DE102011013210A1 - Apparatus and method for processing at least one workpiece - Google Patents

Abstract

The invention relates to a device for processing at least one workpiece (12, 14), which comprises a beam guiding device for guiding a laser beam (2) irradiated into the device, which device comprises a first deflecting mirror (6) for deflecting the irradiated laser beam (2) is mounted rotatably about an axis of rotation, characterized in that the beam guiding device comprises at least one first ring mirror (10) which is arranged such that a laser beam (2) deflected by the first deflecting mirror (6) onto the at least one first ring mirror (10) hits and is reflected.

Description

The invention relates to a device for processing at least one workpiece, which comprises a beam guiding device for guiding a laser beam irradiated into the device, which comprises a first deflecting mirror for deflecting the irradiated laser beam, which is rotatably mounted about a rotation axis.

The invention also relates to a method for processing at least one workpiece, in which at least one laser beam is directed onto at least one region of the workpiece to be machined.

A generic device is for example from the DE 10 2008 022 259 A1 known. The device described here for processing glass components is used, for example, to assemble two cylindrical glass elements to form a long cylindrical element. For this purpose, the two glass components are clamped horizontally and arranged together. The contact area is heated by means of a laser beam, so that it is plastically deformable.

The device described in the cited document is only suitable for joining hollow cylindrical workpieces. The laser beam is conducted by means of a radiation guide into an interior of the workpieces or the glass components and passed there by means of a deflecting mirror from the inside to be heated portions of the glass components. The Strahlungsleitvorrichtung, at which the deflection mirror is, is rotatable about the longitudinal axis, which coincides with the longitudinal axis of the cylindrical glass components, so that the deflection mirror rotates. The area in which the laser beam falls on the inner surface of the components to be joined, thus also rotates. Due to the high rotational speeds of, for example, 1000 revolutions per minute, there is an almost homogeneous heating of the joining region of the two components to be joined together.

The device described in the publication has, in addition to the exclusive usability for glass components which have a cavity, further disadvantages. While the laser heats the irradiated portions of the glass components to be processed up to 1,200 to 1,500 ° C, part of this heat is radiated from the glass components again. In the interior of the glass components in which the Strahlungsleitvorrichtung is with the deflection mirror, therefore, there is a strong increase in temperature. Since the interior is completely surrounded by glass, this heat is difficult to dissipate. In addition, the measurement of the temperature of the glass component in the irradiated area is difficult, so that it is usually done from the outside. However, depending on the wall thickness of the hollow-cylindrical component, the measured temperature on the outside of the glass component may deviate significantly from the temperature on the inside. A precise control of the method due to the temperature of the glass components is thus difficult.

Another disadvantage is that the Strahlungsleitvorrichtung must be designed to be rotatable as a whole. As a result, relatively large masses must be set in rotation. In addition, the Strahlungsleitvorrichtung must be introduced into the interior of the glass components to be processed. As a result, the assembly process of the device shown in the cited document is time-consuming and error-prone.

In addition, the glass components to be joined together, in particular if they have a large diameter, must be set in rotation in order to prevent the heated soft glass components from collapsing inwards during the melting process.

From the DE 100 52 072 B4 For example, an apparatus and a method for processing a component made of quartz glass by means of a laser beam are known. In this case, a hollow cylindrical component is laser-worked on the inside. The laser beam is introduced from an end face into the hollow cylinder of the component, in which a displaceable deflecting mirror is arranged from the other side. The laser beam strikes the deflecting mirror, which besides the displaceability along the longitudinal direction is also rotatably mounted. The laser beam is thus deflected to the inside of the cylinder. Now, if the deflection mirror is set in rotation and simultaneously displaced along the longitudinal axis of the hollow cylinder, there is a spiral movement of the area which is irradiated by the laser. In this way, a surface finish, in particular a polishing of the inside of the hollow cylinder, possible.

From the US 2,648,166 a device is known with which two glass cylinders can be joined together. Again, the two glass cylinders are clamped horizontally and set in rotation to prevent the resulting centrifugal forces, a flow of the heated glass portion due to gravity. The heating takes place in the device shown via a gas burner, which is arranged in the interior of the glass cylinder, which are to be connected to each other.

