CN217370913U

CN217370913U - Device and machine tool for correcting path deviation when laser direction is changed

Info

Publication number: CN217370913U
Application number: CN202123218082.1U
Authority: CN
Inventors: 孙思叡
Original assignee: Shanghai Nagoya Precision Tools Co ltd
Current assignee: Shanghai Nagoya Precision Tools Co ltd
Priority date: 2021-12-20
Filing date: 2021-12-20
Publication date: 2022-09-06
Anticipated expiration: 2031-12-20

Abstract

A device for correcting path deviation when laser pointing direction is changed comprises a rotary table, an ultrafast laser and a diaphragm. The rotary table performs rotary motion and comprises a cavity, the cavity is used for accommodating a light path of laser, and the laser emitted by the ultrafast laser passes through the rotary table through the cavity. The laser projection relay part is arranged on the rotary table, rotates around the rotary axis of the rotary table along with the rotary table, receives laser from the cavity exit end, emits the laser after the light path direction of the laser is changed, and at least comprises a first reflector. The aperture receives the light beam reflected from the first mirror. Use the utility model provides a device eliminates factors such as revolving stage rotation, stress, vibration, elastic deformation or temperature and leads to the skew direction of predetermineeing of light beam propagation on multiaxis lathe for laser accords with the direction of work piece and predetermines, and the facula shape that acts on the work piece also remains stable, in order to satisfy precision finishing's needs.

Description

Device and machine tool for correcting path deviation when laser pointing direction changes

Technical Field

The present invention relates to a device for adjusting a laser beam path, and more particularly to a device for compensating for a deviation in propagation direction and/or position of a laser beam propagating in a rotation manner, and a machine tool using the same.

Background

At present, laser is widely applied to cutting, welding and marking processes of metal plates and profiles, and also applied to the technical fields of manufacturing cutting tools and the like by processing superhard materials. The most common solution is to perform the cutting or welding process of metal plates and profiles by laser means by a multi-axis machining center or a multi-joint robot, wherein a focused light beam converged and emitted by a laser emitter (i.e. a laser output component for performing the process, commonly known in the industry by the name of a cutting laser head or a welding laser head according to the function) is driven by a mechanical axis to move relative to a workpiece to be cut or welded so as to complete the required processing action, and the focusing (also called heightening) of the laser and the plane to be processed is realized by a focusing module integrated in the laser or the Z axis of the multi-axis machining center. The laser transmitter is generally directly connected to the light output terminal of the laser generator through a dedicated industrial interface (such as QBH, etc.), which is an important functional component for highly integrating external optical path functions such as collimation, beam expansion, focusing and the like. Through the direct connection of the modular laser transmitter and the light-emitting terminal of the laser generating device, the equipment assembly is simplified, the system reliability is improved, more importantly, the mechanical motion structure and the light path structure are simplified, the change of the angle in the emergent direction of the focused beam can be directly realized by controlling the rotation motion and the pitching motion of the laser transmitter, and further, the larger processing freedom degree is achieved. In addition, the space free optical path is shortened to the greatest extent through the highly integrated light-emitting terminal and the laser transmitter, the adverse effect of external disturbance on the pointing accuracy of the light beam is avoided as much as possible, and the processing accuracy is improved. Although the scheme can realize the free change of the laser focusing direction in a large range, the positioning error of a focusing light spot can be obviously amplified due to the fact that the radius of the laser rotating along with the rotary table is larger, and the technical scheme requires that the light-emitting terminal of the laser generating device can move randomly along with the laser emitter in a free space, so that the technical scheme can be used only by an optical fiber continuous laser or an optical fiber pulse laser light source in the microsecond or nanosecond level, wherein the optical fiber continuous laser or the optical fiber pulse laser light source is formed by connecting the laser emitter and the light-emitting terminal by an optical fiber with bendable and drawing characteristics, and the optical fiber ultrafast laser generating device and a semiconductor laser generating device which do not transmit light through the optical fiber, which cannot freely bend and draw the optical fiber, cannot be used.

