Patent Description:
Generally, a laser processing head for processing a workpiece using a laser beam is mounted at one surface of its housing, a so-called mounting surface, to a carrier of a laser processing system, which supports or moves the laser processing head during laser processing. Within the housing, the laser processing head includes an optical path for the laser beam in which a plurality of optical components are arranged, e.g. for focusing or collimating the laser beam. During processing of a workpiece, splashes of molten material and smoke are generated. The housing protects the optical components and other parts of the laser processing head against dirt particles, such as splashes, dust, dirt and smoke.

Should optical components get dirty, an access for servicing or changing the optical component is required. Generally, as shown in <FIG> and <FIG>, a laser processing head <NUM> includes a housing <NUM> with a plurality of horizontal modules 10a, 10b, 10c which include different optical components and are connected to each other in vertical direction. The interfaces between the modules 10a, 10b, 10c are visible and represent potential weak points of sealing. The laser processing head <NUM> is mounted on a carrier <NUM> at a mounting surface <NUM> of its housing <NUM>.

In <FIG>, horizontal access to the optical components is illustrated (removal direction indicated by the double arrows). Access openings for servicing the optical components, such as collimating or focusing optics, included in the horizontal modules 10a, 10b, 10c are provided either on a front surface, i.e. a surface opposite to the mounting surface <NUM>, or on a lateral surface, i.e. a surface adjacent to the mounting surface <NUM>. The access openings may be covered by corresponding access covers which are screwed to the housing. However, still a considerable amount of dirt particles can enter the housing via the access openings, causing undesired thermal effects and reducing a lifetime of optical components. Moreover, for changing the optical components, it is normally not possible to remove only the optical component, but a larger unit must be removed from the housing. In <FIG> and <FIG>, these units are indicated by dotted lines. For instance, as shown in <FIG>, when changing the collimating optics, the collimating optics 42a must be removed together with a collimating driving unit 42b.

In <FIG>, a vertical access to the optical components is illustrated. Here, the horizontal modules 10a, 10b, 10c, and 10d have to be disassembled in order to remove the respective optical components therefrom (removal direction indicated by the double arrows). In the configuration illustrated in <FIG>, some of the optical components may be removed from the housing in horizontal direction, others in vertical direction after disassembling the housing into the respective modules 10a, 10b, 10c, 10d. Thus, access to the optical components inside the laser processing head is typically provided at various sides of the housing, except for the mounting surface of the housing.

However, the interfaces of the modules 10a, 10b, 10c, 10d and the access openings or access covers are heavily soiled by dust, smoke, splashes and the like. Hence, before opening the housing, the interfaces and access openings must be thoroughly cleaned. Yet, a perfect cleaning seems to be impossible. Sometimes, due to the cleaning process, dirt particles are additionally introduced into the housing, e.g. when compressed air is directed to sealings of the interfaces or access openings. Thus, even when access covers or sealings are provided at the interfaces or access openings, the housing is not fully protected from introduction of dirt particles.

Moreover, since the access to the optical components is typically provided on exposed surfaces of the housing, the user often feels invited to directly open the housing in the dirty environment of the laser processing system. Also, it is not intuitive which optical components should be accessed by the user, and which optical components should only be accessed by an experienced service engineer. This may lead to unintentional opening of the laser processing head, with drastic consequences.

Further, due to the many interfaces between the modules and access openings or covers which are visible in the mounted state of the laser processing head, only few areas are available for customized design.

The concept of current laser processing heads is still based on the design of CO2 laser processing heads, where simple, front-side or lateral-side access to the optical components was uncritical and practical. However, laser processing heads using lasers with a wavelength in the range of <NUM> to <NUM> are very sensitive for soiled optical components, since this laser wavelength range corresponds to the range of sizes of typical dirt particles. Thus, due to this relation, the dirt particles absorb more laser power than in laser processing heads using CO2 laser having a wavelength of about <NUM>. Thus, in times of high-performance fiber lasers, this design of front/lateral-side access is no longer up to date. <CIT> presents system for exchanging optical components in a laser processing head. <CIT> presents a focusing head of a laser beam provided with a focusing lens for a machine for working metal and non-metal parts. <CIT> discloses a laser focusing head with cassette for lens. <CIT> provides a working head for a laser beam machine.

