CN113385828A

CN113385828A - Method and device for laser machining and machine tool

Info

Publication number: CN113385828A
Application number: CN202010168529.XA
Authority: CN
Inventors: 孙思叡
Original assignee: Shanghai Nagoya Precision Tools Co ltd
Current assignee: Shanghai Nagoya Precision Tools Co ltd
Priority date: 2020-03-11
Filing date: 2020-03-11
Publication date: 2021-09-14

Abstract

A laser implementing machine processing method, the laser that the laser launcher launches into a section of cavity first, and then after launching from the cavity, receive by the light-emitting part, launch by the said light-emitting part finally, is used for carrying on the processing to the work piece; the laser is propagated along a straight line, and the intersection angle of the propagation path and a rotating shaft is 0-15 degrees. The device manufactured by applying the laser machining method provided by the invention is arranged on a multi-axis machine tool and is combined with three linear motion axes and a rotary motion axis for fixing a workpiece to form a space multi-axis laser machining scheme, so that the workpiece is machined by laser in a rotary mode, the positioning error of the laser in the machining process is reduced, and the precision of the laser machining is improved.

Description

Method and device for laser machining and machine tool

Technical Field

The present invention relates to a machining method, and more particularly, to a method for precisely machining a hard material using a laser as a main means, and an industrial precision machining of a blade.

Background

The laser is a high-precision instrument, and the generator is connected with a laser head through a hard optical path or an optical fiber. The hard optical path usually cannot be moved frequently, and the optical fiber can only move gently in a small space, so that the requirements of multi-axis (such as three-axis, four-axis, five-axis, six-axis and the like) precision machining on efficiency and precision cannot be met.

In order to improve the machining efficiency of the laser, a swing head structure is applied to multi-axis machining, and is suitable for multi-axis laser machining of XA + YZB. The cutting structure is directly connected with the laser emergent end, the laser emergent end swings along with the swing mechanism, and the laser emergent end is usually close to the axis of the rotating shaft so as to reduce the traction of the moving range of the laser emergent end on the optical fiber. The five-axis machining device has the characteristic of simple structure, can be realized by additionally arranging the laser emitting end and the cutting mechanism on a common lathe, and can meet the requirements of some simple five-axis machining. The laser cutting machine is limited by the specifications of a laser emergent end and a cutting mechanism, a laser focus is far away from a rotary axis of a B shaft, and a large rotary radius always exists, so that the positioning error is amplified, the laser cutting machine is difficult to be competent for laser precise five-axis machining with micron-scale precision requirements, and the laser cutting machine is mainly used for laser cutting, laser punching, laser welding and the like of pipes in reality.

Therefore, another rotary swing table structure is developed, is suitable for multi-axis laser processing of XYZ + AB, can keep the swing of the laser emitting end to reduce the pulling on the optical fiber, and the rotary shafts are all superposed on the processed workpiece. When the length ratio of the workpiece to be machined is proper (according to the prior art, when the length of the workpiece is not more than 300mm, the arc length error is not more than 6 mu m), higher precision can be obtained. And because the laser emitting end does not swing, the service life of related components (especially optical fibers) is remarkably prolonged, and the stability is high. Therefore, it is widely adopted as the only solution in precision five-axis machining. However, as the aspect ratio of the processed part increases (i.e. the length of the workpiece is greater than 300mm), the processing precision of the method is rapidly reduced, and the processing of the long-axis part cannot be implemented. Therefore, the application range of the laser in machining is limited.

Disclosure of Invention

The invention aims to provide a method for carrying out machining by laser, which is used for expanding the application range of the laser in machining and meeting the machining requirements of parts with various specifications.

Another object of the present invention is to provide a method for performing laser machining, which reduces the positioning error of the laser during machining and improves the precision of laser machining.

Still another object of the present invention is to provide a method for machining with laser, which implements the machining with laser in a revolving manner, and is beneficial to improving the machining precision of long-axis workpieces.

The invention also aims to provide a laser machining method, which is applied to multi-axis machining equipment (such as a five-axis machine tool), improves the precision of laser rotary machining, reduces the movement and rotation of a laser device, prevents optical fiber from being pulled, prevents equipment failure caused by bending/falling of the optical fiber, and is beneficial to laser machining of parts with various specifications and simultaneously improves the reliability and stability of the equipment.

