JP6558834B2 - Laser processing head - Google Patents

Description

  The present invention relates to a laser processing head that performs laser processing by changing an irradiation angle by biaxial control.

  In an articulated type three-dimensional laser processing head, a laser one-point head device has been proposed (see, for example, Patent Document 1 or Patent Document 2). This laser one-point head device has a condensing lens, an A axis as an elevation axis for changing the directivity of the laser, and a C axis as a swivel axis, and a point where these A axis and C axis intersect. The laser focal points are designed to coincide.

  For this reason, there is a feature that the laser focal position does not move even if the A axis and the C axis are operated. For example, when the angle of the cut surface changes during cutting, or as a countermeasure against laser return light, for example, the head By tilting about 5 °, there is an advantage that it can be handled without troublesome calculation and correction. Further, in the case of a normal laser head, the machining range may be narrowed by the operation of the A axis, but it is also advantageous that the machining range does not change in a single point orientation.

JP-A-2-179379 JP-A-3-151184

  On the other hand, these laser single-point heads have a plurality of reflecting mirrors inside, and it is very important to adjust the optical axis to adjust the laser beam directivity by finely adjusting the angle of the reflecting mirror when assembling the laser head. It was a troublesome work, but it was a very troublesome work. That is, since it is necessary to adjust the optical axes of a plurality of mirrors, adjusting the optical axes of the individual reflecting mirrors requires a large amount of work. The adjustment of the optical axis of one reflection mirror includes, for example, the adjustment of the optical axes of four front and rear reflection mirrors, so that the work amount is much more than four times. Furthermore, the difficulty of adjusting the optical axis increases as the distance between the reflecting mirrors increases.

  For this reason, the conventional laser single-point head has a complicated structure, so that it becomes a large structure and the distance between the mirrors inevitably tends to be long. That is, a conventional laser single-point head emits divergent light from an optical fiber cable, which is converted into parallel light by a collimating lens, mirror-transmitted by a reflection mirror, and condensed by a condensing lens. Since the path is refracted 4 to 6 times, at least two condenser lenses and four to six reflecting mirrors are necessary, and the number of parts is large and the structure is very complicated.

  In addition, in terms of performance, the laser power generally decreases to about 98% when the reflecting mirror is passed once. Therefore, 0.98 is the fourth power = 92% when passing four times, and 0.98 when passing six times. The sixth power = 89%, which is approximately 90%, and the reflecting mirror is wasted in terms of energy efficiency.

  In view of the above, an object of the present invention is to obtain a laser processing head that achieves high energy efficiency while reducing the number of condensing lenses and reflecting mirrors to be a simple structure.

The laser processing head according to the first aspect of the present invention is a laser processing head that performs laser processing by changing an irradiation angle with respect to a flat or three-dimensional workpiece by biaxial control of a first rotation axis and a second rotation axis. And
A head main body, a first rotary shaft housing that is rotatably supported by the head main body around a predetermined rotary shaft, and a first rotary shaft housing that is rotatably supported around a predetermined second rotary shaft. One-point laser processing comprising: a second rotating shaft housing that is provided; a laser irradiating means disposed at the tip of the second rotating shaft housing; and a laser light transmitting means for transmitting laser light to the laser irradiating means. In the head
As the laser light transmission means, an optical fiber cable connected to the second rotation shaft housing and transmitting laser light to the laser irradiation means in the second rotation shaft housing is provided .
The optical fiber cable is supported at a rear end portion of the head main body by a constant load spring having a constant restoring torque and not changing depending on a displacement amount .

  A laser processing head according to a second aspect of the invention is characterized in that the optical fiber cable according to the first aspect is connected to the second rotating shaft housing via a bearing.

  A laser processing head according to a third aspect of the invention is characterized in that the second rotating shaft according to the first or second aspect has a point that intersects the first rotating shaft.

  A laser processing head according to a fourth aspect of the invention is characterized in that the first rotation axis and the second rotation axis according to any one of the first to third aspects intersect at an angle of 45 °. To do.