It is an object of the present disclosure to provide a laser processing system including a laser processing head with improved sealing against dirt particles to make sure that optical components remain clean and operational for as long as possible, while still allowing access to the optical components of the laser processing head.

It is another object of the present disclosure to provide a laser processing head with easy and safe access to the optical components for service and replacement.

It is still another object of the present disclosure to provide a laser processing system including a laser processing head ensuring that access to at least some of the optical components is performed by experienced staff.

It is still another object of the present disclosure to provide a laser processing system including a laser processing head with improved outer appearance.

One or more of these objects are solved by a laser processing system according to claim <NUM>. Features of preferred embodiments are subject of the dependent claims.

The laser processing head may be a laser cutting head and/or a laser welding head. If there is a plurality of first optical components, a plurality of access openings may be formed in the mounting surface. A plurality of access openings may be formed in the mounting surface for respectively providing access to at least one first optical component, i.e. for respectively inserting/removing at least one first optical component therethrough. Each first optical component may be removable or insertable through a respective access opening. A respective access opening may be provided for each first component, or more than one first optical component may be accessible through one access opening.

The invention is based on the idea that among the surfaces of the housing of the laser processing head, the mounting surface is least exposed to dirt particles, such as molten material, dust, dirt and smoke. Therefore, by providing the access opening on the mounting surface, an amount of dirt particles entering the housing via the access opening can be reduced. Thus, a sealed state of the housing can be improved, thereby extending a period of use of optical components included in the laser processing head.

The plurality of optical components may define an optical path of the laser processing head, i.e. a path along which a laser beam travels after entering the laser processing head. It is well understood that the first optical component is not necessarily the first optical component along the optical path in propagation direction of the laser beam, but can be any optical component among the optical components arranged within the housing. The optical path may be linear or straight. Alternatively, the optical path for the laser beam may be angled, e.g. by including a mirror for reflecting the laser beam. Each optical component may have an optical axis. The mounting surface may extend in a plane parallel to the optical path of the laser processing head at an entrance point of the laser processing head at which a laser beam can enter the housing and/or the laser processing head, and/or in a plane parallel to the optical path of the laser processing head at an exit point of the laser processing head at which a laser beam can exit the housing and/or the laser processing head. The mounting surface may also extend in a plane parallel to an optical axis of the first component and/or in a plane parallel to an optical axis of a focusing optics included in the optical components.

The housing may form an exterior of the laser processing head. The housing may include several parts or modules which together form the exterior of the laser processing head. The carrier may be a carrier for holding or positioning the laser processing head during laser processing, e.g. a carrier of a laser processing system. That is, e.g. for laser processing, the laser processing head may be mounted on the carrier in a processing position in which the mounting surface is at least partially covered by the carrier.

Further, an access cover may be provided for opening or closing the access opening or at least one of a plurality of the access openings. The access cover may be removably mounted to the housing or to the mounting surface, e.g. by means of screws or the like. The access cover may be part of an optical frame or of a cartridge comprising the first optical component accessible via the respective access opening. Also, in some embodiments, the carrier may be configured to at least partially or fully cover the access opening in the mounted state of the laser processing head. If a plurality of access openings is formed in the mounting surface for respectively providing access to at least one of the first optical components, the access cover may be configured to open or close (i.e. to cover) one or more of the access openings. There may be even one access cover for all access openings. In case that more than one first optical component is accessible through one access opening, said access opening may be opened or closed by more than one access cover. Generally, however, the access cover is not required, as the function of opening or closing the access opening can also be fulfilled by the carrier. In this case, it is preferred that a sealing is provided between the carrier and the mounting surface.