A fifth object of the present invention is to provide a laser machining apparatus for machining a workpiece by a laser beam in a rotating manner, which can improve machining accuracy and meet the requirements for precision machining of various specifications of parts.

Generally, a laser is a light emitted by an atom when the atom is excited, and when an electron in the atom absorbs energy and then transits from a low energy level to a high energy level and then falls back from the high energy level to the low energy level, the released energy is emitted as a photon. The laser forms can be classified into a continuous laser and a pulse laser. The laser is classified into a hot laser and a cold laser according to the pulse width characteristics of the laser.

The laser emitter comprises: but are not limited to nanosecond, femtosecond or picosecond lasers, producing lasers such as: infrared, blue, green, violet, or extreme violet.

In machining, a workpiece is generally a material or a semi-finished product used for manufacturing a part or a component, and is a machining object in a machining process. Namely, after the workpiece is machined, a product meeting the machining or design requirements is obtained.

Precision machining refers to a machining technique in which the machining precision and surface quality are extremely high. Such as: in the process of machining the cutter, the size, the straightness, the profile degree, the surface roughness, the arc radius of the blade tip and the machining precision are all higher than micron-sized.

Shaft-like workpieces, i.e. having a length at least 3 times the diameter.

A machining apparatus (or machining center) includes a plurality of movement axes. I.e., X, Y and Z axes moving in a linear direction, and a, B, and C axes of revolution about X, Y and Z axes, respectively, in a right-hand cartesian coordinate system.

Machining equipment, such as: numerically controlled machine tools are usually loaded with various control software, and receive and send various commands in the form of codes to automatically process workpieces.

The laser emitted by a laser emitter is firstly emitted into a section of cavity channel, then is emitted from the cavity channel, then is received by a light-emitting component, and finally is emitted from the light-emitting component, so that the laser can be used for machining a workpiece. The laser is transmitted along a straight line at the outlet end of the cavity channel, the intersection angle of a transmission path and a rotating shaft is 0-15 degrees, and 0-2 degrees are preferentially selected, such as: 0 ° (i.e., parallel or coaxial), 1 °, and 2 °.

When the method is implemented, the rotating shaft is an A shaft, a B shaft or a C shaft, and the laser emitted by the light emitting component is distributed around the rotating shaft direction, so that the laser emitted by the light emitting component is distributed around the rotating shaft direction, and the laser is implemented to be machined by rotating and positioning to a specified angle.

When the method is implemented, the laser emitter, the cavity channel and the light emergent part synchronously move along the linear axis, so that the laser distributed around the rotating shaft direction implements the machining of the workpiece according to the instruction.

In another embodiment of the laser machining method, laser emitted by the laser emitter is firstly emitted into a section of cavity, the laser is emitted into the cavity and then passes through the cavity, an intersection angle between a propagation path and a rotating shaft of the rotating mechanism is 0-15 degrees, the rotating mechanism drives the light emitting component to rotate, and the direction of a light beam emitted from the light emitting component correspondingly rotates.

In another embodiment of the laser machining method, in a right-hand rectangular coordinate system, the cavity is arranged on a shaft (e.g., B-shaft) rotating around a linear shaft (e.g., Y-shaft), the laser propagates along a straight line at the outlet end of the cavity, the intersection angle of the propagation path and the rotating shaft is 0-15 degrees, the light outlet part rotates around the rotating shaft, so that the emitted laser is distributed around the rotating direction of the rotating shaft, and the laser is machined in a rotating mode.

The light emergent part at least comprises one of a field lens, a galvanometer, a focusing lens, a beam expander and a reflector, and can be obtained from a market or an existing laser.

In another embodiment of the laser machining method, the laser emitter, the cavity and the light emergent part move synchronously along the Z axis in a right-hand rectangular coordinate system, so that the laser distributed around the B axis direction performs machining on the workpiece according to instructions.

In another embodiment of the laser machining method, before the laser is injected into the cavity, the laser is reflected or refracted to change the direction so as to maintain the position of the laser emitter without moving or swinging or pulling the optical fiber. Such as: the laser emitter is arranged on a Z axis, the emitted laser is reflected and then is changed in direction to be transmitted along a Y axis and is transmitted into the cavity channel, the laser is transmitted along a straight line at the outlet end of the cavity channel, the intersection angle of a transmission path and a rotating shaft is 0-15 degrees, the laser is received by the light emitting component and finally is emitted by the light emitting component to process the workpiece.

