DE202006021021U1 - Working space with laser processing device and workspace separation and laser beam reflector for this purpose - Google Patents

Abstract

Working space with a laser processing device (3) in the working space interior (2) and with a working space separation (7, 19) between the working space interior (2) and the working space environment (8), characterized in that the working space separation (7, 19) on their Laser processing device (3) facing inside a laser beam reflector (12, 20), by means of which the predominant part of the laser beam reflector (12, 20) incident and from the laser processing device (3) originating laser radiation is reflected, wherein the laser beam reflector ( 12, 20) is formed diffusely reflecting.

Description

The invention relates to a work space with a laser processing device in the working space interior and with a working space separation between the working space interior and the working space environment. The invention further relates to a working space separation of the type mentioned and a laser beam reflector for this purpose.

Work rooms in which laser processing facilities are operated, in particular for reasons of occupational safety against their environment shield. According to the relevant safety regulations, it must be ensured that, inter alia, even in the event of irregular operating states of the laser processing device and for at least a limited period of time, no harmful laser radiation can escape from the working chamber interior into the working environment. For this purpose, working space separations, so-called "laser protection walls" are used.

A generic work space and a generic work space separation are disclosed in US 4,650,287 A , In the case of the prior art, a working space accommodating a laser processing machine is enclosed by a radiation-absorbing laser protective wall. In the previously known laser protective wall is a composite construction of a metal sheet on the remote from the laser processing machine wall outside and a radiation-absorbing coating, which is applied to the metal sheet on its side facing the laser processing machine inside. The radiation-absorbing coating is formed by metal oxides, for example by aluminum, titanium, zirconium, magnesium and / or chromium oxide. The ability of these metal oxide coatings to absorb laser radiation is described in US Pat US 4,650,287 A referred to as extraordinary.

From US 4,650,287 A As a result, known laser protective wall acts as a radiation trap, which as such absorbs the majority of the energy of the laser radiation to be prevented from leaving the working chamber interior. Consequently, the special heat resistance of the radiation-absorbing metal oxide coatings is emphasized in the prior publication.

The extent of the coupled into the previously known laser protective wall radiation energy has a negative effect on the service life of the laser protective wall under radiation exposure. This in turn impairs the suitability of the previously known laser protective wall as a device of occupational safety.

The object of the present invention is to ensure maximum occupational safety in combination with maximum operational safety of the laser processing device accommodated in the working space in a working space of the type mentioned in the introduction.

This object is achieved according to the invention by the working space according to claim 1, by the working space separation according to claim 16 and by the laser beam reflector according to claim 17.

In the case of the invention, a laser beam reflector is provided on the inside of the working space separation, which reflects the vast majority of the laser radiation to be prevented from leaving the working chamber interior. The high reflectivity of the laser beam reflector according to the invention prevents radiation energy of the laser radiation incident on the laser beam reflector from being coupled into the work space separation to an extent which would lead to overheating and associated destruction of the work space separation after a short time. In this respect, the features of the invention ensure maximum occupational safety.

At the same time, the incident laser radiation is not directed by the laser beam reflector according to the invention but rather diffusely reflected. As a result of their scattering, the reflected laser radiation has only a low energy density and is therefore unable to cause damage in the working space interior, in particular on the laser processing device arranged there. In this respect, the invention provides for maximizing the reliability of the laser processing device. Otherwise protective devices to be used on the laser processing device, such as protective covers for bellows are dispensable.

Both from the point of view of occupational safety and in terms of operational safety of the laser processing device features of the invention are then of particular advantage when working on the laser processing device with laser radiation high power.

Particular embodiments of the invention according to claims 1, 16 and 17 emerge from the dependent claims 2 to 15.

The invention type of construction according to claim 2 is characterized in that the laser beam reflector is matched to the material based on the wavelength of the laser radiation to be reflected. In this way it is ensured that in fact the vast majority of the Laser beam incident laser radiation is reflected. The wavelength of the laser light to be reflected depends on the design of the beam source. For example, at a laser beam reflector made of aluminum, CO ₂ laser light can be reflected to 90%, NdYAG laser light to 90%. In general, laser beam reflectors with a reflectance of at least 90% are preferred according to the invention. With such a degree of reflection of the laser beam reflector can ensure sufficient service life of the workspace separation.

Particularly practical are laser beam reflectors in the form of diffusely reflecting metallic surfaces (claim 3). Such laser beam reflectors can be relatively easily manufactured and show the required reflectivity due to their robustness even under harsh operating conditions and over a long period of use.