The first optical component may include at least one of: a focusing optics, a focusing lens, a collimating optics, a collimating lens, a protective window, a mirror and a beam shaping optics. The first optical component may be insertable/removable through the access opening in a direction perpendicular to the mounting surface and/or to its optical axis. The first optical component may be mounted on an optical frame or in a cartridge. The optical frame or the cartridge may be coupled or connected to an access cover for opening or closing the corresponding access opening. The cartridge may be a sealed unit including two protective windows with the first optical component inserted therebetween. Thus, the optical frame or cartridge with the first optical component mounted therein may be removable through the access opening. That is, the first optical component may be removed while remaining mounted on the optical frame or cartridge. The access cover may be connected to the first optical component, in particular to the optical frame or cartridge. By these means, the first optical component, or the optical frame or cartridge with the first optical component, can be removed from the laser processing head together with the access cover, thus simplifying the exchange of optical components. The first optical component may be provided in plurality. One or more of the plurality of first optical components may be arranged coaxially to each other, i.e. their respective optical axis may extend coaxially.

The laser processing head may further include a driving unit installed in the housing for moving the first optical component parallel and/or perpendicular to the optical axis of said first optical component. For instance, the first optical component may be a focusing or collimating optics connected to a driving unit for adjusting a position thereof within the housing. The driving unit may include a motor. The driving unit may be a manual driving unit or an automatically or remotely controllable driving unit. In one embodiment, when removing the first optical component through the access opening, the driving unit for moving said first optical component may be configured to remain installed in the housing. For instance, the driving unit for moving said first optical component may be fixedly installed in the housing.

The plurality of optical components may include at least one second optical component, e.g. a protective window. The housing may include a further opening formed in a housing surface other than the mounting surface for removing or inserting the second optical component. Said other housing surface may extend in parallel to the optical path of the laser processing head at an entrance point of the laser processing head at which a laser beam can enter the housing and/or the laser processing head, and/or in a plane parallel to the optical path of the laser processing head at an exit point of the laser processing head at which a laser beam can exit the housing and/or the laser processing head. Said other housing surface may also extend in a plane parallel to an optical axis of the first component and/or in a plane parallel to an optical axis of the second component and/or in a plane parallel to an optical axis of a focusing optics included in the optical components. Said other housing surface may be facing the mounting surface, i.e. may be opposite to the mounting surface, i.e. spaced apart from and/or extending in parallel to the mounting surface. Said other housing surface may be adjacent to the mounting surface and/or extending perpendicular to the mounting surface. For instance, the second optical component may be the last optical component of the laser processing head in propagation direction of the laser beam. In other words, the second optical component may be an optical component, such as a protective window, that is closest to a processing side of the processing head and/or to an exit point where the laser beam exits the housing and/or the laser processing head. The laser processing head may further include a nozzle, and the second optical component may be an optical component, such as a protective window, adjacent or closest to the nozzle. The second optical component may be an optical component closest to an entrance point at which a laser beam enters the housing and/or the laser processing head. The laser processing head may further include a fiber coupler for coupling a laser light guide fiber to the laser processing head, and the second optical component may be a protective window or an optical component adjacent or closest to the fiber coupler.

The mounting surface may include a grounding area for electrical grounding of the laser processing head. The mounting surface may include alignment means, such as alignment pins or holes, for aligning the laser processing head with respect to the carrier. The mounting surface may include fixing means, such as screws, screw holes or bolts, for fixing the laser processing head to the carrier. The mounting surface may include excavated material or an excavation for weight reduction. The mounting surface may include at least one seal surrounding at least one or all of the access openings, e.g. in order to seal between the mounting surface and at least one of the access cover, the recess cover and the mounting cover.

The mounting surface may include a recessed portion in which the at least one access opening is formed. A recess cover for opening or closing the recessed portion at least partially or fully may be removably mounted to the mounting surface. The mounting surface may include a first recessed portion in which the at least one access opening is formed. One or more of the access openings may be removably covered by an access cover. The first recessed portion may be formed in a second recessed portion of the mounting surface. That is, the mounting surface may include two steps, i.e. three different levels. The (first and/or second) recessed portion may extend in a plane parallel to a portion of the mounting surface outside of the recessed portion(s). The recess cover may be configured to open or close the second recessed portion and/or at least one or all of the access covers.

