DE102018114369A1 - SYSTEM AND METHOD FOR THE REPLACEMENT OF OPTICAL COMPONENTS AND LASER MACHINING HEAD - Google Patents

Abstract

The invention relates to a system for exchanging optical components in a laser machining head, and to a laser machining head and a method for exchanging at least one optical component in a laser machining system.

Description

The invention relates to a system for exchanging optical components in a laser machining head, and to a laser machining head and a method for exchanging at least one optical component in a laser machining system.

Field of application and background of the invention

Laser processing heads are used in material processing to focus, shape or otherwise manipulate laser light according to the requirements resulting from the process control. Above all, machining heads for focusing laser light onto a workpiece or for deflection by scanning elements are known. In this case, optical components such as lenses, mirrors and protective glasses are held in a basic mechanical housing. In addition to these classic optical components, however, more complex beam shaping by free-form elements or diffractive optical elements is also used today.

The version of the optical components is typically carried out directly in the mechanical base housing or in a rotationally symmetrical single version and is usually fixed by screw rings. For applications with very high laser powers of several kilowatts (kW) or with particularly high requirements for thermal stability, there are solutions with passive or active cooling of the optical components. For this purpose, for example, the mechanical base housing or an optical recording of a cooling liquid to go through.

During operation, especially at high laser powers, mainly in the kilowatt range, by increasing contamination, for example by entering into the processing head process gases, the optical components to permanent or even fatal damage to these optical components and thus the entire processing head come. Therefore, in conventional machining heads, a regular change of the optical components is required.

For the exchange of so-called protective glasses solutions are known that allow a quick manual change. For example, the use of drawers is known. In this case, the optical component is inserted in a holder and optionally fixed and can be removed with this holder from the base housing. In this case, only very small demands are usually placed on the precision of the positioning, since the protective glasses used have no beam-shaping and / or focusing effect.

Similar solutions are conceivable for other optical elements. However, these are only expedient for optical components that do not require dedicated cooling and whose use only places low demands on the precision of the positioning. DE 10 2011 016 932 describes an optical cartridge that protects from contamination by Plangläser. As a result, additional optical components are introduced, which in turn can pollute.

For more complex systems, it may sometimes be necessary to replace entire modules with sometimes several optical elements. That's how it describes EP 2 302 433 changing an entire optical unit of a zoom system. The optical unit consists of several optical components and a guide system for linear adjustment of the positions of the optical elements. Although such a solution allows the change to restore the optical properties, but represents a massive intervention in the system, which also requires you to perform in a dust-free environment.

The known implementations therefore have the significant disadvantage that, in the case of a required service and / or maintenance on a machining head, a considerable effort is made to replace optical components. This is not feasible in particular with optical components with simultaneous possibility of cooling or movement of the components, for example by the use of a linear guide. An exchange at the place of use is not possible due to the massive intervention in the blasting systems while maintaining the required cleanliness (penetration of dust, vapors, etc.). Furthermore, today there is no monitoring of the optical components in combination with interchangeable interfaces for the detection of a required service.

It is therefore an object of the present invention to provide a system, a method and a laser machining head with which optical components of a laser machining head can be exchanged particularly easily. The system, method and machining head are intended to be particularly suitable for operation in the kilowatt range, where cooling of the optical components and / or the laser machining head is required to reduce the thermal stresses resulting from the use of Laser radiation at power in the kilowatt range revealed to stand up. In addition, the Justageaufwand after the change of optical components are reduced to a minimum.

Description of the invention:

The problem is solved by the features of the independent claims. Advantageous embodiments of the invention are described in the dependent claims. It is therefore provided in a first aspect of the invention, a system for exchanging at least one optical component in a laser machining head, wherein the at least one optical component is inserted into a holding device and the laser machining head comprises at least one receiving device, wherein the holding device in the receiving device is insertable and a connection between the holding device and the receiving device can be produced by means of an interface and the receiving device is formed coolable.

For the purposes of the invention, it is particularly preferred that the at least one optical component, which is present for example in a laser machining head and serves to influence a laser light beam, is gripped in a holder. It is particularly preferred that the at least one optical component can be arranged in the holder. It is known in the art that the optical components of an optical system must be replaced periodically. In this respect, the present invention provides a device with which this component change can be carried out particularly simply and quickly, wherein a complex adjustment can be omitted by the advantageous structural design of the system.