The invention is therefore based on the object to develop a generic device and a method so that the Device can be fitted easily and quickly, the process is easily controllable and other disadvantages of the prior art are mitigated or completely eliminated.

The invention achieves the stated object by a device for processing at least one workpiece, which comprises a beam guiding device for guiding a laser beam irradiated into the device, which comprises a first deflecting mirror for deflecting the incident laser beam, which is mounted rotatably about a rotation axis that extends therethrough characterized in that the Strahlleitvorrichtung comprises at least a first annular mirror, which is arranged such that a deflected from the first deflecting laser beam to the at least one first annular mirror and is reflected.

Preferably, the first annular mirror has a central axis and is designed and arranged such that it reflects the laser beam irradiated into the device in the direction of the central axis. When deflecting, the laser spot is distorted because the deflection takes place on a curved surface. However, especially with ring mirrors that are planar in cross-section, the distortion takes place only in the circumferential direction, while the laser sport is not distorted substantially in a direction perpendicular thereto. Since the spot rotates over the circumference of the workpiece, the heat input takes place almost independently of the shape of the spot in this direction.

If a workpiece which is to be processed is now introduced into the device, a laser beam is irradiated into the device. This is guided by the Strahlleitvorrichtung to the desired position. He first encounters the first deflecting mirror, which deflects the laser beam. In this case, the deflection mirror rotates, so that the direction in which the laser beam is deflected by the first deflection mirror, also rotates.

The thus deflected laser beam now impinges on an annular mirror, which is arranged so that during the rotation of the first deflecting mirror of the deflected by this laser beam always hits the mirror surface of the first annular mirror. From there it can then be reflected, for example, directly onto the part of the at least one workpiece to be heated. If the laser beam, after it has been deflected by the deflecting mirror, reflected by the annular mirror in the direction of the central axis, it is ensured that it impinges on a part of the outer surface of the workpiece to be machined.

Preferably, the device comprises at least one holding device for holding the at least one workpiece. This is particularly advantageous for thin tubes or workpieces that can not be simply stacked, for example.

The device is particularly suitable for joining two workpieces, of which at least one has an area to be joined, which may consist of a glass. When joining the two workpieces they are arranged together and the contact area of both workpieces is heated by the irradiated laser beam. In the present case, the incident laser beam impinges from the outside on the workpieces to be joined by the deflection at the deflection mirror and the reflection at the first ring mirror. It has proven to be particularly advantageous when the laser beam strikes perpendicular or almost perpendicular to the outer surface of the workpieces to be joined. In this way, it is particularly well possible to irradiate the area to be heated and to ensure particularly good heat transfer. This can be achieved, for example, by deflecting the laser beam irradiated into the device at the deflecting mirror by less than 90 ° and, upon impinging on the first annular mirror, being reflected so that it impinges perpendicularly on the surface of the workpieces to be joined.

However, it is also possible with such a device, for example, to cut a workpiece or to adjust its geometry, for example, the circumference, exactly. This is especially possible for inner surfaces of a hollow workpiece. In addition, the workpieces to be machined may also consist of materials other than glass, for example of metal such as steel or of ceramic material. Also workpieces made of different materials can be connected together. It is conceivable, for example, the joining of a metal ring with a glass cylinder. The device ensures a nearly homogeneous circumferential heating of the workpiece to be machined. The ideal speed depends on how quickly the material to be processed radiates the heat absorbed and cools down locally. If necessary, already one revolution per second is sufficient. However, the higher the speed, the more homogeneous the workpiece will be heated over its circumference.

Advantageously, however, a second annular mirror is provided, which is arranged so that a deflected by the first deflecting laser beam impinges on the second annular mirror and is reflected on the first annular mirror. This can ensure that the laser beam runs parallel between the two ring mirrors to the outer surface of the workpiece to be machined, whereby the device can be made compact. The ring mirrors can also have an example spherical or cross-section parabolic shape, if desired for focusing reasons.

