such surface.
A method according to claim 1, characterized in that said plate (1) is obtained in a material selected from the group constituted by stainless steel AISI 304BA, 430BA, 316, 316L, 304 Super mirror, aluminum alloy EN 6082, 5084, 5545, 1050, 2024, 5005, 5052, 5754, 5083, 6082, 7075, brass alloy EN CW 506 L, CW 508 L, CW 509 L, copper alloy EN CW400A E CW024A and bronze alloy EN 1982 (CC482K), EN 1982 (CC493K), glazed steel having a grain from 20 to 5000, preferably between 115 and 130.
A method according to claim 1 or 2, characterized in that said plate (1) has thicknesses in the range of 0.5 to 3 mm.
A method according to claim 3, characterized in that said incision operation is carried out with a penetration depth in the range of 0.002 to 2.9 mm.
A method according to any preceding claim, characterized in that said incision operation and simultaneous localized heating operation is obtained by means of a cutting disc or grindstone.
A method according to claim 5, characterized in that said cutting disc or grindstone is maneuvered with advancing speed in the range of 150mm/minute to 200mm/minute, so as to apply a pressure in the range of 1.5kg to 2kg per cm².
A method according to claim 5 or 6, characterized in that said disc is mounted for rotation and made to turn at a speed in the range of 2800 to 11000 revolutions per minute.
A method according to any preceding claim 1 to 4, characterized in that said incision operation and simultaneous localized heating operation is obtained by means of a water-jet device.
A method according to any preceding claim, characterized in that it comprises a polishing operation of said front brushed, glazed or mirror surface (1a) before said incision operation.
A plant for obtaining a processing method according to any preceding claim, characterized in that it comprises means (4) for sequentially feeding plates (1) at set intervals, each plate having a front brushed, glazed or mirror surface (1a) and a rear surface (1b), and a station (5) for obtaining a controlled permanent alteration of said front brushed, glazed or mirror surface (1a) including incision means for the rear surface (1b) of each plate (1).
A plant according to claim 10, characterized in that it comprises a cleaning station (6) for each plate (1) processed in said incision station (5).
A plate with a front brushed, glazed or mirror surface (1a) and a rear surface processed in a plant according to claim 10 or 11, having:
- an optical alteration on said front brushed, glazed or mirror surface (1a), and

- on said processed rear surface (1b), a plurality of parallel incisions and/or a plurality of incisions with wavy progression (2e) and/or a first plurality of parallel rectilinear incisions (2a, 2c, 2f, 2h, 2m) and a second plurality of parallel rectilinear incisions (2b, 2d, 2g, 2i, 2n) that are tilted with respect to said first plurality of incisions (2a, 2c, 2f, 2h, 2m).