Laser processing machines with barrier-free accesses

Abstract

A laser processing machine arrangement includes a laser processing head for laser processing a workpiece, the workpiece comprising a processing zone from which laser radiation is emitted radially during operation of the laser processing head, a laser protection wall that surrounds the laser processing head and a danger region disposed around the laser processing head, the laser protection wall shielding the laser radiation that is emitted radially from the processing, and at least one opening in the laser protection wall, through which the danger region can be entered, wherein the laser protection wall and the at least one in the laser protection wall are arranged in such a manner that the at least one opening is completely shadowed by the laser protection wall or is completely shadowed with cooperation of the laser protection wall from the laser radiation during operation of the laser processing head.

Claims

1. A laser processing machine arrangement, comprising: a laser processing head for laser processing a workpiece, the workpiece comprising a processing zone from which laser radiation is emitted radially during operation of the laser processing head; a laser protection wall surrounding the laser processing head and a danger region disposed around the laser processing head, the laser protection wall shielding the laser radiation that is emitted radially from the processing zone during operation; and at least one opening in the laser protection wall, through which the danger region can be entered, wherein, the laser protection wall and the at least one opening in the laser protection wall are arranged in such a manner that the at least one opening is completely shadowed by the laser protection wall or is completely shadowed with cooperation of the laser protection wall from the laser radiation that is emitted radially from the processing zone during operation of the laser processing head.

2. The laser processing machine arrangement according to claim 1, wherein the at least one opening is constructed in a barrier-free manner.

3. The laser processing machine arrangement according to claim 1, wherein the at least one opening is disposed at floor level and extends at least 2.20 m in an upward direction.

4. The laser processing machine arrangement according to claim 1, wherein the at least one opening is located at least partially behind a shadowing portion of the laser protection wall, the at least one opening having a front edge and a rear edge with respect to the processing zone, the front edge and an adjacent portion of the laser protection wall shadowing the at least one opening along a length of the at least one opening that extends to the rear edge.

5. The laser processing machine arrangement according to claim 1, further including a monitoring system that registers entry of a control region comprising at least the danger region, the monitoring system constructed to automatically switch off the laser processing head when the monitoring system registers entry of the control region.

6. The laser processing machine arrangement according to claim 5, wherein the monitoring system is an optical monitoring system that comprises a light grille.

7. The laser processing machine arrangement according to claim 5, wherein the monitoring system monitors at least one boundary portion of the control region, the monitoring system permitting operation of the laser processing head only while the at least one boundary portion is identified as being free, and the laser processing head being automatically switched off when the at least one boundary portion is entered.

8. The laser processing machine arrangement according to claim 7, wherein a boundary portion is formed by a shadowed opening, such that a movable portion of the laser protection wall that at least in part defines the shadowed opening is able to be moved or pivoted between an open position and a closed position, wherein the open position enlarges an access to the danger region adjacent the at least one opening, and the closed position limits the access to the danger region to the at least one opening, wherein the monitoring system permits the boundary portion to be identified as being free only when the movable portion is in the closed position.

9. The laser processing machine arrangement according to claim 8, wherein the monitoring system comprises a transmission device and a receiving device, and one of the devices is arranged on the edge of the at least one opening on the movable portion of the laser protection wall, and the other of the devices is arranged on an opposing edge of the at least one opening on a non-movable portion of the laser protection wall.

10. The laser processing machine arrangement according to claim 5, further including a pre-warning system that monitors a pre-warning portion located upstream of a boundary portion and that transmits an optical and/or acoustic pre-warning signal when the pre-warning portion is entered, the pre-warning portion being spaced apart from the boundary portion by at least 40 cm.

11. The laser processing machine arrangement according to claim 5, further comprising at least one movable laser protection shield that can be configured in a deployed position to define a portion of the control region and a portion of the danger region that are completely shadowed from the laser radiation emitted radially from the processing zone during operation of the laser processing head, wherein with the laser protection shield in the deployed position, the monitoring system does not automatically switch off the laser processing head when the portion of the control region is entered, and the laser protection shield prevents entry into a remaining region of the control region.