The laser processing head may include a mounting cover for covering the mounting surface. A seal may be provided on the mounting cover and/or on the mounting surface, i.e. between the mounting cover and the mounting surface, when the mounting cover covers the mounting surface. The mounting cover may be hingedly coupled to the mounting surface and may be configured to be mounted on the carrier. That is, the mounting cover may be rotatably or pivotably coupled to the mounting surface, e.g. by at least one hinge unit. A hinge axis or rotation axis of the hinge unit may extend parallel to the mounting surface and/or to the optical path of the laser processing head and/or to the optical axis of the first optical component. By this hinged arrangement, the laser processing head can be rotated with respect to the carrier to expose the mounting surface and the access opening formed therein. Thus, an exchange of the first optical component can be performed without removal of the laser processing head from the carrier. Optical fibers, electrical connections and the like do not have to be disassembled but may remain connected to the laser processing head. Further, this hinged arrangement can be used with a conventional carrier of a laser processing system, since the mounting cover may provide mounting means for mounting the laser processing head to the carrier, in addition to the at least one hinge unit rotatably coupling the mounting cover to the mounting surface.

The mounting cover may have an arbitrary shape. Preferably, however, the mounting cover may have a frame shape for reducing weight. The mounting cover may include fixing means, such as screws, screw holes or bolts, to mount the laser processing head on the carrier.

Optionally, the laser processing head, in particular the mounting surface and/or the mounting cover, may include locking means for locking the laser processing head on the carrier in a processing position in which the mounting surface is at least partially covered by the carrier. The locking means may include a screw, bolt, clamp or latch or the like.

The housing may include at least one housing surface facing the mounting surface, i.e. opposite to the mounting surface, and/or at least one housing surface adjacent to and/or extending perpendicular to the mounting surface, said housing surface forming a continuous or integral or monolithic surface. Here, a continuous surface may mean a surface without openings or interfaces. The housing surface may extend parallel to the mounting surface. Thus, sealing of the housing and its components can be improved. Further, a large area can be provided for other functions, such as for customizing an exterior of the laser processing head, e.g. using decorative adhesive foils, or mounting cables or external devices. Thus, the housing surface may include means for cable guiding and/or mounting means for mounting external devices, such as cameras for process monitoring or displays.

The housing may include at least one housing surface facing the mounting surface, i.e. opposite to the mounting surface. This housing surface may be denoted as front surface of the housing. Lateral surfaces may connect the mounting surface and the front surface. The lateral surfaces may extend in parallel to the optical path of the laser processing head. At least one of the lateral surfaces may be formed as continuous or integral or monolithic surface. The front surface may be shorter than the two lateral surfaces. A gap may be formed between the front surface and a bottom surface of the housing. The bottom surface of the housing may be a housing surface extending perpendicular to the optical path at the exit point of the housing. The gap may be sealed by a transparent material. A LED array may be disposed within the housing adjacent to the gap such that light is emitted by the LED array through the transparent material. By means of the LED array, an operation state of the laser processing head may be indicated, while allowing for an integral or smooth look of the front surface. The LED array may include a plurality of LEDs configured for emitting light of different colors or of the same color.

The laser processing head, in particular its optical components, may be configured for use with a fiber laser and/or for use with a laser beam having a wavelength in the wavelength range of <NUM> to <NUM> or for use with a laser beam having a wavelength of <NUM> or <NUM> or <NUM>, and/or for use with a laser power of at least <NUM> kW, at least <NUM> kW, at least <NUM> kW, at least <NUM> kW, at least <NUM> kW, at least <NUM> kW or at least <NUM> kW, or with a laser power up to <NUM> kW.

The laser processing system may include a laser source for providing the laser beam to the laser processing head, e.g. via a light guide fiber. The laser source may be a fiber laser and/or configured to produce a laser beam having a wavelength in the wavelength range of <NUM> to <NUM> or for use with a laser beam having a wavelength of <NUM> or <NUM> or <NUM>, and/or for use with a laser power of at least <NUM> kW, at least <NUM> kW, at least <NUM> kW, at least <NUM> kW, at least <NUM> kW, at least <NUM> kW or at least <NUM> kW, or with a laser power up to <NUM> kW.