In order to combine free change of laser focusing direction in a large range and rotation positioning error as small as possible, a device with an eccentric swing structure is applied to equipment of a multi-axis machining center, and is suitable for multi-axis laser machining with machining axes of XA and YZB. This is possible for a typical pulsed laser, but the ultrafast laser is subject to technical conditions, its fiber does not have sufficient mobility characteristics (it may allow too large bending radius, too short maximum total length of fiber), and it cannot be mounted on a swing mechanism, which makes it difficult to integrate the ultrafast laser for machining in a five-axis machining center. In order to solve the problem, a flight light path scheme (such as CN202020298469.9 and CN202020298514.0) is further provided, in which some light beams pass through the center of the turntable and are emitted by a reflector arranged at the center of the turntable, and in the series of schemes, the laser beams are adjusted to be coaxial with the rotating shaft of the turntable, so that the light beams are always incident on the same point on the reflector positioned on the rotating shaft line of the turntable in the same direction no matter how the light path part on the turntable rotates along with the turntable, and the included angle of the laser beams emitted from the turntable on the rotating central rotating shaft line of the turntable is always constant. However, when the laser beam is not correctly adjusted or the laser beam is no longer coaxial with the center of the turntable due to various stress, vibration, elastic deformation, temperature and other factors generated during the operation of the machining center, the rotation of the turntable may cause the laser beam emitted by the laser via the central reflector of the turntable to undergo angular deflection or/and positional deviation (hereinafter referred to as "deviation") along with the rotation, and further cause the laser spot finally acting on the workpiece to deviate, resulting in poor machining precision and failing to meet the requirement of precision machining.

On the other hand, changing the focusing direction of the light beam by replacing a mechanical axis with an optical device such as a galvanometer is also a common solution, the technical scheme generally has no special requirements on the light source of the laser, although there are technical improvement schemes such as a front focusing galvanometer and the like, the focusing light beam can be adjusted only within a limited angle generally, and the requirement of large-scale free change of the focusing direction of the laser in industrial application is difficult to meet; however, the focus is limited, in the vibrating mirror processing scheme, no matter the front focusing vibrating mirror or the rear focusing vibrating mirror, a focusing mirror (field lens) with a larger diameter and a longer focal length (i.e. a working distance) needs to be arranged in order to obtain a larger processing breadth, the larger diameter focusing mirror (field lens) is difficult to manufacture and high in cost, and meanwhile, the longer working distance can reduce the laser beam pointing accuracy and further reduce the processing and positioning accuracy of the whole processing system, so that the free laser processing with the vibrating mirror to realize the high-precision laser in a large range, a large angle is too expensive and difficult to implement in many cases.

On the other hand, changing the angle of the workpiece to be processed by using a multi-axis mechanical structure is the most important solution in laser precision processing, and the solution generally fixes the laser to be vertically emitted downwards and places the workpiece on a rotary swing table, and adjusts the direction of the laser acting on the workpiece by controlling the pitching motion, the rotating motion and other modes of the workpiece, namely, the laser focusing direction is changed. The method has the highest beam pointing precision without substantially changing the laser path, and can simultaneously combine the advantages of means such as the embedding of optical devices such as a galvanometer and the like, the shortening of the light path and the like to further expand the processing flexibility. Therefore, the proposal is most widely applied in the advanced precision processing field such as laser processing of superhard materials. However, the scheme is limited by the arrangement of a multi-axis mechanical structure, and has no universal applicability, and particularly when the scheme is used for processing long-axis parts, the length of the part is enlarged, the turning radius of the part is enlarged, and further, the turning positioning error is enlarged.

Therefore, in summary, although the technicians have developed numerous technical means for high-precision large-angle laser processing, how to combine a larger beam pointing freedom degree with a better beam pointing positioning precision in the current laser processing still remains to be solved.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a skew device of correction route when the laser is directional to change to in eliminating ultrafast laser light path gyration, should receive factors such as stress, vibration, elastic deformation and temperature and take place skew, in order to satisfy precision finishing's needs.

Another object of the utility model is to provide a when directional change of laser rectifies the skew device in route for when revolving stage rotation and drive laser change are directional, laser is to the directional coincidence of work piece predetermine and remain stable, in order to satisfy precision finishing's needs.

Another object of the utility model is to provide a device that path deviation was rectified when the laser is directional to be changed for when revolving stage rotation and drive laser change were directional, the facula shape that laser acted on the work piece remained stable, in order to satisfy precision finishing's needs.