Preferably, the system is equipped with a high-precision, easy-to-release interface, with which the holder can be fastened particularly securely in the receiving device of the laser machining head. This can for example be done with fasteners, such as screws. It is preferred for the purposes of the invention that the receiving device comprises a cavity in the laser machining head. This cavity advantageously serves to receive the holding device, in which preferably the at least one optical component of the system is located.

The receiving device can be cooled, wherein the processing head may comprise means for cooling for this purpose. It is preferred for the purposes of the invention that these coolants are formed, for example, by cooling coils and / or cooling bores, which are arranged in spatial proximity to the receiving device in the machining head. For the purposes of the invention, for example, it may be preferred that a thermal discharge takes place to the rear side of the machining head or the receptacle. The term "rear side of the receptacle" in the sense of the invention preferably describes the back of the cavity, which preferably forms the receptacle. The term "front of the receptacle" preferably describes the side of the receptacle into which the holding device with the preferably inserted optical component is introduced, wherein the front and rear sides preferably form opposite side surfaces when the processing head is considered abstracted as a cuboid.

In a preferred embodiment of the invention, the interface is adapted to establish a thermal contact between the coolable receiving device and the holding device. This represents a particular advantage of the invention, because in particular a cooling of the optical components in the holding device is achieved. The cooling is preferably arranged with respect to the receiving device so that advantageously the components of the system are cooled particularly intense, which are exposed to the strongest thermal loads and / or most sensitive to thermal stresses. These components are preferably the optical components that are held and / or grasped by the holding device. It is particularly preferred for the purposes of the invention that the cooling of the receiving device by means of indirect cooling, for example, a condensation cooling takes place. The preferably conductive cooling can take place in particular via the interface with a water cooling of the receiving device. It is in particular the optical components in a beam path which are exposed to particularly high thermal loads. This applies in particular when laser light with high powers, for example in the kilowatt range, is to be transmitted or short and / or ultrashort laser pulses with pulse durations in the range of nanoseconds to femtoseconds. Laser light with short and / or ultrashort pulses are characterized in particular by high pulse energies and pulse peak powers.

It is preferred for the purposes of the invention that the holding device is preferably also referred to as a holder, the laser machining head preferably also as a processing head and the receiving device preferably as recording, wherein the corresponding term pairs are preferably used synonymously. An optical component in the sense of the invention may preferably be selected from a group comprising a filter, aperture, lens, polarizer, mirror, protective glass, collimator and / or the like.

In a preferred embodiment of the invention, the invention relates to a system for exchanging at least one optical component in a laser machining head, wherein the system comprises at least one holding device for holding at least one optical component and a receiving device for receiving the holding device, wherein a connection between the holding device and the receiving device can be produced by means of an interface.

In a preferred embodiment of the invention, an optical component system of a laser processing head is proposed comprising a holding device adapted to hold an optical component, the holding device comprising an interface releasably connected to a receiving device in the laser processing head and is mountable by means of a changing device in the laser machining head, wherein the changing device is adapted to protect the optical components and / or the laser machining head from contamination. It is particularly preferred for the purposes of the invention that the holder can be mounted with a changing device on a coolable recording. The changing device is within the meaning of the invention an optional part of the system and can preferably be considered as a tool that is used for mounting and / or disassembly of the holding device with respect to the receiving device. Thereby, the cost of assembly and / or disassembly can be advantageously reduced significantly. No additional tools required, whereby the replacement of the optical components can be much easier. The changing device allows in particular the protection of the optical components and the machining head from contamination during assembly and / or disassembly, since advantageously only a minimal intervention in the overall system is required.

It is preferred for the purposes of the invention that the system comprises at least one receiving device and at least one holding device. It is particularly preferred if the system or the laser machining head holds two receiving devices and two holding devices.