  According to a fifth aspect of the present invention, there is provided the laser processing head according to the third aspect, wherein the laser irradiation means according to the third or fourth aspect focuses on a point where the second rotation axis and the first rotation axis intersect. An optical lens is provided.

  According to a sixth aspect of the present invention, in the laser processing head according to the sixth aspect, the laser irradiation means according to the fifth aspect reflects one laser beam from the optical fiber cable and transmits the reflected light to the condenser lens. Is further provided.

  The present invention has an effect that it is possible to obtain a laser processing head that achieves high energy efficiency while reducing the number of condensing lenses and reflection mirrors to be a simple structure.

  In other words, the conventional processing head has a large number of parts and a complicated structure. However, in the present invention, the laser beam transmitting means includes an optical fiber cable for transmitting laser light to the laser irradiation means. Since the laser beam is connected to the second rotating shaft housing and transmitted to the condensing lens in the housing, the number of parts is inevitably reduced, resulting in a simple structure.

  In addition, the use of an optical fiber cable can reduce the number of lenses and reflection mirrors in the head, can suppress the attenuation of laser light due to the passage of the lenses and reflection mirrors, and achieve high energy efficiency. it can.

It is explanatory drawing which shows the structure of one Example of the laser processing head of this invention. It is explanatory drawing which shows the structure of the state which rotated the 2nd rotating shaft (A axis | shaft) housing of the laser processing head of FIG. It is explanatory drawing which shows the structure of the state which rotated the 1st rotating shaft (C-axis) housing of the laser processing head of FIG.

  In the present invention, a laser processing head that performs laser processing by changing an irradiation angle by two-axis control of a first rotation axis (C axis) and a second rotation axis (A axis) with respect to a plane or a three-dimensional work, A head main body, a first rotary shaft housing that is rotatably supported by the head main body around a predetermined rotary shaft, and a first rotary shaft housing that is rotatably supported around a predetermined second rotary shaft. A laser processing head including a second rotary shaft housing, a laser irradiation unit disposed at a tip of the second rotary shaft housing, and a laser beam transmission unit that transmits a laser beam to the laser irradiation unit. .

  The laser processing head includes an optical fiber cable that is connected to the second rotary shaft housing and transmits laser light to the laser irradiation means in the second rotary shaft housing. The optical fiber cable is connected to the second rotary shaft housing. The laser beam is transmitted to the condensing lens in the housing by being connected. For this reason, it is possible to obtain a laser processing head that achieves high energy efficiency while reducing the use of the laser lens and the reflection mirror to make the structure simple.

  That is, in the present invention, in order to suppress the reflection of the mirror lens at the head body as much as possible, after passing through the first rotating shaft housing with the optical fiber cable, the second rotating shaft housing provided with the laser irradiation means is arranged. By connecting, the mirror lens which has been conventionally arranged in the first rotating housing can be omitted, and a simple structure can be obtained. Further, by omitting the mirror lens, the attenuation of the laser light is reduced, so that high energy efficiency can be achieved.

  Since the optical fiber cable of the present invention is connected to the second rotary shaft housing, the optical fiber cable passes through the first rotary shaft housing with the optical fiber cable. For this reason, the first rotating shaft housing preferably has a region having a radius of curvature of the optical fiber cable or more.

  The optical fiber cable of the present invention is preferably connected to the second rotary shaft housing via a bearing. As a result, the optical fiber cable is not twisted even when the first rotating shaft housing and the second rotating shaft housing are rotated, and there are no restrictions associated with the individual rotation during processing. One end of the optical fiber cable is connected to the second rotating shaft housing via a bearing, but the other end is preferably connected to the head body by a constant load spring that has a constant restoring torque and does not vary with the amount of displacement. It only has to be supported.

  In addition, as a bearing of an optical fiber cable and a 2nd rotating shaft housing, what is necessary is just a bearing which does not transmit one rotation of an optical fiber cable and a 2nd rotating shaft housing to the other, A slide bearing, a rolling bearing, a magnetic bearing Although fluid bearings and the like are employed, rolling bearings such as roller bearings and ball bearings are inexpensive and advantageous in terms of maintenance.