The carrier may be configured to shield the access cover when the laser processing head is mounted on the carrier and/or in the processing position of the laser processing head. The carrier may block or cover the access cover at least partially. The carrier may be configured to hold or position the laser processing head during laser processing, e.g. with respect to a work piece. The carrier may be mounted on a rail system to move the laser processing head in one direction or in two or three orthogonal directions. In one example, the carrier may include or be a part of a manipulator for moving the laser processing head, such as a robot arm having <NUM> or more axis, e.g. <NUM> axes.

The laser processing system may include a laser source for generating a laser power of at least <NUM> kW or at least <NUM> kW and/or for generating a laser beam having a wavelength in the range of <NUM> to <NUM> or having a wavelength of <NUM> or <NUM> or <NUM>.

A sealing may be provided between the mounting surface and the carrier. The sealing may be arranged along a circumference or outer edge of the mounting surface. The sealing may surround at least the access opening for sealing the same, in particular in the processing position of the laser processing head.

The mounting surface of the laser processing head may be hingedly coupled to the carrier, e.g. by means of at least one hinge unit. Thus, the laser processing head may be rotatably coupled to the carrier. By these means, the mounting surface and the access opening formed therein which is normally covered or blocked by the carrier can be easily exposed. Optionally, the carrier and/or the laser processing head may include locking means for locking the laser processing head on the carrier in a processing position in which the mounting surface is at least partially covered by the carrier. The locking means may include a screw, bolt, clamp or latch or the like.

The carrier may include a carrier frame mounted to the mounting surface of the laser processing head, the carrier frame exposing the access opening. Hence, the access opening may be directly accessible through the carrier frame.

The carrier may include a fully automated changing device for automatically changing the at least one first optical component.

Throughout this disclosure, same elements are denoted with the same reference signs.

Generally, a laser processing head <NUM> is mounted to a carrier <NUM> of a laser processing system at a mounting surface <NUM> of a housing <NUM> of the laser processing head <NUM>. In the related art, the mounting surface <NUM> has almost no other functions besides this mounting function. Although in the figures and in the detailed description, it is referred to a laser processing head having a linear optical path for the laser beam, the disclosure is also applicable to a laser processing head having a bent or angled optical path for the laser beam, e.g. due to a mirror or a beam splitter. Likewise, although in the figures and in the detailed description, it is referred to a laser processing head having a fiber coupler, the laser processing head can also have other coupling means for coupling a laser beam into the laser processing head at the entrance point of the laser processing head.

According to the present disclosure, the inventors have noted that the mounting surface <NUM> is the surface of the housing <NUM> that is best protected against dirt since it is at least partially or even completely covered by the carrier in the mounted state, i.e. during processing. Thus, the mounting surface <NUM> is selected for providing access openings to the optical components of the laser processing head. By moving the access openings from other surfaces of the housing to the mounting surface <NUM>, the tightness of the housing <NUM> against dirt particles can be improved. Moreover, at least one of the other surfaces of the housing <NUM> besides the mounting surface <NUM> can be designed as integral surfaces, i.e. without gaps, interfaces or openings, thereby improving an outer appearance. In addition, this increases the confidence of a user in the tightness of the laser processing head against dirt particles. The other surfaces may also be used for other functions. For instance, means for cable routing, a camera for monitoring the laser processing or a display may be mounted at one or more of these other surfaces.