Still another object of the utility model is to provide a device that path is skew is rectified when directional change of laser for the path is skew is rectified when directional change of laser, to implement the skew correction to laser, makes when the directional direction of laser changes 30 and above, and laser still accords with to the orientation of work piece and predetermines, and the facula shape that acts on the work piece also remains stable, in order to satisfy precision finishing's needs.

A fifth object of the present invention is to provide a multi-axis machining center, especially a multi-axis machine tool with a device for correcting the deviation of the laser path when the laser direction is changed, so as to meet the requirement of precision machining, improve the machining precision, effectively control the machining cost, and especially solve the problem that the machining precision is too low due to the too large turning radius of the long axis part.

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.

Ultrafast laser refers to a pulsed laser that outputs laser light with a pulse width of tens of nanoseconds or less, i.e., on the order of picoseconds or less. The ultrafast laser relates to core components including oscillator, stretcher, amplifier and compressor.

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 utility model discloses in, one section chamber way is penetrated earlier to the laser that ultrafast laser jetted out, from the chamber way back of penetrating again, reentrant laser throws relay unit, and laser throws and jets out laser behind the light path that relay unit changed laser again, jets out after receiving by light-emitting component at last for implement processing to the work piece. The laser propagates in the cavity channel and propagates along a straight line at the outlet end of the cavity channel, and the laser emitted from the light emitting component is focused in the range of the rotating shaft, namely a laser beam focusing spot falls in a cylindrical space with the rotating shaft as the center and the radius of 100 mm.

The utility model discloses in, the chamber says and sets up in the revolving stage, and it has the coaxial axis with the revolving axle of revolving stage. The laser is injected into the cavity and propagates forward along a straight line, which is preset to propagate forward along the direction of the rotary shaft of the turntable (including parallel or coaxial). The laser projection relay member is provided on the turntable and is driven to rotate by the turntable. The first mirror also rotates with the rotation of the turntable, so that the direction in which the laser light reflected by the first mirror is directed changes, for example: the laser beam is incident on the laser projection relay member until it is emitted, during which the laser beam is directed to rotate 30 DEG or more.

In order to meet the precision machining requirement, the laser beam is propagated forward along a straight line while the intersection angle with a rotation axis (e.g., rotation axis of the turntable) is kept at 0 ° to 5 °, preferably 0 °, such as: parallel or coaxial. Thus, the propagation path of the laser beam entering the laser projection relay member after the emission thereof is also preset.

The laser projection relay member makes at least 1 reflection of the laser light to change the laser beam direction.

The light emitting part includes at least one of a field lens, a galvanometer, a focusing lens, a beam expander and a reflector, which may be commercially available or may be obtained from an existing laser.

A diaphragm refers to a component that plays a role in limiting a light beam in an optical system. It may be the edge of the lens, the frame or a screen with holes arranged. Its effect is mainly to limit the beam or to limit the size of the field of view (imaging range). The diaphragm that restricts the light beam most in the optical system is called an aperture diaphragm, and the diaphragm that restricts the field of view (size) most is called a field diaphragm. In the laser field, diaphragms are typically used to pre-tune the optical path or as part of a spatial filter to shape the beam.

The laser light path before the incidence galvanometer has a set distance and a set included angle with the rotary axis of the rotary table, and when the actual distance between the laser light path of the incidence galvanometer and the rotary axis of the rotary table and the deviation between the actual included angle and the set distance and the set included angle are overlarge due to factors such as stress, vibration, elastic deformation, temperature, rotary error and the like, the rotary table can cause extra laser positioning error, namely position deviation.

Under actual conditions, due to factors such as stress, vibration, elastic deformation, temperature, rotation error and the like, under the condition that the laser penetrating through the rotary table does not keep the original included angle and distance (such as coaxiality) with the rotary axis of the rotary table any more when the rotary table rotates, the laser transmission deflects and deviates. When the deviated laser changes direction through the laser projection relay part, the deviation degree of the deviated laser from the preset laser propagation path is further enlarged.

The utility model discloses a when the device was implemented, the revolving axle was A axle, B axle or C axle, and the laser that makes light-emitting component to jet out distributes around (revolving stage) revolving axle direction, realizes that laser light path implements machining with rotary motion and location to appointed angle.

The utility model discloses a when the device was implemented, revolving stage and set up laser projection relay part and the light-emitting part on the revolving stage along sharp axle synchronous motion to make the laser that distributes around gyration axle direction follow sharp axle synchronous motion and implement the machine tooling of work piece according to the instruction.