In order to implement the method of the invention, the laser emitted by the laser emitter is preferably selected to be transmitted along the linear direction from one end of the cavity to the other end of the cavity without deflection. A lumen with a through-going space may be used, such as: but are not limited to, straight tubular, conical and frustoconical bores or cavities and the like.

The method is applied to processing equipment with a plurality of moving axes (such as a three-axis machine tool, a four-axis machine tool, a five-axis machine tool and the like), can reduce the positioning error of laser in the processing, improves the precision of laser processing, is particularly suitable for the laser precision processing of long-axis workpieces, expands the application range of the laser in the processing, and is suitable for the processing requirements of parts with various specifications.

In order to apply the method of the invention to machining equipment, the invention also provides a device comprising

A hollow turntable comprising a rotating shaft;

the cavity channel is used for accommodating the propagation of laser and is provided with an axis which has an intersection angle of 0-15 degrees with the rotating shaft;

the laser transmitter emits laser into the cavity;

and the light emitting component rotates around the rotating shaft and receives the laser emitted by the cavity channel.

The invention provides a device, a turntable is as follows: but not limited to, an inner rotor turntable, an outer rotor turntable, a mechanical transmission turntable, a direct drive turntable and the like, and the inner part of the inner rotor turntable is hollow so as to be provided with cavity channels. The cavity channel arranged in the hollow rotary table is provided with a self-formed outer wall, or the inner wall of the hollow structure in the rotor is used as the outer wall of the cavity channel, and the cavity channel is the hollow structure in the rotary table at the moment, so that the space occupied by the device is reduced.

When the workpiece is processed, the laser emitter moves linearly or is fixed in position along with the turntable, and the emitted laser is reflected or refracted by the reversing component and then enters the cavity.

The device provided by the invention also comprises a reversing component, wherein laser enters the reversing component and then enters the cavity after being reflected or refracted. Thus, the position of the laser emitter is maintained, and the optical fiber is not moved or swung and is not pulled. Such as: the laser emitter is fixed on a Z axis, the emitted laser is reflected and then is changed in direction to be transmitted along a Y axis and is transmitted into the cavity channel, the laser is transmitted along a straight line at the outlet end of the cavity channel, the intersection angle of a transmission path and a rotating shaft is 0-10 degrees, the transmission path is received by the light emitting component, and finally the light emitting component emits the laser. In the process of machining a workpiece, in order to adapt to different machining requirements, the rotary table and the light emitting part synchronously reciprocate along the Z axis, and the position of the laser emitter is kept stable without swinging and moving, so that the optical fiber is prevented from being twisted and pulled.

The invention provides various devices which are arranged on a multi-axis machine tool, three linear motion axes, a rotary motion axis for fixing a workpiece and a laser beam rotary axis are combined to form a space five-axis laser machining scheme, so that the workpiece can be machined in a multi-axis mode, and products with complex and various structures can be manufactured. Such as: the machine tool is provided with at least three linear shafts, wherein one linear shaft is provided with the device (for example, the device is arranged on a plane determined by an X shaft and a Z shaft and moves linearly along the Z shaft), and the other linear shaft is provided with a rotary positioning mechanism for driving the workpiece to be machined to rotate and position (for example, the workpiece is arranged on the plane determined by the X shaft and the Y shaft), so that the machining precision of the workpiece is decoupled from the length of the workpiece, the precision of laser rotation machining is improved, and the laser machining of parts with various specifications is facilitated.

In another machine tool, a turntable of the device is arranged on a linear shaft, the device moves along the linear shaft, so that laser spots emitted by the light-emitting component move linearly, and when the light-emitting component rotates around the rotating shaft, the laser spots are distributed on a rotating surface to adapt to processing of various workpieces.

The technical scheme of the invention has the following beneficial effects:

according to the method provided by the invention, laser emitted by the laser emitter is firstly emitted into a section of cavity channel, so that the laser emitted by the light emitting component rotating around the revolving shaft is distributed around the revolving shaft direction, the workpiece is machined in a revolving mode by the laser, the positioning error caused by the revolving shaft error in the laser machining process is reduced, and the precision of the laser machining process is improved, such as: the five-axis machining error of the cutter is within 1 mu m.

According to the method provided by the invention, the laser emitted by the laser emitter is firstly emitted into a section of cavity channel, so that the laser emitted by the light emitting component of the winding rotating shaft is distributed in the direction of the winding rotating shaft, the application of the laser in the processing of long-shaft workpieces (such as more than 300mm) can be realized, the application range of the laser in the machining is expanded, and the method can be suitable for the processing requirements of parts with various specifications.