As materials for serving as laser beam reflectors metallic surfaces according to the invention various metals in question (claim 4). As a laser beam reflector is preferred in the case of the invention, a diffusely reflecting aluminum surface. Such laser beam reflectors are particularly inexpensive. In addition, the use of aluminum as a reflector material due to its (for example compared to copper) relatively low thermal conductivity and due to its low weight is recommended. Finally, with aluminum - as stated above for claim 2 - at different wavelengths of the laser light to be reflected always achieve a high reflectance.

For the sake of simplicity, in particular in the interest of the simplest possible and cost-effective production, in the case of the invention as the laser beam reflector forming diffuse reflective surface is a bare surface, where appropriate, a bare metallic surface, preferred.

The laser beam reflector, optionally the metal surface forming the laser beam reflector, may be formed by a coating applied to a carrier (claim 6). As a coating method, for example, the flame spraying or metal deposition process come into question.

In the interests of a particularly simple and cost-effective production, it is recommended to provide a laser beam reflector directly a surface of a reflector body (claim 7). The application of a surface coating serving as a laser beam reflector on a support is unnecessary in this case.

In a preferred embodiment of the invention is as a surface with the laser beam reflector forming reflector body, a metal body, in particular a metal sheet provided (claim 8). According to the invention, preference is given to an aluminum sheet which forms the laser beam reflector with a bare and diffusely reflecting aluminum surface.

A diffuse reflection of the incident laser radiation by the laser beam reflector can be effected according to the invention in different ways.

For manufacturing reasons, it is recommended to provide the laser beam reflector with a corresponding spatial surface structure (claim 9). In this case, a particularly intensive scattering of the reflected laser light by means of irregularly profiled surface structures can be achieved (claim 10). Nevertheless, however, laser beam reflectors with a regularly profiled surface structure are also conceivable. For example, by embossing processing, surface structures according to the invention can be produced, in particular, on sheets which form the laser beam reflector directly with their surface.

Commercially available and thus advantageously freely available are grained surface structures (claim 11).

Optimum functionality of laser beam reflectors according to the invention requires their dimensional stability. To ensure this dimensional stability stiffening deformations are provided in the case of Erfindungsbauart according to claim 12 to the provided with a diffusely reflective coating carrier or on which a diffusely reflecting surface forming reflector body. As commercially available and thus readily available carrier or reflector body to offer trapezoidal sheets (claim 13). Stiffeners of the type mentioned are particularly useful when the laser beam reflector is provided in the ceiling area of the working space or the workspace separation.

According to claim 14, a laser beam reflector is part of a working space separation, which also comprises an outer layer, which in turn is disposed on the side remote from the laser processing device side of the laser beam reflector. Appropriately, the laser beam reflector is detachably connected to the outer layer of the working space separation. Because of this detachable connection, for example, a defective or worn laser beam reflector can be exchanged in a simple manner for a fully functional laser beam reflector. Also, one can For example, to perform maintenance, especially cleaning, laser beam reflector easily from the associated outer layer of the workspace separation and attach after maintenance or cleaning back to the outer layer.

In the interest of a thermal insulation of the outer layer of the working space separation against the laser beam reflector remains in the case of Erfindungsbauart according to claim 15 between the laser beam reflector and the outer layer of the working space separation, a gap.

The invention will be explained in more detail below with reference to exemplary and highly schematic representations. Show it:

1 a working space in the form of a laser protection cabin with a laser processing device and a working space separation,

2 the detail II of 1 .

3 the detail III of 1 .

4 a subarea of the workspace separation according to 1 in the perspective view from the working space inside,

5 a sectional view of the workspace separation according to 1 and

6 a sectional view of a second type of workspace separation.

According to 1 accommodates a working room designed as a laser protection cabin 1 in the workspace interior 2 a laser processing device 3 , which in the example shown as a laser cutting device for the 3D machining of workpieces 4 is executed. From a laser cutting head 5 the laser processing device 3 Off is in regular cutting operation, a laser beam 6 on the workpiece to be machined 4 directed.

As in 1 indicated, the laser beam 6 on the surface of the workpiece 4 partially reflected. The from the surface of the workpiece 4 radiated laser radiation hits the inside of a workspace partition 7 , This surrounds the laser processing device 3 Dome-like and shield the working space inside 2 against the workspace environment 8th from. In the workspace environment 8th holds an operator 9 on.

The workspace separation 7 includes a vertical wall area 10 as well as a horizontal ceiling area 11 , Both in the wall area 10 as well as in the ceiling area 11 indicates the workspace separation 7 at her the laser processing unit 3 facing inside a laser beam reflector 12 on. The laser beam reflector 12 is formed from the surface of blanks of aluminum sheet with a thickness of 1 mm. In the ceiling area 11 the workspace separation 7 are provided as sheet metal blanks trapezoidal sheets. Both in the wall area 10 as well as in the ceiling area 11 the workspace separation 7 are the sheet metal blanks with an outer layer or outer shell 13 the workspace separation 7 screwed. The outer shell 13 the workspace separation 7 is made of two millimeters thick sheet steel.