The utility model discloses a device sets up the diaphragm on the route of laser propagation, specifically, sets up after laser is followed the chamber and says the outgoing, again on the one section propagation path before the light-emitting component of penetrating. In the path, the laser is reflected at least for 1 time, and before the laser enters the light emitting component, the laser is subject to the action of the diaphragm, so that the diaphragm blocks the deviated laser beam, and the laser beam which is not deviated can pass through and continue to propagate, thereby enabling the laser light speed to accord with the preset propagation path.

The utility model discloses a device can also compensate the laser light path before the incident mirror that shakes. And the compensated laser path before the incidence galvanometer has a second distance and a second included angle with the rotary axis of the rotary table, when the second distance is compared with the set distance, the difference is less than or equal to 1 mu m, and the difference is less than or equal to 0.05mrad when the second included angle is compared with the set included angle, the relative position of the compensated laser path of the incidence galvanometer and the rotary axis of the rotary table is maintained.

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.

In a specific embodiment, when the laser rotates with the turntable and the direction pointed by the laser changes, the laser with the changed propagation direction after reflection continues to propagate towards the diaphragm, so that the laser beam passing through the diaphragm continues to propagate along the preset path.

When optical devices such as a galvanometer and the like need to be connected, the light beam passing through the diaphragm usually needs to be reflected again so as to adjust the direction of the laser incident on the galvanometer.

In another specific embodiment, when the laser rotates with the turntable and the direction pointed by the laser changes, the laser with the changed propagation direction after being reflected continues to propagate towards the diaphragm, so that the laser beam passing through the diaphragm continues to propagate along the preset path, and is reflected again to change the propagation direction.

The laser rotating along with the rotary table is firstly emitted from a cavity of the rotary table, changes the propagation direction through at least 1-time reflection, and then continuously propagates towards the diaphragm, so that the laser beam passing through the diaphragm continuously propagates along a preset path.

The process the utility model discloses the laser of device correction can not only make the light beam after the diaphragm along predetermineeing the route and propagate, sets for the distance and sets for the contained angle and also keep unchangeable between the laser light path of its incident mirror that shakes under the arbitrary angle of revolving stage and revolving stage axis of revolution, enables laser and to the directional requirement of predetermineeing of work piece, and the facula shape that acts on the work piece also can remain stable to satisfy precision finishing's needs.

In order to improve the stability of the pointing direction of the laser to the workpiece, which meets the preset requirement, and the stability of the shape of a light spot acting on the workpiece, the pre-calibration is carried out before the laser beam enters the cavity channel, so that the laser beam forwards propagates along the direction (including parallel or coaxial) of the rotating shaft of the rotary table. Namely, the laser beam is adjusted in advance to be in a coaxial or parallel state with the rotary shaft of the rotary table as much as possible. Or closed-loop pointing control is carried out, namely the pointing of the laser to the workpiece is regulated in a real-time closed-loop manner through the fast reflecting mirror and the sensor before the light beam passes through the diaphragm.

The sensor is used for sensing the incident information of the laser, namely the incident angle information of the laser when the laser touches the sensing element and the position information of the laser on the sensing element are included. Usually, information of a two-dimensional coordinate system in which the laser spot on the sensor element is located is used as the position information. The laser beam has set position information on the sensor, and the actual position of the laser beam speed on the sensor is deviated from the set position due to factors such as stress, vibration, elastic deformation, temperature, rotation error and the like. When the sensor senses the incident laser, the sensor can obtain the position information, know the actual position and provide a basis for judging whether the laser deviates from the set position or not and whether the laser compensates or not. In a sensor, there is usually at least one sensing element, but in order to obtain more laser incidence information, it is preferable to use two or more sensing elements.

The setting position information should be understood as information that is set by debugging and can satisfy the precision machining requirements. Such as: the distance between the focusing spot of the laser beam and the rotary axis of the rotary table is always kept, namely, the rotary table rotates at any angle, and the distance deviation between the focusing spot and the rotary axis of the rotary table is less than or equal to 1 mu m. When the distance deviation between the obtained focusing light spot and the rotary axis of the turntable is less than or equal to 1 mu m after the laser beam (after compensation) enters the galvanometer, the rotary error of the laser light path is considered to be eliminated.