In <FIG>, a rear view of a laser processing head <NUM> according to the present disclosure is shown. That is, the mounting surface <NUM>, which may also be referred to as a rear surface of the housing <NUM>, is shown. The laser processing head <NUM> includes several optical components arranged in an optical path within the housing <NUM>. For instance, the optical components may include a first protective window <NUM>, a collimating optics <NUM>, a focusing optics <NUM>, and a second protective window <NUM>. The first protective window <NUM> may be the first optical element in the optical path of the laser processing head, i.e. along the laser beam propagation direction. That is, the first protective window <NUM> may be the optical component closest to a fiber coupler or entrance point <NUM> of the laser processing head. Similarly, the second protective window <NUM> may be the last optical element in the optical path of the laser processing head, i.e. along the laser beam propagation direction. That is, the second protective window <NUM> may be the optical component of the laser processing head that is closest to a nozzle <NUM> of the laser processing head or to an exit point of the laser processing head. Of course, the laser processing head <NUM> may include additional protective windows, which may be arranged between the first protective window <NUM> and the second protective window <NUM>. Also, the laser processing head <NUM> may include only one protective window, i.e. either window <NUM> or window <NUM>. Although the focusing optics <NUM> and the collimating optics <NUM> are respectively illustrated as a lens, the focusing optics <NUM> and the collimating optics <NUM> may respectively include a lens, a group of lenses, a lens module and the like. Optionally, a further optical component <NUM> may be provided which can be another protective window or a beam splitter or the like. One or more of the optical components may be mounted on an optical frame and/or in a cartridge. Here, the cartridge may include at least two protective windows disposed on either side of the respective optical component, such as the collimating optics <NUM> or the focusing optics <NUM>.

For at least some of these optical components of the laser processing head, an access opening <NUM> for servicing or replacing the respective optical component is provided on the mounting surface <NUM>. The access opening <NUM> may be covered by an access cover <NUM>. However, the access cover <NUM> is not mandatory. The access opening may be covered by the carrier <NUM> or by a recess cover <NUM> (described below) or a mounting cover <NUM> (described below). When removing the access cover <NUM> from the mounting surface <NUM>, the access opening <NUM> is exposed and the respective at least one optical component is accessible, e.g. for servicing or replacement. In the example illustrated in <FIG>, the focusing optics <NUM> and the optical component <NUM> can be accessed via the same access opening <NUM>. However, an individual access opening <NUM> may be provided for each of the optical components separately. Likewise, the access cover <NUM> may cover only one access opening <NUM> or several access openings <NUM>.

As shown in <FIG>, fixing means <NUM>, such as screw holes, screws or bolts, may be provided additionally on the mounting surface <NUM> in order to mount the laser processing head <NUM> to the carrier <NUM>. Also, alignment means (not shown), such as pin holes and/or pins, may be provided on the mounting surface <NUM> for accurately and reproducibly aligning the laser processing head <NUM> with respect to the carrier <NUM>. Further, the mounting surface <NUM> may include a grounding area for electrical grounding of the laser processing head <NUM>. In order to reduce weight, the mounting surface <NUM> may be excavated, e.g. by including one or more recessed portions as described below with respect to <FIG>.

<FIG> shows a front view of a laser processing head <NUM> according to an embodiment of the present invention. The front surface <NUM>, i.e. the housing surface opposite to or facing the mounting surface <NUM>, has an integral or uniform appearance. Alternatively or additionally, lateral surfaces <NUM> of the housing connecting the front surface <NUM> and the mounting surface <NUM> and extending parallel to the optical path of the laser processing head may have a uniform or integral appearance. The front surface <NUM> may extend less far towards a bottom surface <NUM> of the housing <NUM> than the lateral surfaces <NUM> in order to form a gap <NUM> between the bottom surface <NUM> and the front surface <NUM>. The gap <NUM> may be sealed by acrylic glass or another transparent material. Behind the gap, a LED array may be disposed in order to indicate an operating state of the laser processing head <NUM>.