12. The laser processing machine arrangement according to claim 1, wherein the laser protection wall further comprises at least one additional opening that can be blocked by a laser protection door and through which the danger region can be entered, the laser processing arrangement further comprising a protection system that automatically switches off the laser processing head when the laser protection door is opened.

13. The laser processing machine arrangement according to claim 1, wherein the laser radiation that is emitted radially from the processing zone during operation is partially shadowed by the workpiece, and/or by a workpiece supply system, and/or by the laser processing head, and/or by a casing of the laser processing head, such that the laser protection wall is partially constructed to be open in such shadowed spatial angular ranges.

14. The laser processing machine arrangement according to claim 1, wherein the laser processing head comprises a laser having a wavelength in the non-visible range.

15. The laser processing machine arrangement according to claim 14, wherein the wavelength of the laser is in the infrared range.

16. The laser processing machine arrangement according to claim 1, wherein the laser processing head comprises a laser whose laser beam is orientated in a downward vertical direction.

17. The laser processing machine arrangement according to claim 1, further comprising a punching head disposed in the danger region.

Description

DESCRIPTION OF DRAWINGS

(1) FIG. 1 shows a schematic top view of a laser processing machine arrangement, including two shadowed openings and two additional openings that are each closed with a curved sliding door.

(2) FIG. 2 shows a schematic top view of the laser processing machine arrangement of FIG. 1, with the curved sliding doors open.

(3) FIG. 3 shows a schematic perspective view of the laser processing machine arrangement of FIG. 2.

(4) FIG. 4 shows a schematic side view of the laser processing machine arrangement of FIG. 2, with an enlarged, detailed cut-out in the region of the laser processing head.

(5) FIG. 5 shows a schematic top view of a laser processing machine arrangement, including an automatic workpiece supply system, three shadowed openings, and a movable portion of a laser protection wall in a closed position.

(6) FIG. 6 shows a schematic top view of the laser processing machine arrangement of FIG. 5, with the movable portion in an open position.

(7) FIG. 7 shows a schematic perspective view of the laser processing machine arrangement of FIG. 6.

(8) FIG. 8 shows a schematic perspective view of the laser processing machine arrangement of FIG. 5, with a laser protection shield in a retracted position and with irradiated regions of the laser protection wall marked with shading.

(9) FIG. 9 shows a schematic perspective view of the laser processing machine arrangement of FIG. 8 with the laser protection shield in a deployed position.

DETAILED DESCRIPTION

(10) FIGS. 1 to 4 illustrate a first embodiment of a laser processing machine arrangement 1. As can be seen from FIG. 1 and FIG. 3, the arrangement 1 includes a laser processing machine 2 (e.g., a combined laser processing and punching machine for processing metal sheets). As shown in FIG. 3, the arrangement 1 has a laser processing head 3 and a punching head 4, which are disposed beneath a front hood 5 and arranged on a machine member 6.

(11) Workpieces that are arranged on a workpiece support 7 can be processed with the laser processing head 3, which includes a laser directed vertically downwards and the punch head 4. The workpiece support 7 can be moved in the direction of the arrow 8 forwards and backwards in order to orient a supported workpiece with respect to the processing heads 3, 4. It is also possible, using a transverse carrier 9, which is provided with workpiece receiving members (e.g., clamps), to move a gripped workpiece in the direction of the arrow 10 to the left and to the right in order to orient the workpiece with respect to the processing heads 3, 4.