In a specific embodiment, when the turntable rotates, the sensor receives laser information (such as information emitted from the turntable or information incident on the turntable), senses incident information of the laser, and transmits the real-time incident information to the controller, the controller compares the real-time incident information with set position information to obtain an offset value, and when the offset value exceeds a set threshold value, the controller drives the reflection mechanism to adjust the laser light path in real time for compensation, so that the relative position of the compensated laser light path incident on the galvanometer and the rotary axis of the turntable is maintained.

The sensor is generally disposed at one end of the turntable where the laser beam enters or exits, and receives laser beam information. When the laser information receiving device is arranged at one emergent end, the laser information receiving device rotates around the rotary axis of the rotary table along with the rotary table to receive laser information, and particularly the laser information receiving device is arranged behind the reflector and receives the laser information refracted by the reflector.

The reflection mechanism, usually at least includes 1 piece of fast reflection mirror, is used for receiving the laser that comes out from ultrafast laser, and the instruction of controller, adjusts the reflection mirror and compensates the laser light path.

In another specific implementation mode, when the rotary table rotates, a sensor is arranged at one end of the laser, which is emitted or incident from the rotary table, the sensor receives laser information and transmits real-time incident information to the controller, the controller compares the real-time incident information with set position information to obtain an offset value, and when the offset value exceeds a set threshold value, the fast-reflecting mirror is driven;

the fast reflector reflects laser emitted from the ultrafast laser, and compensates a laser path after obtaining an instruction of the controller, so that a relative position relationship between the compensated laser path incident to the galvanometer and a rotary shaft axis of the rotary table is maintained.

In another specific implementation mode, when the rotary table rotates, a sensor is arranged at one end of the laser, which is emitted or incident from the rotary table, the sensor receives laser information and transmits real-time incident information to the controller, the controller compares the real-time incident information with set position information to obtain an offset value, and when the offset value exceeds a set threshold value, the fast reflection mirror is driven;

the fast reflector reflects laser emitted from the rotary table, and after the fast reflector obtains an instruction of the controller, the angle of the fast reflector is adjusted to compensate a laser path (generated deviation) caused by rotation of the rotary table.

The method of the utility model is applied to processing equipment with a plurality of moving shafts (such as a three-shaft machine tool, a four-shaft machine tool, a five-shaft machine tool and the like), and eliminates the influence of factors such as rotation, stress, vibration, elastic deformation, temperature, rotation error and the like of the turntable on the laser pointing direction and the light spot position after focusing, so that when the turntable rotates at any angle, the space distance of the laser light spot after focusing from the center of the rotating shaft on the rotating table surface can be kept.

The utility model provides a device that path is skew is rectified when directional change of laser is in order to implement when the directional change of laser and rectify the path skew, include:

a turntable, which performs a revolving motion, comprising channels for accommodating the propagation of the laser light;

the ultrafast laser, its laser that launches passes the revolving stage through the cavity;

the laser projection relay part is arranged on the rotary table, rotates around the rotary axis of the rotary table along with the rotary table, receives laser from the exit end of the cavity channel, and emits the laser after the light path direction of the laser is changed, and at least comprises a first reflector and a second reflector;

and a diaphragm receiving the light beam reflected from the first reflecting mirror.

The utility model discloses a device still includes:

and the light emitting component is arranged on the rotary table, rotates around the rotary axis of the rotary table along with the rotary table, receives the laser emitted by the laser projection relay component and focuses in the range of the rotary axis.

The utility model discloses a device still includes:

the sensor is used for acquiring real-time incident information of the laser;

the controller receives real-time incident information sent by the sensor and compares the real-time incident information with preset position information to obtain a position deviation value;

and the reflecting mechanism receives the laser emitted from the ultrafast laser and compensates the reflected laser light path after obtaining the instruction of the controller.

The utility model discloses a device, reflecting mechanism include 1 speculum at least. However, in order to obtain a better laser path compensation scheme, 2 mirrors are required. Further, each mirror is configured on a separate frame such that each mirror has at least 2 degrees of freedom that are adjustable, i.e., more than 4 degrees of freedom are provided by at least 2 mirrors to implement a laser compensation scheme.