  As the laser irradiation means disposed at the tip of the second rotating shaft housing of the present invention, the laser light from the optical fiber cable is focused on the point where the first rotating shaft and the second rotating shaft intersect. Since the condensing lens is provided, it is arranged just before the laser irradiation means in the second rotating shaft housing. For this reason, the laser light is transmitted to the condensing lens of the laser irradiation means without making the laser light from the optical fiber cable into parallel light.

  With this condensing lens, if the point where the first rotation axis and the second rotation axis intersect is set as the laser focus, a one-point directing type can be obtained. As a result, a collimating lens for parallel light can be omitted, and a single-point laser processing head that achieves high energy efficiency while achieving a simple structure by further reducing the use of laser lenses and reflecting mirrors can be obtained. it can.

  More preferable laser irradiation means further includes one mirror means for reflecting the laser light from the optical fiber cable and transmitting it to the condenser lens. That is, one mirror unit that reflects the laser light from the optical fiber cable, and one condenser lens that focuses the laser reflected light of the mirror unit at a point where the first rotation axis and the second rotation axis intersect. Prepare.

  FIG. 1 is an explanatory view showing a configuration of an embodiment of a laser processing head according to the present invention. FIG. 2 is an explanatory diagram showing a configuration in which the second rotating shaft (A axis) housing of the laser processing head of FIG. 1 is rotated by 180 ° around the A axis. FIG. 3 is an explanatory view showing a configuration in a state where the first rotating shaft (C-axis) housing of the laser processing head of FIG. 2 is rotated by 180 ° around the C-axis.

  As shown in the figure, the laser processing head 10 of the present embodiment is roughly divided into a head main body 11 and a first main shaft 11 that is rotatably supported around the C axis 20 that is a predetermined first rotation axis. A C-axis housing 21 serving as a one-rotation shaft housing, and an A-axis housing 31 serving as a second rotation shaft housing supported by the C-axis housing 21 so as to be rotatable around an A-axis 30 that is a predetermined second rotation shaft. It consists of.

  The head main body 11 is substantially cylindrical in appearance, and is inserted so that the other end of the cylindrical shape of the C-axis housing 21 is loosely fitted from one end of the cylindrical body. A C-axis bearing 12, which is a ball bearing as an A-axis bearing, is attached to the joint portion with 21 and is held rotatably. An optical fiber cable 40 as laser beam transmission means is introduced into the head body 11 from the optical fiber cable guide 15 at the center of the other end of the head body 11.

  A constant load spring 16 that relaxes the weight of the optical fiber cable 40, such as “Conston spring (trade name)”, is disposed at the rear end of the head body 11. Even if the laser processing head 10 is installed in the vertical direction, the constant load spring 16 has an advantage of reducing the downward movement due to the weight of the optical fiber cable 40. In addition, when the A-axis housing 31 operates, the bending radius of the optical fiber cable 40 inside changes, so that the protruding length of the optical fiber cable 40 changes. In order to follow this, there is an advantage that the constant load spring 16 is provided so as to cancel out the own weight of the optical fiber cable 40 and to help the optical fiber cable 40 enter and exit.

  The optical fiber cable 40 introduced from the rear end portion is introduced in the longitudinal axis direction of the cylindrical body of the head body 11 and introduced into the C-axis housing 21 at the front end portion. The head main body 11 is roughly divided into left and right in the figure, and a slider 17 that guides the optical fiber cable 40 is extended in the longitudinal direction in the direction of the tip, and this slider 17 is the central wall of the head main body 11. It is fixed by a slider rotation stop pin 18.