In <FIG>, a rear view of a laser processing head <NUM> according to another embodiment is shown. Most of the parts are identical to those of the embodiment shown in <FIG>. Thus, a detailed description thereof is omitted. In the embodiment shown in <FIG>, the mounting surface <NUM> is recessed. In the example shown, the mounting surface <NUM> includes a first recessed portion <NUM> in which one or more of the access openings <NUM> are formed, and a second recessed portion <NUM> in which the first recessed portion <NUM> is formed. The recessed portions may be recessed towards an inside of the housing <NUM>. In other words, the mounting surface <NUM> may include three different levels or two steps. However, the second recessed portion <NUM> is not required, i.e. the mounting surface <NUM> may also include only the first recessed portion <NUM>, i.e. only one step. By recessing the mounting surface <NUM>, weight of the housing can be reduced. Alternatively or additionally, as shown in <FIG>, the first recessed portion <NUM> may serve as seat area for one or more access covers <NUM>. In this case, as shown in <FIG>, the first recessed portion <NUM> may be covered or filled or closed by the access covers <NUM>. That is, the access covers <NUM> may have the same width and/or the same thickness as the first recessed portion <NUM> in order to fill the first recessed portion <NUM> completely, or in order to achieve a stepless surface of the mounting surface <NUM> and the access covers <NUM> when the access covers <NUM> are closing the respective access openings <NUM>. In <FIG>, the second recessed portion <NUM> is covered or filled or closed by a recess cover <NUM>. Here, the recess cover <NUM> has the same width and the same thickness as the second recessed portion <NUM> in order to fill the second recessed portion <NUM> completely and to achieve a stepless surface of the mounting surface <NUM> and the recess cover <NUM> when the recess cover <NUM> is mounted. The stepless surface may improve the appearance.

In <FIG> and <FIG>, lateral views of the laser processing head <NUM> according to any one of the embodiments shown in <FIG> are shown. In <FIG>, the laser processing head <NUM> has been removed from the carrier <NUM>. The double-arrows indicate the direction along which replacement of the optical components may be performed. As one can see, the replacement is performed in horizontal direction via the access openings <NUM> on the mounting surface <NUM>, i.e. in a direction perpendicular to the optical axis of the optical components or perpendicular to the mounting surface <NUM>. The dotted lines indicate the units which are removed from the housing <NUM>. In particular, the collimating optics <NUM> may be removed from the housing, while a driving unit 42a for moving the collimating optics <NUM> along its optical axis (arrow) and/or perpendicular thereto (not shown) may stay in place. Likewise, the focusing optics <NUM> may be removed without removing a driving unit 43a for moving the focusing optics <NUM> along its optical axis and/or perpendicular thereto (not shown).

Most of the optical components do not need to be accessed during normal operation. By providing the access openings <NUM> for these optical components at the mounting surface <NUM> on the rear side of the laser processing head <NUM>, the access openings <NUM> and the optical components can be protected against dirt and allow clean servicing thereof. Here, clean access is more important than servicing time. In order to improve the tightness against dirt, a sealing <NUM> may be provided between the mounting surface <NUM> and the carrier <NUM>, as shown in <FIG>. Preferably, the sealing <NUM> surrounds all access openings <NUM> or access covers <NUM>. Alternatively, a plurality of sealings <NUM> may be provided respectively surrounding one of the access openings <NUM> on the mounting surface <NUM>. By providing the access openings <NUM> for the optical components on the mounting surface <NUM>, the access openings <NUM> are not visible during normal operation. Moreover, the access openings <NUM> are protected against unauthorized access by a normal user. Also, sealing(s) may be provided between the mounting surface <NUM> and the access cover(s) <NUM>.

The second protective window <NUM>, however, may not be accessible via the mounting surface <NUM>. The second protective window <NUM> is a wear part and has to be checked and replaced regularly during normal operation. Therefore, as shown in <FIG>, the second protective window <NUM> may be accessible via a further opening <NUM> on the housing surface <NUM> opposite to the mounting surface <NUM>, i.e. via the front surface of the housing <NUM>. By these means, the access can be easily performed by a user. Yet, the present invention is not limited to this, but the second protective window <NUM> may also be accessible via the mounting surface <NUM>. Although the first protective window <NUM> is shown to be accessible via the mounting surface <NUM> in <FIG> and <FIG>, it may also be accessible via the front surface <NUM> like the second protective window <NUM>. This is in particular useful, in case that the laser processing head includes the fiber coupler <NUM>.