In a further aspect, the invention relates to a machining head comprising a system according to the present invention. It is particularly preferred that the laser processing head comprises a coolable receiving device, which is adapted to receive a holding device comprising at least one optical component, wherein the holding device is connectable to the receiving device by means of an interface. A particular advantage of such a machining head and the system is that the optical components can be replaced without contamination, without requiring the implementation of the component change in a clean room is required. It is preferred for the purposes of the invention that the advantages and technical effects described for the system also apply to the machining head with the system according to the present invention, and vice versa. Another advantage is that the design and / or arrangement of the system both cooling, and a particularly simple component change can take place, the experts had previously assumed that the provision of both functionalities, especially in connection with laser power in kilowatts Area, is associated with technical difficulties. In this respect, the provision of the system with holder and interface, which may be associated with a recording device, represents a departure from the prior art. In particular, the feature combination of easy interchangeability and coolability of the recording device, which advantageously also causes a cooling of the holder and the optical component is a surprising departure from and a significant improvement over the prior art. Another advantage of the invention is that the optical component can be preferably designed to be movable. The mobility of the optical component in conjunction with the coolability and the ease of replacement of the components represents a surprising functionality of the system, which had previously posed technical challenges to the art. The experts had previously assumed that a simple component change in both mobile and cooled systems is difficult to implement.

The system preferably comprises an interface, which is preferably adapted to connect the holder to the receiving device. In a preferred embodiment of the invention, the interface of the holding device is formed by a surface with centering pin and orientation pin. The surface may also be referred to as a plane surface within the meaning of the invention. The connection between the holding device and receptacle is produced, for example, by the fact that the interface of the holder is designed as a plane surface with centering hole and orientation pin and is screwed flat to the receptacle. Thereby, the optical component, which is held and / or captured by the holding device, advantageously protected in the changing device and introduced by means of this in the machining head and / or removed. It is preferred for the purposes of the invention that the optical component is arranged in the holding device and can be introduced and / or introduced into the receiving device with the aid of the changing device. Advantageously, within the machining head, a connection between Holding device and receiving device are produced by means of the interface of the holder.

In comparison to systems known from the prior art, the interface between the holding device and the receiving device of the present invention is particularly simple. In particular, the components of the system, in particular the optical components and the holding device, can be formed so precisely by a pre-adjustment that a renewed adjustment is no longer required after the component has been replaced. As a result, the usable service life of the optical system can be significantly extended and the power efficiency of the system can be significantly increased. In particular, the component replacement can be done with the simplest tools, so that improved cleanliness and better handling of the system can be ensured when changing components. In the embodiment of the system comprising a changing device, the use of additional tools can advantageously be completely avoided.

A further advantage of the invention is that the design of the system and the arrangement of its components achieves mechanical separation between the optical component and the attachment mechanism. This interaction of holding device and receiving device for the purpose of forming a connection is achieved in particular by the interface of the system.

The receiving device can advantageously be designed as a guide carriage of a drive system. For the purposes of the invention, a drive system preferably comprises a linear drive, wherein the linear drive may preferably comprise a rail system for guiding.

It is preferred for the purposes of the invention that the receiving device is part of the processing head, wherein the receiving device is preferably adapted to receive the unit of optical component and holder, wherein a stable connection between this unit and the receiving device are preferably prepared by means of the interface can. Another advantage of the invention is that the changing device is preferably adapted to protect in particular the optical component from dirt and / or mechanical damage.

In a preferred embodiment of the invention, the system is set up to ensure cooling of the receiving device. In other words, the receiving device comprises means for cooling. It is particularly preferred according to the invention that the receiving device for the holder designed such that a cooling of the receptacle is provided. In conventional systems, it is usually necessary to remove the entire cooling device if an optical component of the system is to be replaced. This is very laborious and usually requires a re-adjustment of the optical system. It is within the meaning of the present invention that the cooling device can remain as part of the receiving device in the machining head, especially when an optical component of the system must be replaced.

In a preferred embodiment of the invention, the system is adapted to allow linear movement. The term "linear movement" in the sense of the invention preferably designates a movement of an object along an optical axis of the laser beam system. The movement of the optical component preferably proceeds substantially parallel to the optical axis. It may also be preferred for some applications that the system is additionally configured to perform a lateral movement. In this case, the optical component preferably moves in a plane that is substantially perpendicular to the optical axis of the laser beam system.