  The portion of the C-axis housing 21 that is joined to the head main body 11 includes a cylindrical communication portion 26 that covers the slider 17 of the head main body 11 and communicates with the optical fiber cable 40 guided from the inside of the slider 17, and the communication portion 26. To an A-axis housing 31. The extended portion 27 is an expanded region that is larger than the radius of curvature of the optical fiber cable 40. A flexible pipe 41 through which the optical fiber cable 40 passes is arranged from the communication part 26 to the middle of the expansion part 27. The flexible tube 41 assists the bending so as not to be bent to a state smaller than the radius of curvature of the optical fiber cable 40.

  The head body 11 and the C-axis housing 21 are rotatably held on the C-axis 20 by the C-axis bearing 12. As shown in FIG. 3, a C-axis housing gear meshing with a C-axis gear 14 driven by a drive motor 13 around the C-axis attached to the side wall of the head main body 11 is provided at the periphery in the vicinity of the communication portion 26 of the C-axis housing 21. 25 is formed, and when the drive motor 13 is driven, the C-axis housing 21 is rotated.

  The A-axis housing 31 is joined to an inclined wall surface 28 that is inclined by 45 ° with respect to the C-axis 20 of the expanded portion of the C-axis housing 21. A joining end portion of the A-axis housing 31 to the C-axis housing 21 is joined by a rear end cylindrical portion 36 inclined by 45 ° with respect to the inclined wall surface 28 of the expansion portion 27. Continuing from the rear end cylindrical portion 36 of the A-axis housing 31, a tapered laser beam irradiation portion 37 inclined by 90 ° with respect to the rear end cylindrical portion 36 is formed.

  The C-axis housing 21 and the A-axis housing 31 are rotatably held on the C-axis 20 with an A-axis bearing 22 which is a ball bearing as an A-axis bearing. A disc-shaped A-axis housing gear 35 is formed at the end of the rear end edge abutting portion 36 of the A-axis housing 31. As shown in FIG. 2, the A-axis housing gear 35 meshed with the A-axis gear 24 that rotates around the drive shaft that penetrates the housing of the A-axis driving motor 23 that is attached to the inclined wall surface 28 of the C-axis housing 21. The A-axis housing 31 is rotated when the drive motor 23 is driven.

  As described above, since the A-axis needs to be inclined by 45 ° with respect to the connector of the optical fiber cable 40, the connector of the optical fiber cable 40 is arranged in a direction inclined by 45 degrees in the large-diameter A-axis bearing 22. When the A-axis housing 31 rotates around the A-axis, the bending radius of the optical fiber cable 40 in the head changes, so that the protruding direction of the optical fiber cable 40 changes. In order to follow this, a flexible pipe having a good slip was provided at the entrance of the optical fiber cable 40.

  The front end portion of the optical fiber cable 40 that connects the head body 11 and the C-axis housing 21 is introduced into the rear end cylindrical portion 36 of the A-axis housing 31. Specifically, a fiber fixing portion 43 is fixed to the front end portion of the optical fiber cable 40, and this is fixed to a fiber swivel shaft 44. The swivel shaft 44 and the rear end cylindrical portion 36 are rotated by a fiber bearing 42 as a bearing. Holds freely.

  As described above, when the C-axis housing 21 and the A-axis housing 31 are operated, the optical fiber cable 40 is twisted. To eliminate this, a ball bearing is provided in the coupling portion of the optical fiber cable 40. The fiber bearing 42 prevents the optical fiber cable 40 from being twisted even when the C-axis housing 21 and the A-axis housing 31 are rotated, and there are no restrictions associated with individual rotations during laser processing.

  Laser light from the tip of the optical fiber cable 40 is transmitted to a laser irradiation unit 50 as laser irradiation means. The laser irradiation unit 50 includes a reflection mirror 51 and a condenser lens 52. Reflected by the reflecting mirror 51 as the mirror means installed at the bent portion of the rear end edge abutting portion 36 of the A-axis housing 31 and the laser beam irradiation unit 37, and reflected by the condenser lens 52 of the laser beam irradiation unit 37 reflected. The laser beam is converged. The laser focus F on which the laser light is converged is set at the intersection of the C axis 20 and the A axis 30. As a result, the laser processing head 10 of this embodiment is a one-point pointing type laser processing head.