According to further embodiments of the present disclosure, the accessibility of the mounting surface <NUM> is improved for experienced staff by rotatably connecting the laser processing head <NUM> with the carrier <NUM> using one or more hinge units. Preferably, the laser processing head <NUM> may be rotatable about at least <NUM>° with respect to the carrier <NUM>. The rotation axis may be vertical. In other words, the rotation axis may extend parallel to the optical path of the laser processing head, i.e. parallel to the mounting surface <NUM>. The laser processing head <NUM> may further include locking means for locking the laser processing head <NUM> in a processing position, i.e. for blocking any rotating movement about the hinge units. The blocking means may be a latch mechanism or the like.

In one embodiment, as shown in <FIG>, the laser processing head <NUM> is provided with a mounting cover <NUM> that is hinged to the mounting surface <NUM> of the housing <NUM> by at least one hinge unit <NUM>. The hinge unit <NUM> may allow a rotation of at least <NUM>°. The mounting cover <NUM> is mountable to a carrier <NUM> of a laser processing system by fixing means <NUM>, such as screws or bolts. Thus, the laser processing head <NUM> is rotatable with respect to the mounting cover <NUM>, or with respect to the carrier <NUM>, about a rotation axis of the hinge unit <NUM>.

In another embodiment, shown in <FIG>, at least one hinge unit <NUM> is provided on the mounting surface <NUM> to be hinged to the carrier <NUM>. Thus, the laser processing head <NUM> can be rotatably coupled to the carrier <NUM> directly at its mounting surface <NUM>. For fixing the laser processing head <NUM> in the processing position at the carrier <NUM>, locking means, such as screws and screw holes, a latch assembly, a snapping mechanism or the like, may be provided at the carrier <NUM> and/or at the laser processing head <NUM>. In <FIG>, screw holes <NUM> are exemplarily shown at the carrier <NUM> for fixing the laser processing head in the processing position at the carrier <NUM> by screws. The corresponding screw holes in the processing head <NUM> are not shown.

According to further embodiments of the present disclosure, the accessibility of the mounting surface <NUM> is improved by the carrier <NUM> including a carrier frame <NUM>. As shown in <FIG>, the carrier frame <NUM> has a frame shape with an opening in the center. The mounting surface <NUM> of the laser processing head <NUM> is mounted to the carrier frame <NUM> such that the access covers <NUM> are exposed through the carrier fame <NUM>. Preferably, the carrier frame <NUM> surrounds all access covers <NUM> on the mounting surface <NUM> of the laser processing head. A sealing <NUM> may be provided between the carrier frame <NUM> and the mounting surface <NUM>, as mentioned earlier. By these means, the access openings <NUM> can be used for service of the optical components, without dismounting the laser processing head <NUM> from the carrier <NUM> or rotating the laser processing head <NUM> with respect to the carrier <NUM>. This improves both easy access and mounting stability of the laser processing head on the carrier.

The carrier <NUM> or the carrier frame <NUM> may include an assistance device which is configured to assist in releasing or guiding removal of the optical components. Alternatively, the carrier <NUM> or the carrier frame <NUM> may include an automated changing device for changing the optical components. The changing device may include a driving unit or motor as well as replacement components for each optical component. This allows a remotely controlled and fully automated change of the optical components.

Claim 1:
A laser processing system, comprising: a laser processing head (<NUM>), and a carrier (<NUM>) to which the laser processing head (<NUM>) is mounted;
the laser processing head (<NUM>) comprising:
a housing (<NUM>) including a mounting surface (<NUM>) for mounting the laser processing head (<NUM>) on the carrier (<NUM>);
a plurality of optical components (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) arranged within the housing (<NUM>); and
an access opening (<NUM>) for removing or inserting at least one first optical component (<NUM>, <NUM>, <NUM>, <NUM>) among the optical components (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
characterized in that
the access opening (<NUM>) is formed in the mounting surface (<NUM>) of the housing (<NUM>), and
wherein in a mounted state of the laser processing head (<NUM>), the carrier (<NUM>) covers the access opening (<NUM>).