In a preferred embodiment, the first annular mirror and / or the second annular mirror are displaceably mounted in the direction of a longitudinal axis of the device. Thus, the area which is heated by the impact of the laser beam on the workpiece can be set very accurately. In non-planar cross-section ring mirrors, however, a displacement of the first annular mirror is bound to conditions that are to be maintained in order to ensure an optimal impact of the laser beam on the surface of the at least one workpiece. With ring mirrors that are planar in cross-section, a large area can easily be realized in which the ring mirrors can be displaced.

The laser beam is preferably radiated into the device, for example parallel to the longitudinal axis of the device, and deflected at a deflection direction in a direction perpendicular thereto. Here also every other deflection angle is conceivable. The beam direction, in which the laser beam is deflected at the deflection mirror, thereby rotates, as well as the deflection mirror is rotatably mounted and rotates during operation of the device. If, for example, a cylindrical or hollow-cylindrical workpiece is located in the device, the laser beam, after being deflected by the deflection mirror, for example, runs perpendicular to an axis of symmetry of the cylindrical workpiece. Here he meets the second ring mirror and is deflected at this down. At a certain distance, it then hits the first ring mirror, which redirects it to the outer surface of the workpiece to be reshaped or heated.

In order not to disturb or hinder the circulating laser beam, the holding device is preferably designed to be arranged in an inner space of the workpiece, so that no contact of the holding device with an outer surface of the workpiece is necessary. Of course, this is only possible with workpieces that have an interior and, for example, are shaped like a hollow cylinder. In this way it can be ensured that the parallel to the outer surface extending laser beam is not disturbed by a holder of the workpiece, deflected or blocked. The holding device may in particular have a plurality of clamping elements, which are arranged for example concentrically on an axis. The clamping elements can be displaced outwards and can thus build on the inside of a hollow cylinder pressure, which ensures that the holding device or the clamping elements can not be moved relative to the hollow cylinder, but pinch in the interior of the hollow cylinder.

Alternatively, of course, a holding device is conceivable that engages an outer surface of the workpiece and holds it so. In this case, if necessary, parts of the holding device must be equipped with mirror arrangements or deflecting arrangements for the laser beam in order to prevent blocking or deflection of the laser beam by the holding device. The laser beam is then passed around the portions of the fixture.

Preferably, the holding device is designed such that the workpiece is non-rotating storable. In particular, if, for example, large cylindrical or hollow-cylindrical glass bodies are to be connected to one another, then they can be supported upright vertically or substantially vertically. As a result, the workpieces no longer have to be mounted in a rotating manner in order to counteract the influence of gravity on the heated and thus soft and easily moldable glass material. A bleed of the material, as described in a horizontal storage in the prior art, is thus excluded and does not have to be compensated by a rotation of the workpieces. In particular, for large and heavy workpieces on the one hand the handling is simplified because these workpieces now no longer need to be rotated, on the other hand, the device can be structurally smaller and more compact and ultimately produced more cost-effectively.

It has proven to be particularly advantageous if the first deflecting mirror is a semipermeable mirror. Preferably, a second deflection mirror is provided, which is arranged such that a portion of a laser beam not deflected by the first deflection mirror strikes the second deflection mirror. During operation of a device, this could, for example, achieve that part of the laser beam is deflected at the first deflecting mirror and fed to the at least one annular mirror. This part of the laser beam is directed to the outside or an outer surface of the workpiece to be heated. A second part of the laser beam is not redirected by the semitransparent deflection mirror. This meets at a certain distance on a second deflection mirror and is deflected by this. If, for example, a hollow cylindrical workpiece is located in the device, the second deflection mirror is advantageously located in the hollow space of this hollow cylindrical workpiece. This makes it possible to make the second part of the laser beam, which was not deflected by the first deflecting mirror, also strike a region of the inner surface of the hollow cylindrical workpiece. By a suitable choice of the distances, it is possible that the area of the outer surface and the area of the inner surface, in which strike the two portions of the laser beam, lie directly opposite each other, so that it can come across the wall thickness of the hollow cylindrical workpiece away to a nearly homogeneous heating. Especially with workpieces with a large wall thickness, this procedure and this embodiment of the device makes sense.