The aluminum sheet of the laser beam reflector 12 is commercially available. In construction, for example, it is used as a façade or roof cladding, among other things. The sheet surface containing the laser beam reflector 12 is bright, and has a spatial surface structure, which in the 2 and 3 is shown hinted. In 1 is the laser beam reflector 12 illustrated for simplicity as a flat surface.

The spatial surface structure of the for the laser beam reflector 12 used aluminum sheet is irregular and corresponds approximately to the surface texture of grained leather. Commercially, this surface structure is available under the name "stucco dessiniert". Alternatively, inter alia, the use of aluminum sheet with regularly structured surface, for example with spherical structures conceivable.

Decisive is the reflection behavior of the sheet metal surface. Firstly, it must be ensured that the laser processing device 3 originating laser radiation at the laser beam reflector 12 forming sheet surface is reflected for the most part. This requirement is made by the laser beam reflector 12 forming bare aluminum surface of the embodiment shown to a high degree. This is how the laser beam reflector reflects 12 about 99% of the incident laser radiation. This extraordinarily high reflectance is achieved at the wavelength of the example shown on the laser beam reflector 12 meeting laser light. The wavelength of the laser light in turn depends on the design of the beam source. For generating the laser beam 6 a CO ₂ generator is used. Would that be the laser beam reflector 12 generates incident laser light by means of a NdYAG laser, so could be achieved with the bare aluminum surface of the embodiment, a reflectance of about 90%. Due to the selected surface structure of the laser beam reflector 12 becomes a reflectance of the order of magnitude even with a usual in the vicinity of laser cutting equipment contamination of the laser beam reflector 12 reached.

Due to the high reflectivity of the laser beam reflector 12 it comes under the action of the laser beam reflector 12 incident laser light to only a slight warming of the laser beam reflector 12 and thus the entire workspace separation 7 , The workspace separation 7 therefore achieves long service life.

At the same time, the surface structure of the laser beam reflector ensures 12 for a diffuse reflection of the incident laser light as seen in the 2 and 3 is indicated. The energy densities in that of the laser beam reflector 12 emitted laser light are therefore at a low level. In particular, the energy densities mentioned are too low to be inside the working space 2 , in particular at the laser processing device 3 Could cause damage. Consequently, for example, otherwise required for protective bellows for bellows of the laser machining device 3 be waived.

The described protective effect inwardly and outwardly unfolds the laser beam reflector 12 even in irregular operating conditions of the laser processing device 3 , about when the laser beam 6 from the laser cutting head 5 accidentally on the laser beam reflector 12 is directed.

4 shows the laser beam reflector 12 on the outer shell 13 the workspace separation 7 in the view of working space inside 2 ago. The illustrated wall area is provided with window cutouts. Clearly visible is the surface structure of the laser beam reflector 12 ,

5 shows a screw connection between the laser beam reflector 12 and the outer shell 13 the workspace separation 7 in detail.

Accordingly, the laser beam reflector 12 by means of a spacer sleeve 14 at a distance from the outer shell 13 held. The resulting gap between the laser beam reflector 12 and the outer shell 13 the workspace separation 7 serves the thermal insulation of the outer shell 13 against the acted upon by laser radiation laser beam reflector 12 , The spacer sleeve 14 is from a bolt 15 interspersed with the outer shell 13 associated longitudinal end with a foot plate 16 is welded. The foot plate 16 is on a self-adhesive blank on both sides 17 glued from sponge rubber. The cut 17 turn is at his from the foot plate 16 distant side with the outer shell 13 bonded. At the free end of the bolt 15 is the laser beam reflector 12 between a mother 18 and the spacer sleeve 14 braced. Corresponding connections between the laser beam reflector 12 and the outer shell 13 the workspace separation 7 are at the other attachment points of the laser beam reflector 12 produced.

For disassembly of the laser beam reflector 12 are either the nuts 18 or the glued joints between the blanks 17 the individual fastening devices and the outer shell 13 to solve. For new installation of the laser beam reflector 12 in the latter case, the old blanks 17 on the foot plates 16 the various fastening devices replaced by new blanks with still unused adhesive surfaces. Subsequently, the laser beam reflector can be 12 on the foot plates 16 applied new blanks 17 on the inside of the outer shell 13 the workspace separation 7 stick on.