Due to the movable design of some components of the system, for example, the optical component, which is preferably arranged in the holding device, are reciprocated with respect to the optical axis. This is usually not possible with conventional systems known from the prior art, in conjunction with easy interchangeability and coolability of the optical component.

In a preferred embodiment of the invention, the receiving device comprises a sensor system for monitoring the quality of the optical components. For the purposes of the invention, the sensor system is used in particular to monitor the quality of the optical elements, wherein the quality of the optical components can be influenced, for example, by the degree of contamination or the quality of the underlying optical elements. The monitoring of the quality of the optical elements can be in particular by a temperature measurement and / or a scattered light measurement, without being limited thereto. It is preferred that the sensor system is part of the receiving device. It is preferred that the sensor may remain in the machining head when an optical component of the system is replaced. A particular advantage of the invention is that the system is set up so that the sensor system together with the preferably movable designed Recording device can be moved as a unit. This makes it possible for the sensor system to occupy a preferably identical position relative to the optics at all times t, as a result of which advantageously the measurement situation of the sensor system with respect to the optics preferably remains essentially unchanged. For example, the sensor system can be set up for measuring the temperature of the optical component. This means within the meaning of the invention preferred that the recording device is provided with a sensor for temperature monitoring, so that a universal interface for a variety of possible use scenarios is created. For the purposes of the invention, the sensors are preferably selected from a group comprising pyrosensory sensors, infrared sensors and / or scattered-light sensors, the sensors being in particular configured to detect infrared radiation.

In a further aspect, the invention relates to a method for exchanging at least one optical component in a laser processing system. Preferably, the laser processing system comprises or is formed by a laser processing head. In the context of the proposed method, it is particularly preferred that the laser machining head comprises at least one receiving device. The method is characterized in that the at least one optical component is inserted into a holding device. In a further step, the holding device is inserted into the receiving device and a connection between the holding device and the receiving device is made by means of an interface. In the context of the proposed method, it is particularly preferred that the receiving device can be cooled.

1. a) Einlegen der mindestens einen optischen Komponente in eine Haltevorrichtung
2. b) Einführen der Haltevorrichtung in die Aufnahmevorrichtung
3. c) Herstellung einer Verbindung zwischen der Haltevorrichtung und der Aufnahmevorrichtung mittels einer Schnittstelle.

In other words, the proposed method comprises the following steps:

1. a) inserting the at least one optical component in a holding device
2. b) inserting the holding device in the receiving device
3. c) establishing a connection between the holding device and the receiving device by means of an interface.

• 1 schematische Darstellung einer bevorzugten Ausführungsform des Systems
• 2 schematische Darstellung einer bevorzugten Ausführungsform des Systems
• 3 schematische Darstellung einzelner Komponenten einer bevorzugten Ausführungsform des Systems

The invention will be described in more detail with reference to the following figure; it shows:

• 1 schematic representation of a preferred embodiment of the system
• 2 schematic representation of a preferred embodiment of the system
• 3 schematic representation of individual components of a preferred embodiment of the system

1 shows a schematic representation of a preferred embodiment of the system ( 10 ). Shown is a processing head ( 14 ), as used in material processing, for example, to focus, shape or otherwise manipulate laser light. In gray tones, such a laser beam can be seen, which is essentially symmetrical about a beam axis (FIG. 24 ) of the optical system is arranged and of the optical elements ( 12 ) is changed in its shape. The processing head ( 14 ) in the in 1 represented example two recording devices ( 18 ), which are each equipped with a holding device ( 16 ). The recording device ( 18 ) can by means of an interface ( 22 ) with the holding device ( 16 ) get connected. This connection between cradle ( 18 ) and holding device ( 16 ) can be produced for example by a screw connection by the interface ( 22 ) is designed as a surface with centering hole and orientation pin, which with the receiving device ( 18 ) is screwed. The at least one optical component ( 12 ) is preferably in the holding device ( 16 ), which in turn are dependent on the changing device ( 20 ) can be recorded. For example, the attachment of the optical components ( 12 ) in the holding device ( 16 ) with a screw ring. It is preferred for the purposes of the invention that the unit formed of optical component ( 12 ) and holding device ( 16 ) with the receiving device ( 18 ) can be connected. In particular, the receiving device ( 18 ), wherein the means for cooling preferably in the processing head ( 14 ) are present. The system ( 10 ) may also include sensors, which preferably also in the receiving device ( 18 ) and configured to detect the temperature. These are preferably pyrosensory sensors, infrared sensors and / or scattered light sensors.