Also, the second deflection mirror is rotatably mounted about the rotation axis, so that also the portion of the inner surface of the workpiece, on which the second part of the laser beam impinges, rotates. This ensures that an almost homogeneous heating of the component to be heated is achieved even over the circumference of the inner surface.

Preferably, the first deflecting mirror and the second deflecting mirror are connected to each other via a shaft. This makes it possible to ensure a particularly simple constructive manner that the rotational speed of the two deflecting mirrors is identical. On this shaft, for example, the clamping elements of the holding device can be arranged, which can attack from the inside to the workpiece and hold it so. The clamping elements may be arranged for example on a common bearing element, which is located on the shaft. The shaft is rotatably configured in this case relative to the bearing element, so that the bearing element itself can remain at rest relative to the rest of the device and also relative to a workpiece to be machined, so do not have to rotate with the shaft. This can be achieved that it comes to a clamping action of the clamping elements from the inside of the workpiece and yet the shaft can rotate with the second deflecting mirror located thereon so that the portion of the laser beam not deflected by the first deflecting mirror has a peripheral portion of the inner surface of the workpiece irradiated.

In one embodiment of the present invention, the device comprises a temperature sensor, for example a pyrometer, for determining a surface temperature of the workpiece, and the device additionally comprises a laser for irradiating a laser beam into the beam guiding device and a control unit, which is designed and set up, for example, electrically or electronically, to regulate a laser power emitted by the laser. The fact that the laser beam impinges on a region of the outer surface of the workpiece, the measurement of the temperature in this area directly from the outside in a structurally very simple way possible. By comparing the measured temperature values with a previously predetermined temperature setpoint curve, the parked laser power of the laser beam which is radiated into the beam-guiding device can be regulated. A sensor can also be arranged as an alternative to the second deflecting mirror so that the beam portion not deflected by the first deflecting mirror strikes the sensor and can thus be used to monitor the process. Then it may be advantageous if the majority of the power of the laser beam, for example 90%, is deflected by the first deflection mirror.

In a preferred embodiment, a tilt angle of the first and / or second deflection mirror is adjustable. Thus, the angle is changed by which the laser beam is deflected at the respective mirror. Thus, the position can be changed, at which the laser beam impinges on the surface of the workpiece. The adjustment of the tilt angle can be done, for example, by a fine servomotor, possibly even continuously, so that the irradiated surface can be set very accurately. However, a change in the tilt angle leads to changes in the wide beam path. In that case, it may then no longer be ensured that the laser beam runs parallel to the outer surface of the at least one workpiece between the two annular mirrors or still impinges perpendicularly on the workpiece.

• a) Umlenken des Laserstrahls durch einen ersten um eine Rotationsachse rotierenden Umlenkspiegel und
• b) Umleiten des umgelenkten Laserstrahls durch wenigstens einen Ringspiegel, so dass der Laserstrahl auf einen Bereich einer äußeren Oberfläche des wenigstens einen Werkstücks trifft.

An inventive method for processing the at least one workpiece is characterized by the steps,

• a) deflecting the laser beam through a first about a rotation axis rotating deflection mirror and
• b) redirecting the deflected laser beam through at least one annular mirror so that the laser beam strikes a portion of an outer surface of the at least one workpiece.

In particular, the deflected laser beam can be diverted through two annular mirrors.

It has proven to be advantageous that only a part of the laser beam is deflected by the first deflection mirror. The remaining part is then preferably deflected by a second deflection mirror such that it strikes a region of the inner surface of the at least one workpiece. Alternatively, the remaining part can also be directed to a sensor which, for example, measures the laser power irradiated into the beam guiding device, or the power of the remaining part. This information can be used to monitor the process. Preferably, the first deflecting mirror and the second deflecting mirror rotate at the same speed and in the same direction. This can, as already stated, particularly easy to implement by both mirrors are connected to each other via a common shaft.