6 shows a workspace partition 19 with a laser beam reflector 20 and an outer layer or outer shell 21 , The laser beam reflector 20 is bent at its edge U-shaped. Between two legs of the U-shaped bevel of the laser beam reflector 20 and the outer shell 21 each is a Velcro connection 22 produced. For this purpose, on the one hand to the laser beam reflector 20 and on the other hand, on the outer shell 21 conventional Velcro tape sections attached. The Velcro connections 22 allow a handling-friendly assembly and disassembly of the laser beam reflector 20 ,

Both the laser beam reflector 12 according to 5 as well as the laser beam reflector 20 according to 6 is formed by a "stucco-patterned" surface of aluminum sheet blanks. From a detailed representation of said surface structure was in the 5 and 6 for the sake of simplicity of illustration.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 4650287 A [0003, 0003, 0004]

Claims (17)

Working space with a laser processing device ( 3 ) in the workspace interior ( 2 ) and with a workspace separation ( 7 . 19 ) between the working space interior ( 2 ) and the workspace environment ( 8th ), characterized in that the working space separation ( 7 . 19 ) at its the laser processing device ( 3 ) facing inside a laser beam reflector ( 12 . 20 ), by means of which the predominant part of the laser beam reflector ( 12 . 20 ) and from the laser processing device ( 3 ) laser radiation is reflectable, wherein the laser beam reflector ( 12 . 20 ) is formed diffusely reflecting. Working space according to claim 1, characterized in that the laser beam reflector ( 12 . 20 ) is tuned with respect to its material to the wavelength of the laser radiation to be reflected. Working space according to one of the preceding claims, characterized in that as a laser beam reflector ( 12 . 20 ) A metallic surface is provided, which is formed diffusely reflecting. Working space according to one of the preceding claims, characterized in that as the laser beam reflector ( 12 . 20 ) forming metallic surface of an aluminum and / or a copper and / or a molybdenum and / or a chromium and / or a silver and / or a gold surface is provided, which is formed diffusely reflecting. Working space according to one of the preceding claims, characterized in that as the laser beam reflector ( 12 . 20 ) forming surface, optionally as the laser beam reflector ( 12 . 20 ) forming metallic surface, a bare surface, optionally a bare metallic surface, is provided, which is formed diffusely reflecting. Working space according to one of the preceding claims, characterized in that the laser beam reflector ( 12 . 20 ), where appropriate, the laser beam reflector ( 12 . 20 ) forming metallic surface is formed by a coating applied to a carrier coating. Working space according to one of the preceding claims, characterized in that as a laser beam reflector ( 12 . 20 ) is provided directly a surface of a reflector body. Working space according to one of the preceding claims, characterized in that a metal body, in particular a metal sheet, is provided as the reflector body forming the laser beam reflector directly with its surface. Working space according to one of the preceding claims, characterized in that the laser beam reflector ( 12 . 20 ) is formed diffusely reflecting due to its spatial surface structure. Working space according to one of the preceding claims, characterized in that as a diffusely reflecting spatial surface structure of the laser beam reflector ( 12 . 20 ) an irregularly profiled surface structure is provided. Working space according to one of the preceding claims, characterized in that as a diffusely reflecting spatial surface structure of the laser beam reflector ( 12 . 20 ) A grained surface structure is provided. Working space according to one of the preceding claims, characterized in that the carrier, which with the laser beam reflector ( 12 . 20 ) is provided, or the reflector body, the laser beam reflector ( 12 . 20 ) forms directly with its surface, at least partially has a stiffening deformation. Working space according to one of the preceding claims, characterized in that the carrier, which with the laser beam reflector ( 12 . 20 ) is provided, or the reflector body, the laser beam reflector ( 12 . 20 ) forms directly with its surface, at least partially formed as a trapezoidal sheet. Working space according to one of the preceding claims, characterized in that the laser beam reflector ( 12 . 20 ) with an outer layer ( 13 . 21 ) of the workspace separation ( 7 . 19 ) is releasably connected, wherein the outer layer ( 13 . 21 ) of the workspace separation ( 7 . 19 ) at the of the laser processing device ( 3 ) facing away from the laser beam reflector ( 12 . 20 ) is arranged. Working space according to one of the preceding claims, characterized in that the laser beam reflector ( 12 . 20 ) forming a gap between the laser beam reflector ( 12 . 20 ) and the outer layer ( 13 . 21 ) of the workspace separation ( 7 . 19 ) with the outer layer ( 13 . 21 ) of the workspace separation ( 7 . 19 ) connected is. Working space separation for a work space ( 1 ) with a laser processing device ( 3 ), characterized by the on the workspace separation ( 7 . 19 ) related features of at least one of the preceding claims. Laser beam reflector for a workspace separation ( 7 . 19 ) of a workroom ( 1 ) with a laser processing device ( 3 ), characterized by which the laser beam reflector ( 12 . 20 ) related features of at least one of claims 1 to 15.

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