(12) During laser processing of a workpiece, the laser beam strikes the workpiece in a region in a processing zone 11, which is indicated with a small checked circle in FIG. 1. From there, the laser radiation is propagated in all directions in a linear manner. This radial propagation of substantially scattered laser radiation can be harmful to people in the vicinity, in particular to their eyes. Therefore, the laser processing machine 2 is surrounded by a laser protection wall 12. The laser protection wall 12 is made of a material (e.g., sheet metal) which is non-permeable with respect to the laser radiation used and non-permeable in the region of viewing windows 14. The viewing windows 14 are formed of a special glass which is non-permeable with respect to the laser radiation used and are constructed in a central element 23 of the laser protection wall 12, upstream of a region where operating devices of the arrangement 1 are also typically arranged.

(13) As shown in FIG. 1, the laser protection wall 12 shields the environment around the processing zone 11 completely (e.g., over all azimuth angles φ from 0 to 360°). As shown in FIG. 4, a shielded vertical region (e.g., the shielded polar angle θ) is, however, limited in the embodiment shown substantially to the local radiation cone which is produced by a radiation delimitation or a gap between the workpiece and/or the workpiece support 7 and the laser processing head 3 and/or a tubular casing 13 of the laser processing head 3. As shown in FIG. 3, the laser protection wall 12 is constructed so as to be open primarily in a lower region close to the floor and further open in an upward direction.

(14) Again with reference to FIG. 1 and FIG. 3, there are provided in the laser protection wall 12 two floor-level openings 15, 16 at both sides of the central element 23. These openings 15, 16 are arranged (e.g., oriented) in the laser protection wall 12 in such a manner that no laser light emitted radially from the processing zone 11 can pass through them. In FIG. 1, beam paths 17, 18 which are nearest the openings 15, 16 are drawn with dotted lines starting from the processing zone 11. Front edges 19, 20 of the openings 15, 16, adjacent portions 21, 22 of the laser protection wall 12, and respective rear edges 62, 63 shadow the openings 15, 16. For the optical safety of persons outside of a danger region 24 surrounded by the laser protection wall 12, it is therefore not necessary to provide the openings 15, 16 with doors which are impermeable with respect to the laser radiation. The openings 15, 16 are therefore also configured so as to be permanently free from barriers (e.g., without doors), which improves the accessibility of the danger region 24, (e.g., to perform set-up operations).

(15) In order to prevent persons entering the danger region 24 through the shadowed openings 15, 16 from being endangered by scattered laser light, a monitoring system 29 is configured. The monitoring system 29 ensures that, when a control region 27, which, in the embodiment shown, is identical to the danger region 24 is entered, the laser beam of the laser processing head 3 is switched off, and preferably, any workpiece transport and/or punching operation is also interrupted. The openings 15, 16 constitute boundary portions 30, 31 of the control region 27, the entry to which is monitored.

(16) To this end, a light grille 28 is configured on the opening 16, an interruption of the control beam thereof signaling that the boundary portion 31 formed by the opening 16 has been entered and causing the laser to be switched off. Owing to the fact that the largest spacing AB in the light grille (e.g., raster) is 90 mm in this instance, even placing only one's head in the danger region 24 will be detected. In the same manner, the opening 15 is secured.

(17) In addition to entering the danger region 24 through the shadowed openings 15, 16, it is also possible to enter the danger region 24 through additional openings 25 which can be closed by laser protection doors 26. The laser protection doors 26 are constructed as sliding doors and are non-permeable with respect to the laser radiation used. The laser protection doors 26 are part of the laser protection wall 12 and are opened in this embodiment for substantially manual workpiece changes.

(18) The laser protection doors 26 have their own protection system 32, which senses an opening of the laser protection doors 26 by a resiliently loaded pressure switch, and which interrupts the workpiece processing operation when the laser protection door 26 is open, and in particular automatically switches off the laser beam on the laser processing head 3. Alternatively, the laser protection doors 26 are electronically unlocked only when the laser is switched off. Whilst FIG. 1 shows the laser protection doors 26 in the closed state, they are illustrated in the open state in FIGS. 2, 3, and 4. Accordingly, the laser processing head 3 can be operated only in the state shown in FIG. 1. It should be noted that the closed laser protection doors 26 overlap minimally with the central element 23.