The method is advantageously a method for joining a first workpiece and a second workpiece, wherein the at least one first workpiece has an area to be joined, which may consist of a glass, and the laser beam strikes the area to be joined of the workpieces. Such joining methods can be used, for example, in the production of glass tube elements for solar power plants. In this case, two short glass tube elements are initially provided with one metal ring at an outer end, on which later further components can be arranged. Subsequently, these two glass elements are placed on one end of a long glass tube, which may be four meters long, for example. This can be done for example with a joining method described here. The advantage here is that due to the relatively small diameter of these tubes, which may be 125 mm, for example, even with horizontal clamping or holding the glass workpieces to be joined a rotation of the workpieces is not necessary, since the influence of gravity is not sufficient here, a deformation outside the tolerance ranges. Thanks to the very simple temperature monitoring on the outside of the glass tubes, the temperature can be measured very accurately, so that the process can be well controlled by balancing with a desired temperature and a corresponding control unit. In this way, there is a fast and energy-efficient connection of the various glass components. In addition, the fact that the laser beam impinges on the workpieces from the outside, no deflecting mirror, which is in particular rotatable, must be placed in the narrow interior of the workpiece. As a result, on the one hand reduces the placement times and on the other hand, the device structurally simple and less error-prone executable.

Alternatively, the method can also be used for connecting larger components, for example glass cylinders with a diameter of one meter.

These can be stored vertically due to their stability, so that even here a rotation that would be very difficult to handle, especially in these heavy and large elements is avoided. Therefore, it is advantageous if the at least one workpiece can be stored vertically. Of course, the workpieces can also be stored horizontally or in any other orientation. This may make special demands on the respective holding device.

According to the invention, a glass tube for solar tube collectors comprises at least two glass partial tubes which have been joined by one of the above-mentioned methods. Characterized a chemical change of the components is effectively prevented compared to a use, for example, a gas burner for heating the components to be joined. If the components to be joined are heated with a burner, for example a gas burner, it can not be reliably ruled out that unwanted constituents are also contained which adhere to the surfaces of the components to be heated and change chemically. This is reflected in material stresses and possibly lower breaking strength. However, if the glass tubes are joined by a method described herein, these disadvantages can be effectively prevented.

With reference to drawings, an embodiment of the present invention will be explained in more detail below. It shows

1 A device according to a first embodiment of the present invention in a schematic 3-D view,

2 - in the 1 shown device from a different perspective,

3 - the device off 1 and 2 in a schematic cross-sectional representation,

4 A device according to a second embodiment of the present invention in a schematic 3D view,

5 - the device off 4 from a different perspective and

6 - The device according to the 4 and 5 in a schematic sectional view.

The 1 and 2 show a device according to a first embodiment of the present invention in schematic 3D representations from different perspectives. A laser beam 2 is introduced from above into the device. He meets a first deflection mirror 6 , This is in the illustrated embodiment at a 45 ° angle to the direction of incidence of the laser beam 2 so that the laser beam 2 from the first deflecting mirror 6 is deflected by 90 °. The first deflecting mirror 6 is rotatably mounted about an axis of rotation, in the embodiment shown in the figures with the direction of incidence of the laser beam 2 coincides.

After the laser beam 2 from the first deflecting mirror 6 was deflected, he meets the second ring mirror 8th from which it is deflected downwards in the figures. The second ring mirror 8th is designed so that the deflection of the laser beam 2 again by 90 °.

Will now be the first deflection mirror 6 rotated, the reflected laser beam also runs 2 circular around. However, he always hits the second ring mirror 8th so that it is always reflected. He then meets in the embodiment shown on the first ring mirror 10 , and is distracted from there again.

In the 1 and 2 are schematically a first workpiece 12 and a second workpiece 14 represented, which may for example consist of glass and to be joined together in the embodiment shown. For this they are arranged together. The contact area in which the first workpiece 12 with the second workpiece 14 comes into contact now by the laser beam 2 , from the first ring mirror 10 was redirected, warmed up. Because of that, the first deflecting mirror 6 rotates, also the impact point, at which the laser beam rotates 2 on the connection area between the first piece of work 12 and the second workpiece 14 meets, and runs around the circumference of the workpieces 12 . 14 around. Due to the high speeds, there is a nearly homogeneous heating of the joining area.