2 shows a schematic representation of a preferred embodiment of the system ( 10 ), in particular the replacement of the optical components ( 12 ) is clarified. According to the in 2 illustrated embodiment of the invention, the unit of optical component ( 12 ) and holding device ( 16 ), in particular substantially perpendicular to the beam axis ( 24 ) of the optical system. In this case, an assembly and / or disassembly of the unit, in particular by means of the changing device ( 20 ), which can preferably be considered as a tool and advantageously the at least one optical component ( 12 ) of the system ( 10 ) protects during assembly and / or disassembly. Is shown in 2 in particular a laser machining head ( 14 ) with two holding devices ( 16 ) and two recording devices ( 18 ), where in the upper part of the 2 the holding device ( 16 ) outside the laser Machining head ( 14 ) is present. In the lower area of the laser machining head ( 14 ) is the holding device ( 16 ) with the optical component ( 12 ) within the receiving device ( 18 ). It may also be preferred within the meaning of the invention, the rear portion of the cavity within the laser machining head ( 14 ) as a receiving device ( 18 ) to call. In this case, it is preferable that the holding device ( 16 ) by means of the interface ( 22 ) on the receiving device ( 18 ) is attached.

3 shows a schematic representation of individual components of a preferred embodiment of the system ( 10 ). In particular shows 3 a holder device ( 16 ) into which an optical component ( 12 ) can be inserted. This holding device ( 16 ) can be inserted into the receiving device ( 18 ) of a laser processing head ( 14 ), wherein an attachment of the holding device ( 16 ) within the receiving device ( 18 ) by means of the interface ( 22 ). This compound can be prepared for example by screwing the components. Replacing the optical components ( 12 ) can be achieved by using a changing device ( 20 ) essentials are facilitated. In particular, the use of external tools by the use of a changing device ( 20 ) are significantly reduced.

LIST OF REFERENCE NUMBERS

10

system

12

optical component

14

Laser processing head

16

holder device

18

cradle

20

changing device

22

interface

24

beam axis

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 102011016932 [0006]
• EP 2302433 [0007]

Claims (10)

System (10) for exchanging at least one optical component (12) in a laser machining head (14), characterized in that the at least one optical component (12) can be inserted into a holding device (16) and the laser machining head (14) at least one receiving device (18), wherein the holding device (16) is insertable into the receiving device and a connection between the holding device (16) and the receiving device (18) by means of an interface (22) can be produced and the receiving device (18) formed coolable is. System (10) after Claim 1 characterized in that the holding device (16) by means of a changing device (20) in the laser machining head (14) is mountable. System (10) after Claim 1 or 2 characterized in that the interface (22) is formed by a surface with centering pin and orientation pin. System (10) according to one or more of the preceding claims, characterized in that the receiving device (18) comprises a sensor for monitoring the quality of the optical components (12). System (10) according to one or more of the preceding claims, characterized in that the at least one optical component (12) is selected from a group comprising a filter, aperture, lens, polarizer, mirror, protective glass, collimator and / or the like. System (10) according to one or more of the preceding claims, characterized in that the receiving device (18) comprises a cavity in the laser machining head (14). System (10) according to one or more of the preceding claims, characterized in that the interface (22) is adapted to produce a thermal contact between coolable receiving device (18) and holding device (16). System (10) according to one or more of the preceding claims, characterized in that the laser machining head (14) comprises means for cooling the receiving device (18). Method for exchanging at least one optical component (12) in a laser processing system (10), characterized in that the laser processing system (10) comprises at least one receiving device (18) and the method comprises the following steps: a) inserting the at least one b) introducing the holding device (16) into the receiving device (18), c) establishing a connection between the holding device (16) and the receiving device (18) by means of an interface (22) , Laser processing head (14), characterized in that the laser processing head (14) comprises a coolable receiving device (18) which is adapted to receive a holding device (16) comprising at least one optical component (12), wherein the holding device (16) with the receiving device (18) by means of an interface (22) is connectable.

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