(19) FIGS. 5 to 9 show another embodiment of a laser processing machine arrangement 1′ which is provided with an automatic workpiece supply system. The differences with respect to the previous embodiment are discussed below.

(20) As can be seen in particular in FIG. 5 and FIG. 7, the arrangement 1′ has a laser processing machine 2 similar to the laser processing machine 2 shown in FIG. 1 and FIG. 3, having a laser processing head 3 and a punching head 4 for processing sheet-like workpieces 33. Workpieces 33 are lifted from a store 36 for unprocessed workpieces (e.g., raw material) by a suction gripper carriage 34 and moved along a guiding path 35 (e.g., a portal) of the suction gripper carriage 34 through a passage 37 to the laser processing machine 2 and deposited. After the processing operation, the workpieces 33 in the region of the laser processing machine 2 are again lifted using the suction gripper carriage 34 and moved through the passage 37 to a store 38 for processed workpieces (e.g., good components).

(21) In order to protect people in the vicinity of the laser processing machine 2 from scattered laser radiation, there is again provided a laser protection wall 12 which is non-permeable with respect to the laser radiation used. The laser protection wall 12 has a large number of portions, in particular a central element 23 with viewing discs of glass which is non-permeable with respect to the laser radiation, a movable portion 39, a portion 40 which is close to the store 38, an impact wall 41, and a portion 45 which is close to the passage 37. The laser protection wall 12 surrounds a danger region 24 in which laser radiation which propagates radially from the processing zone 11 may occur and shields this laser radiation in an outward direction.

(22) The laser protection wall 12 has three openings 42, 43, 44 which are illustrated with dots in FIG. 5. The laser protection wall 12 and these openings 42, 43, 44 are arranged in such a manner that a portion of the laser protection wall 12 adjoining the openings 42, 43, 44 shadows the openings 42, 43, 44. The left portion 21 of the central element 23 in FIG. 5 thus shadows the opening 42 (for example, refer to the beam path 17 closest to the opening 42 with respect of the laser radiation emitted from the processing zone 11 during operation). The opening 43 is shadowed by the left end of the portion 40 close to the store 38 (for example, refer to the beam path 18 closest to the opening 43). The expanded opening 44 is shadowed by the inner portion of the portion 45 close to the passage 37 (for example, refer to the beam path 46 closest to the opening 44). The openings 42, 43, 44, as a result of their shadowed arrangement, also do not require any laser-impermeable cover during operation of the laser processing head 3, and are accordingly also constructed in a barrier-free manner without any door.

(23) In order to protect from the laser radiation persons entering the danger region 24 defined by the laser protection wall 12 and the openings 42, 43, 44 through the openings 42, 43, 44, an optical monitoring system 29 is provided (refer to the circles filled in a black color and rectangles in FIG. 5, which represent light grille or photoelectric barrier stations). The monitoring system 29 monitors a control region 27, which includes the entire danger region 24 and an additional region 47 in front of the openings 43, 44 at the outer limits thereof. Outer boundary portions 31a, 31b, 31c of the additional region 47 are illustrated in FIG. 5 with dot-dash lines. Furthermore, the opening 42 constitutes a boundary portion 30 of the control region 27. The monitoring system 29 also carries out monitoring along an inner side at a few portions of the laser protection wall 12.

(24) With the monitoring system 29, it is possible to identify when a person enters the control region 27. In particular, it is possible to monitor to this end an interruption of a control beam (e.g., a light grille) formed at the boundary portions 30, 31a, 31b, 31c. When a boundary portion 30, 31a, 31b, 31c is entered, the light grille is interrupted, and the laser in the laser processing head 3 is switched off. Preferably, all machine movements in the arrangement 1′ (e.g., movements of the suction gripper carriage 34) are then also stopped.

(25) There is also provided an additional opening 25 which is not shadowed and which is covered with a laser protection door 61 which is constructed as a telescope-like door. With a protection system 32, which includes a resiliently loaded pressure switch, it is ensured that, when the laser protection door 61 is opened, the laser processing head 3 and any machine movement are switched off.