When redirecting the laser beam 2 at the first ring mirror 10 and at the second ring mirror 8th there is a distortion of the laser spot. Both ring mirrors 8th . 10 have curved surfaces on which the laser is reflected. However, this is only in the circumferential direction of the ring mirror 8th . 10 the case. In a direction perpendicular to this direction no distortion takes place. Around the joining area of the first workpiece 12 and the second workpiece 14 To heat as homogeneously as possible, the first deflection mirror 6 rotated at a relatively high speed of, for example, 1000 revolutions per minute. The heating thus takes place almost independently of the actual shape of the spot of the irradiated laser beam 2 in the circumferential direction. The through the first ring mirror 10 and the second ring mirror 8th caused distortion of the laser beam 2 Consequently, there is no appreciable influence in this direction. The device is therefore particularly suitable for methods in which it depends on a homogeneous heating of the entire circumference of the workpiece to be machined.

3 shows the device already shown in a schematic sectional view. One recognizes the laser beam entering from above into the device 2 , the first deflecting mirror 6 is distracted. Subsequently, the laser beam first strikes the second ring mirror 8th and then on the first ring mirror 10 before moving to the joining area between the first workpiece 12 and the second workpiece 14 incident. One recognizes in 3 clearly that a change in the tilt angle of the first deflection mirror 6 a shift of the entire following beam path of the laser beam 2 entails. If a change in the tilt angle takes place only to a very small extent, thereby the position of the laser beam 2 on the workpieces to be joined 12 . 14 be set very precisely. If the tilt angle adjustment exceeds a critical value, the laser beam hits 2 after redirecting to the first deflection mirror 6 no longer on the second ring mirror 8th or afterwards on the first ring mirror 10 , so it does not cause heating of the first workpiece 12 or the second workpiece 14 comes. The area in which the laser beam is aimed at the workpieces to be joined 12 . 14 meets, to be shifted to a greater amount, it makes sense to the first ring mirror 10 displaceable form. It can then in particular in a direction parallel to the axis of symmetry of the workpieces shown 12 . 14 , in the 1 to 3 so move up or down.

The 4 and 5 show a device according to a second embodiment of the present invention in a schematic 3D view from different perspectives. One recognizes again the laser beam irradiated from above into the device 2 , the first deflecting mirror 6 is at least partially diverted. The proportion of the laser beam 2 , the first deflecting mirror 6 is redirected, as in the 1 to 3 shown, first on the second ring mirror 8th from which he is on the first ring mirror 10 is reflected.

Here too is a first workpiece 12 and a second workpiece 14 provided, which are to be joined together and are arranged one above the other.

The part of the laser beam 2 , the first deflecting mirror 6 was deflected, meets after striking the first ring mirror 10 on the joining area between the first workpiece 12 and the second workpiece 14 and warm it up like this. By rotating the first deflecting mirror 6 the impact point runs over the circumference of the two workpieces 12 . 14 and heats the peripheral area so nearly homogeneous.

Unlike in the 1 to 3 shown is the first deflecting mirror 6 in the 4 and 5 formed as a semi-transparent mirror, so that a partial beam 16 the first deflecting mirror 6 happens without being diverted by it. Both the first workpiece 12 as well as the second workpiece 14 are designed as hollow cylindrical workpieces. The partial beam 16 now runs from above into the workpieces 12 . 14 and meets there on a second deflection mirror 18 , This one is about a wave 20 with the first deflection mirror 6 connected and thus rotatable together with this. The partial beam 16 is from the second deflecting mirror 18 deflected and now hits from the inside to the joining area between the first workpiece 12 and the second workpiece 14 , This is an even more homogeneous heating, especially in the radial direction of the workpieces 12 . 14 guaranteed. Alternatively to a second deflection mirror 18 For example, at this point, a sensor could also be arranged which, for example, determines the laser power which impinges on it and which can be used to monitor, control and / or regulate the method. For this purpose, it may be useful if designed as a semipermeable mirror first deflecting mirror 6 only a small part, for example, 5% or 10% of the laser power striking him passes and diverts the vast majority remaining.