The method provided by the invention improves the precision of laser rotary processing, reduces the movement and rotation of a laser device, prevents optical fiber from being drawn, and prevents equipment failure caused by bending/falling of the optical fiber. The multi-axis laser machining device is applied to multi-axis machining equipment, and is beneficial to improving the reliability and stability of the equipment while laser machining is carried out on parts of various specifications.

The laser machining device manufactured by the method provided by the invention has a more compact structure, is beneficial to being applied to the existing machine tool or being convenient for reconstructing the existing machine tool, and is more beneficial to the arrangement and utilization of the space in the machine tool.

Compared with the existing equipment, the multi-axis processing equipment adopting the method of the invention has the advantage that the precision of the processed product is obviously improved. The emitted laser is distributed in the direction of the rotating shaft, so that the complex processing of parts with various specifications by the laser is realized, and various products can be processed in a one-key mode under the control of software.

Compared with the prior equipment, the device is applied to the multi-axis machine tool, the situation of the swinging or moving of the laser emitter is obviously reduced, the drawing situation of the light is reduced or stopped, and the service life is prolonged.

Drawings

FIG. 1 is a schematic view of one embodiment of an apparatus for use in the laser-implemented machining method of the present invention;

FIG. 2 is a schematic view of another embodiment of an apparatus for use in the laser-implemented machining method of the present invention.

Detailed Description

The technical scheme of the invention is described in detail in the following with reference to the accompanying drawings. Although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention as defined in the appended claims.

In the method for machining by using laser provided by the embodiment, laser emitted by a laser emitter is firstly emitted into a section of cavity channel, then is emitted from the cavity channel, is received by a light emitting component, and is finally emitted by the light emitting component for machining a workpiece; the laser is transmitted along a straight line at the outlet end of the cavity channel, and the intersection angle of the transmission path and a rotating shaft is 0-15 degrees. In a right-hand rectangular coordinate system, the rotating shaft is an A shaft, a B shaft or a C shaft, so that the laser emitted by the light emitting component is distributed around the rotating shaft direction, and the machining of the laser in a rotating mode is realized. In this embodiment, the cavity is disposed on the Y axis, the rotation axis is the B axis, and the light emitting element rotates around the B axis.

FIG. 1 is a schematic view of one embodiment of an apparatus for use in the laser-implemented machining method of the present invention. As shown in fig. 1, the apparatus of the present embodiment includes a laser emitter 100, a cavity lane 200, a light exit section 300, and a turntable 400.

The laser transmitter 100 is disposed at one end of the channel 200, and the laser 110 emitted from the laser transmitter 100 enters the channel 200. In this embodiment, the cavity 200 is a straight tube, and the laser 110 emitted from the laser emitter 100 is incident from the cavity 200 and then propagates in a linear direction without deflection, and exits to the other end. The emitted laser beam is received by the light emitting element 300, and finally, the laser beam 310 subjected to machining is emitted from the light emitting element 300.

In a right-hand rectangular coordinate system, the turntable 400 revolves around the Y-axis, the axis around which the revolution is made being the B-axis (not shown). The channel 200 has an axis (collinear with the laser 110 in the figure, not shown) that is coaxial with the B-axis. The light emitting member 300 rotates around the B axis, so that the emitted laser light is distributed around the B axis direction, and machining is performed by the laser light in a rotating manner. The turntable 400 is of a hollow structure, the cavity channel 200 is arranged in the turntable 400, namely, a section of the turntable 400 is located in a straight tube type hollow cavity, and the axis of the cavity is coaxial with the axis B and is also coaxial with the rotational symmetry axis of the turntable.

As the turntable 400 rotates, the channels 200 disposed therein are not displaced, so that the laser light 110 passing through the channels 200 always travels in a linear direction without being deflected and is always received by the light emitting part 300. The light emitting component 300 continuously rotates around the B shaft to form laser distributed around the rotation direction of the B shaft, the optical fiber does not need to be drawn, the distance between the laser focus and the rotation axis of the B shaft is shortened, the precision of positioning errors is improved, and the high-precision machining of workpieces is realized.

The device of the embodiment is applied to multi-axis machining equipment, so that the laser precision machining of long-axis workpieces can be realized, the application range of the laser in machining is expanded, and the device is suitable for the machining requirements of parts with various specifications.