(26) In order to make the laser processing machine 2 more efficient and in particular to reduce machine downtimes, a movable laser protection shield 48 may be provided in the region of the passage 37 (refer to FIG. 9 with the laser protection shield 48 in the deployed position and FIG. 8 with the laser protection shield 48 in the retracted position). When the laser protection shield 48 is deployed in an upward direction (lifting gate), it shadows a region 49 of the control region 27, which region is at the rear in FIG. 9 beyond the passage 37 and also includes a rear region 50 of the danger region 24 located beyond the passage 37. Entering the shadowed region 49 of the control region 27 or the shadowed region 50 of the danger region 24 is then possible without danger, even when the laser processing in the remaining control region 52 is active.

(27) In FIGS. 8 and 9, laser wall portions which are each irradiated with laser radiation are drawn with shading. When the laser protection shield 48 is retracted (as shown in FIG. 8), the laser radiation propagates as far as the impact shield 41. When the laser protection shield 48 is deployed, the laser radiation is blocked at the laser protection shield 48, and the region 49 is completely shadowed. In FIGS. 8 and 9, it can also clearly be seen that the laser protection wall 12 is not required at floor or ceiling level since, as a result of the workpiece 33, the workpiece support 7, the laser processing head, and/or a casing of the laser processing head, only a relatively small spatial angular range in the vertical direction (e.g., a small polar angular range) is irradiated.

(28) When a movable radiation shield 48 is used, the monitoring system 29 is configured in such a manner that the boundary portions 31a, 31b, 31c can be entered when the laser protection shield 48 is deployed, without the laser processing automatically being switched off. Then, in the shadowed region 49, it is possible to work in parallel with the main processing operation (during the laser processing operation in the remaining control region 52) In particular, workpieces 33 can be moved to the store 36 for unprocessed workpieces and removed from the store 38 for processed workpieces.

(29) As another specific feature of the arrangement 1′, the opening 42 adjoins the movable portion 39 (e.g., a pivoting gate) of the laser protection wall 12 (refer to FIG. 5, FIG. 6, and FIG. 7). When the movable portion 39 is pivoted into an open position, as illustrated in FIG. 6 and FIG. 7 along the shadowed opening 42, an access 53 to the danger region 24 is enlarged. However, switching off of the laser processing head 3 must then be ensured, since the increased access 53 for the most part is not shadowed from laser light which could be emitted from the processing zone 11 during operation.

(30) To this end, the monitoring system 29 has at the front edge 19 of the opening 42 a transmission device 55 and at the outer end 54 of the movable portion 39 a receiver device 57, the fixed transmission device 55 directing its control beam in a fixed direction in accordance with the arrow 58. When the receiving device 57 is not arranged in the arrow direction, the receiving device 57 cannot receive the control beam, which excludes a notification of the opening 42 or the boundary portion 30 as being free. However, if the receiving device 57 is arranged in the direction of the arrow, which is always the case when the movable portion 39 is in the closed position (as shown in FIG. 5), the opening 42 (as long as no one is in the opening 42) can be identified as being free, which enables the operation of the laser processing head 3. In the latter case, the receiving device 57 is arranged at the edge 51 of the shadowed opening 42 opposite the front edge 19. Accordingly, in the closed position of the movable portion 39 illustrated in FIG. 5, a laser processing operation can be carried out, but not in the open position of the movable portion 39, as shown in FIGS. 6 and 7.

(31) As can be seen in FIG. 5, there is further configured in front of the boundary portion 31a a pre-warning portion 60 which is monitored by an optical pre-warning system 59). The pre-warning portion 60 which is marked with a double-dotted and dashed line is in this instance approximately 40 cm in front of the boundary portion 31a (refer to spacing 56). If a person enters the pre-warning portion 60, a horn is activated and indicates to the person that another approach to the arrangement 1′ in the region of the automation, in particular entering the boundary portion 31a, will interrupt the workpiece processing operation. It is thereby possible to prevent unintentional entry of the control region 27 during the workpiece processing operation.