In the 4 and 5 is clearly recognizable that the first workpiece 12 and the second workpiece 14 Do not turn during the joining process. The second workpiece arranged in the figures below 14 can, for example, on a base plate 22 be arranged standing. Additionally or alternatively, a holding device 24 provided in 5 through the first ring mirror 10 is covered. This holding device 24 is in this particular application on the shaft 20 arranged on the both the first deflection mirror 6 as well as the second deflection mirror 18 are arranged, and which rotates during operation of the device. The holding device 24 However, it is arranged so that it is on the shaft 20 is slidably mounted, for example, so that the holding device 24 with the wave 20 does not rotate. The holding device 24 has three support elements in the embodiment shown in the figures 26 that are different from one the wave 20 surrounding ring 28 to the respective workpiece 12 . 14 extend. The ring 28 is sliding on the shaft 20 stored, so that the shaft 20 relative to the ring 28 can turn. The support elements 26 For example, hydraulically from the inside to the inner surface of the respective workpiece 12 . 14 be pressed. As long as the frictional force generated thereby is greater than that between the shaft 20 and the ring 28 prevailing frictional forces, the holding device 24 not with the wave 20 rotated. In this way it is ensured that the workpieces to be joined 12 . 14 Do not rotate relative to the location of the device and the rest of the construction of the device, so that here the handling of the system, especially for large and heavy workpieces, is significantly simplified and the system can be designed structurally smaller. The holding device 24 is designed so that the workpiece held by her 12 . 14 is non-rotatably storable, although the shaft 20 with the attached deflecting mirrors 6 . 18 relative to the workpieces 12 . 14 rotates.

6 shows the device from the 4 and 5 in a sectional view. It can be seen again that the incoming laser beam 2 by the first deflecting mirror designed as a semipermeable mirror 6 is split. The part of the laser beam 2 , which is deflected, meets the second ring mirror 8th , on the first ring mirror 10 and then to the joint between the first workpiece 12 and the second workpiece 14 , He is doing outside of the first workpiece 12 bypasses. The partial beam 16 , the first deflecting mirror 6 is not deflected, however, enters the interior of the workpiece 12 and meets there on the second deflection mirror 18 that's about the wave 20 with the first deflection mirror 6 is coupled. In 6 is only a holding device 24 indicated schematically, a ring 28 which slides on the shaft 20 is stored and via support elements 26 with the first workpiece 12 connected is. This ensures that the workpieces 12 . 14 relative to the rest of the structure, in particular to the base plate 22 dont move.

In all embodiments shown, a particularly simple constructional configuration is possible if deflecting the laser beam 2 at each mirror by exactly 90 degrees. Of course, other deflection angles are conceivable, which may be useful and advantageous depending on the structural design of the device and the workpieces to be machined and the respective machining process.

LIST OF REFERENCE NUMBERS

2

laser beam

6

first deflecting mirror

8th

second ring mirror

10

first ring mirror

12

first workpiece

14

second workpiece

16

partial beam

18

second deflection mirror

20

wave

22

baseplate

24

holder

26

support element

28

ring

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

• DE 102008022259 A1 [0003]
• DE 10052072 B4 [0008]
• US 2648166 [0009]

Claims (20)