  In this embodiment, the optical fiber cable 40 is connected to the A-axis housing 31 through the head main body 11 and the C-axis housing 21 and transmitted to the reflection mirror 51 and the condenser lens 52 of the laser irradiation means. It may be connected directly to the A-axis housing from the outside.

  As described above, the laser processing head 10 of this embodiment has a simple structure in which the optical fiber cable that transmits laser light is brought close to the condenser lens to the extreme eye. That is, in the present embodiment, since it has a very simple configuration with one condensing lens 52 and one reflecting mirror 51, the number of parts is inevitably reduced, resulting in a simple structure.

  Since the number of conventional reflecting mirrors is 4 in this embodiment, the number of adjustment work for the lenses and mirrors is ¼ or less. Further, since the distance from the mirror through the divergent light source of the optical fiber cable 40 is shorter than the conventional one, the adjustment is easier. In addition, due to the reduction of the reflection mirror and the condenser lens, the energy efficiency can be expected to be about 98% in this embodiment, while the energy efficiency is about 90%. Energy efficiency can be improved.

10: Laser processing head,
11 ... head body,
12 ... C-axis bearing (C-axis bearing),
13 ... C-axis drive motor,
14 ... C-axis gear,
15 ... Optical fiber cable guide,
16 ... constant load spring,
17 ... slider,
18 ... Slider detent pin,
20 ... C axis (first rotation axis),
21 ... C-axis housing (first rotating shaft housing),
22 ... A-axis bearing (A-axis bearing),
23 ... A-axis drive motor,
24 ... A-axis gear,
25 ... C-axis housing gear,
26 ... communication part,
27 ... Expansion part,
28 ... inclined wall surface,
30 ... A axis (second rotation axis),
31 ... A-axis housing (second rotary shaft housing),
35 ... A-axis housing gear,
36 ... rear end cylindrical portion,
37 ... laser beam irradiation unit,
40: optical fiber cable (laser light transmission means),
41 ... Flexible pipe,
42 ... Fiber bearing (bearing),
43: Fiber fixing part,
44 ... Fiber swivel shaft,
50: Laser irradiation part,
51. Reflecting mirror (mirror means),
52 ... Condensing lens,
F: Focus,

Claims (6)

A laser processing head that performs laser processing by changing an irradiation angle by two-axis control of a first rotation axis and a second rotation axis with respect to a plane or a three-dimensional work;
A head main body, a first rotary shaft housing that is rotatably supported by the head main body around a predetermined rotary shaft, and a first rotary shaft housing that is rotatably supported around a predetermined second rotary shaft. One-point laser processing comprising: a second rotating shaft housing that is provided; a laser irradiating means disposed at the tip of the second rotating shaft housing; and a laser light transmitting means for transmitting laser light to the laser irradiating means. In the head
As the laser light transmission means, an optical fiber cable connected to the second rotation shaft housing and transmitting laser light to the laser irradiation means in the second rotation shaft housing is provided .
The one-point-oriented laser processing head , wherein the optical fiber cable is supported at a rear end portion of the head body by a constant load spring having a constant restoring torque and not changing depending on a displacement amount .   The one-point directional laser processing head according to claim 1, wherein the optical fiber cable is connected to the second rotating shaft housing via a bearing.   3. The one-point-oriented laser processing head according to claim 1, wherein the second rotation axis has a point that intersects the first rotation axis. 4.   The one-point directional laser processing head according to any one of claims 1 to 3, wherein the first rotation axis and the second rotation axis intersect at an angle of 45 °.   5. The one-point directional laser according to claim 3, wherein the laser irradiation unit includes a single condensing lens having a focal point at a point where the second rotation axis and the first rotation axis intersect. Processing head.   6. The one-point pointing type laser processing head according to claim 5, wherein the laser irradiation means further comprises one mirror means for reflecting the laser light from the optical fiber cable and transmitting it to the condenser lens. .

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