FIG. 2 is a schematic view of another embodiment of an apparatus for use in the laser-implemented machining method of the present invention. Referring to fig. 1, as shown in fig. 2, the apparatus of the present embodiment is mounted on a support 600 disposed along the Z-axis of a machine tool, and the apparatus performs linear reciprocating motion along the Z-axis, and has a hollow turntable 420 rotating about the B-axis, in which a cavity 200 is provided. In this embodiment, the inner wall of the hollow structure in the rotor is used as the outer wall of the cavity, and the cavity 200 is a hollow structure cavity in the turntable. The laser emitter 100 is arranged on the support 600, the emitted laser 110 is reflected by the reversing component 500 to change the direction and then is emitted into the cavity channel 200, the laser 110 is transmitted along a straight line at the outlet end of the cavity channel 200, and the included angle between the laser 110 and the rotary B axis 410 is 0-15 degrees and is received by the light emitting component 300. The light emitting member 300 rotates about the revolution B axis 410 so that the laser light emitted therefrom is distributed about the revolution direction of the revolution axis. And then the three linear motion shafts on the machine tool and a rotary motion shaft for fixing the workpiece are combined to form a space five-axis laser machining scheme, so that the positioning error caused by the rotary shaft error in the laser machining process is reduced, the laser machining precision is improved, the workpiece is machined in a multi-axis mode, and products with complex and various structures are manufactured. Such as: the five-axis machining error of the cutter is within 1 mu m.

Claims

1. A laser implementing machine processing method is characterized in that laser emitted by a laser emitter is firstly emitted into a section of cavity channel, passes through the cavity channel, is received by a light emitting component, and is finally emitted by the light emitting component for implementing processing on a workpiece; the intersection angle between the path of the laser propagating in the cavity and the rotating shaft of the rotating mechanism is 0-15 degrees, the rotating mechanism drives the light-emitting component to rotate, and the direction of the light beam emitted from the light-emitting component correspondingly rotates.

2. The method of claim 1, wherein the path of propagation intersects the axis of rotation at an angle of 0 ° to 2 °.

3. The method according to claim 1, wherein in the right-hand rectangular coordinate system, the rotation axis is an a-axis, a B-axis or a C-axis, so that the laser emitted from the light emitting element is distributed around the rotation axis to realize the machining of the laser by rotating and positioning the laser to a specified angle.

4. The method according to claim 1, wherein the light emergent member comprises at least one of a field lens, a galvanometer, a focusing lens, a beam expander and a reflector.

5. A method according to claim 1 wherein said laser emitting device, said channels and said light exiting element are moved in synchronism along a linear axis so that laser light distributed about said axis of revolution effects machining of the workpiece on command.

6. The method of claim 1, wherein the laser light is further reflected or refracted to change direction before being injected into the channel during machining to maintain the position of the laser emitter without moving or wobbling and without pulling the fiber.

7. The method of claim 1, wherein said laser light is generated using a nanosecond, femtosecond or picosecond laser.

8. The method of claim 1, wherein the laser is selected from the group consisting of far infrared, blue light, green light, violet light, and extreme violet light.

9. A machine tool for machining a workpiece by a method according to any one of claims 1 to 8.

10. An apparatus for implementing the method of claim 1, comprising:

a hollow turntable comprising a rotating shaft;

the cavity channel is arranged in the hollow rotary table, is used for accommodating the propagation of laser and is provided with an axis with an intersection angle of 0-15 degrees with the rotary shaft;

the laser transmitter emits laser into the cavity;

11. The apparatus of claim 10, wherein said turntable is selected from the group consisting of an inner rotor turntable, an outer rotor turntable, a mechanical drive turntable, and a direct drive turntable, and is hollow to provide said channels.

12. The apparatus of claim 10 wherein said laser emitting device moves linearly with said turret.

13. The apparatus of claim 10, wherein the laser emitting device is fixed in position, and the emitted laser light is reflected or refracted by the deflecting member and then emitted into the channel.

14. A machine tool comprising the apparatus of claim 10.

15. The machine tool of claim 14, including

Three linear motion axes;

the first rotary motion shaft is used for enabling the workpiece to perform rotary motion;

a second axis of rotational movement for providing the device of claim 10;

the machining precision of the workpiece is decoupled from the length of the workpiece, and the shafts are combined to form a space five-axis laser machining scheme.