Device for processing at least one workpiece ( 12 . 14 ) comprising a beam guiding device for guiding a laser beam irradiated into the device (US Pat. 2 ) comprising a first deflecting mirror ( 6 ) for deflecting the irradiated laser beam ( 2 ), which is mounted rotatably about a rotation axis, characterized in that the beam-guiding device has at least one first annular mirror ( 10 ) arranged in such a way that one of the first deflecting mirrors ( 6 ) deflected laser beam ( 2 ) on the at least one first annular mirror ( 10 ) and reflected. Device according to claim 1, characterized in that the first ring mirror ( 10 ) has a central axis and is designed and arranged such that it transmits the laser beam irradiated into the device ( 2 ) is reflected toward the central axis, Apparatus according to claim 1 or 2, characterized in that the device comprises at least one holding device ( 24 ) for holding the at least one workpiece ( 12 . 14 ). Device according to claim 1, 2 or 3, characterized in that the device comprises a second ring mirror ( 8th ) which is arranged so that one of the first deflection mirror ( 6 ) deflected laser beam ( 2 ) on the second ring mirror ( 8th ) and from there to the first ring mirror ( 10 ) is reflected. Device according to one of the preceding claims, characterized in that the first ring mirror ( 10 ) and / or the second ring mirror ( 8th ) is slidably mounted in the direction of a longitudinal axis of the device. Device according to one of the preceding claims, characterized in that the holding device ( 24 ) is designed to be in an interior of the workpiece ( 12 . 14 ), so that no contact of the holding device ( 24 ) with an outer surface of the workpiece ( 12 . 14 ) is necessary. Device according to one of the preceding claims, characterized in that the holding device ( 24 ) is formed such that the workpiece ( 12 . 14 ) is non-rotating storable. Device according to one of the preceding claims, characterized in that the first deflecting mirror ( 6 ) is a semipermeable mirror. Apparatus according to claim 8, characterized in that a second deflecting mirror ( 18 ) is provided, which is arranged such that one of the first deflecting mirror ( 6 ) undeflected portion of a laser beam ( 2 ) on the second deflection mirror ( 18 ) meets. Apparatus according to claim 8 or 9, characterized in that the second deflecting mirror ( 18 ) is rotatably mounted about the rotation axis. Apparatus according to claim 10, characterized in that the first deflecting mirror ( 6 ) and the second deflection mirror ( 18 ) over a wave ( 20 ) are interconnected. Device according to one of the preceding claims, characterized in that a temperature sensor for determining a surface temperature of the workpiece ( 12 . 14 ), a laser for irradiating a laser beam ( 2 ) are provided in the Strahlleitvorrichtung and a control unit which is adapted to regulate a laser power emitted by the laser. Method for processing at least one workpiece ( 12 . 14 ), in which at least one laser beam ( 2 ) on at least a portion of the workpiece to be machined ( 12 . 14 ), characterized by the steps of: a) redirecting the laser beam ( 2 ) by a rotating around a rotation axis first deflecting mirror ( 6 ), b) redirecting the deflected laser beam ( 2 ) by at least one annular mirror ( 10 ), so that the laser beam ( 2 ) to a region of the outer surface of the at least one workpiece ( 12 . 14 ) meets. Method according to claim 13, characterized in that the laser beam ( 2 ) by two annular mirrors ( 8th . 10 ) is deflected. A method according to claim 13 or 14, characterized in that only a part of the laser beam ( 2 ) by the first deflection mirror ( 6 ) is deflected. Method according to claim 15, characterized in that the part of the laser beam ( 2 ), which does not depend on the first deflecting mirror ( 6 ) is deflected by a second deflection mirror ( 18 ) is deflected in such a way that it reaches a region of the inner surface of the at least one workpiece ( 12 . 14 ) meets. Method according to claim 15 or 16, characterized in that the first deflecting mirror ( 6 ) and the second deflection mirror ( 18 ) rotate at the same speed and in the same direction. Method according to one of claims 13 to 17, characterized in that a first workpiece ( 12 ) and a second workpiece ( 14 ), wherein at least the first workpiece ( 12 ) has a region to be joined, which may consist of glass, and the laser beam ( 2 ) on the area of the workpieces to be joined ( 12 . 14 ) meets. Method according to one of claims 13 to 18, characterized in that the at least one workpiece ( 12 . 14 ) is stored vertically while it is being processed. Glass tube for solar tube collectors, comprising at least two glass sub-tubes, characterized in that the glass sub-tubes have been joined by a method according to one of claims 13 to 19.

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