(32) It should be noted that the laser processing machine 2 of the arrangement 1′ in place of a punching head 4 may also have an additional laser processing head, for example, with an associated laser having a wavelength and/or power that are different from those of the laser in the processing head 3. The openings 42, 43, 44 are also arranged so as to be shadowed with respect to the additional processing zone 11a of this additional laser processing head.

(33) In some embodiments, a protection arrangement for a laser processing machine is proposed in which a laser protection wall, which is typically constructed in several parts, leaves passages which are shadowed internally with respect to a source of radially scattering laser light and through which it is possible to enter and leave the danger space internally without any barriers and without loss of time. Automatic release of the laser processing operation can be carried out when a machine photoelectric barrier or the like is confirmed. Owing to the barrier-free passages, there is no waiting time for opening or closing doors. In principle, an operator has both hands free for operating tasks and does not require them in particular for operating doors. There is no need to fear failure of machine actuators at entrances since no machine actuators are required. The placement of modules (e.g., individual components) of the laser protection wall is extremely flexible, and in particular, it is possible to produce almost any angle between individual modules just as long as the shadowing of the door-free passages or accesses is ensured. The shadowed door-free accesses or the danger region as a whole are monitored, preferably in a contact-free manner, and preferably optically (e.g., with photoelectric barriers or light grilles). Video monitoring, including 3D video monitoring, is also conceivable. Owing to the monitoring, provision is made for the laser to be switched off automatically when the danger region within the laser protection wall is entered.

LIST OF REFERENCE NUMERALS

(34) 1, 1′ Laser processing machine arrangement

(35) 2 Laser processing machine

(36) 3 Laser processing head

(37) 4 Punching head

(38) 5 Front cover

(39) 6 Machine body

(40) 7 Workpiece support

(41) 8 Arrow direction (forwards/backwards)

(42) 9 Transverse carrier

(43) 10 Arrow direction (left/right)

(44) 11 Processing zone

(45) 12 Laser protection wall

(46) 13 Casing

(47) 14 Viewing window

(48) 15, 16 Shadowed opening

(49) 17, 18 Beam path closest to opening

(50) 19, 20 Front edge

(51) 21, 22 Part-portion

(52) 23 Central element

(53) 24 Danger region

(54) 25 Additional opening

(55) 26 Laser protection door (sliding door)

(56) 27 Control region

(57) 28 Light grille

(58) 29 Monitoring system

(59) 30, 31 Boundary portion

(60) 31a-31c Boundary portion

(61) 32 Protection system

(62) 33 Workpiece

(63) 34 Suction gripper carriage

(64) 35 Guiding path

(65) 36 Store for unprocessed workpieces

(66) 37 Passage

(67) 38 Store for processed workpieces

(68) 39 Movable part-portion

(69) 40 Part-portion close to store

(70) 41 Impact wall

(71) 42, 43, 44 Shadowed opening

(72) 45 Part-portion close to passage

(73) 46 Beam path closest to opening

(74) 47 Additional region of the control region

(75) 48 Laser protection shield

(76) 49 Shadowed part-region of the control region

(77) 50 Shadowed part-region of the danger region

(78) 51 Opposing edge

(79) 52 Remaining control region

(80) 53 Enlarged access

(81) 54 Outer end of the movable part-portion

(82) 55 Transmission device

(83) 56 Spacing

(84) 57 Receiving device

(85) 58 Arrow (transmission direction of the control beam)

(86) 59 Pre-warning system

(87) 60 Pre-warning portion

(88) 61 Laser protection door (telescope-like door)

(89) 62, 63 Rear edge

(90) AB Spacing (light grille)

(91) φ Azimuth angle

(92) θ Polar angle

(93) A number of embodiments have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of these embodiments. Accordingly, other embodiments are within the scope of the following claims.