A specific implementation mode of the reflecting mechanism comprises a third reflecting mirror and a fourth reflecting mirror, wherein the third reflecting mirror reflects laser to the fourth reflecting mirror after receiving the laser, and the fourth reflecting mirror reflects the laser towards the cavity channel after receiving the laser.

The device of the utility model, the laser projection relay part at least comprises 1 reflector, and is a double-sided polishing lens. The laser receiving device can be used for receiving laser reflected by the second reflecting mirror or directly receiving laser from the exit end of the cavity, so that the optical path direction of the laser is changed and then the laser is used as incident laser of the vibrating mirror.

A sensor is arranged behind the reflector, and the reflector refracts (transmits) a light beam to observe and detect laser spots and acquire real-time incident information of the laser.

In order to facilitate the reflected laser to be used as the incident laser of the vibrating mirror, a plurality of reflecting mirrors can be arranged between the vibrating mirror and the vibrating mirror to adjust the light path of the reflected laser.

The utility model provides a device, the revolving stage if: 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 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.

The utility model provides a device, laser projection relay part, light-emitting component rotate with the cavity revolving stage is synchronous. Specifically, the light emitting part is connected with the laser projection relay part, is driven by the hollow rotary table, and rotates around the rotating shaft.

The utility model provides a various devices are installed on machining equipment, for example: three linear motion shafts, a rotary motion shaft for fixing the workpiece and a laser beam rotary shaft 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, one of the linear shafts 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 along the Z shaft in a linear way), the other linear shaft is provided with a rotating and positioning mechanism, the device drives a workpiece to be processed to rotate and position (for example, the workpiece is arranged on the plane determined by the X shaft and the Y shaft), and the influences of factors such as stress, vibration, elastic deformation, temperature rise, rotation error and the like on the laser pointing direction and the light spot position after focusing are eliminated, so that when the turntable is at any angle, the space distance between the focused laser light spot and the center of the rotating shaft on the turntable surface is unchanged, the precision of laser processing is improved, and the device is beneficial to laser processing of parts with various specifications.

Another machining equipment will the utility model discloses the revolving stage of device is installed in the straight line epaxially, and the device is followed rectilinear movement, and the focusing facula that makes the laser that reachs the optical part and jet out is linear movement, rotates around the gyration pivot when light-emitting part, makes to make the laser facula distribute on the surface of revolution, adapts to various work piece processing.

The utility model discloses beneficial effect that technical scheme realized:

the device provided by the utility model, laser rotates along with the revolving stage for the directional change of laser is rectified propagation path with the diaphragm, and the partial light beam that deviates (if: the directional deviation of laser) takes place because of the gyration is selectively filtered, and make the laser beam through the diaphragm (promptly not deviate preset propagation path) continue to propagate along preset path, change the direction of propagation through the reflection again, still enable laser and keep according with the preset to the directional coincidence of work piece, the facula shape that acts on the work piece also remains stable, in order to satisfy precision finishing's needs.

The device provided by the utility model, through real-time perception laser facula position of sensor and directional information, and adjust reflection mechanism through the controller, compensate the skew that the laser light path produced, eliminate the revolving stage and rotate, stress, vibration, elastic deformation, factors such as temperature rise and gyration error are directional and the influence of facula position to focusing back laser, so that when the arbitrary angle of revolving stage, the space distance of revolving axle center department on the laser facula distance revolving stage face after the focus is unchangeable, laser beam machining precision has been improved.

The device provided by the utility model, with the vertical installation of the laser head of ultrafast laser instrument to downwards, do benefit to the ultrafast laser instrument and integrate on machining equipment, implement the precision finishing of laser.

The device provided by the utility model, set up the diaphragm between 2 adjacent reflectors in the relay part is thrown to laser, rectify the skew predetermined propagation path of laser that factors such as revolving stage rotation, stress, vibration, elastic deformation, temperature rise and gyration error were sent, do benefit to and carry out low-cost transformation to current machining equipment, do benefit to the ultrafast laser instrument and integrate on machining equipment, implement the precision finishing of laser.

Drawings

FIG. 1 is a schematic view of an embodiment of a prior art apparatus for laser machining;

FIG. 2 is a schematic diagram of an embodiment of a laser beam path of a conventional apparatus for laser machining;

FIG. 3 is a schematic diagram of another embodiment of a laser beam path of a prior art apparatus for laser machining;

FIG. 4 is a schematic view of an embodiment of the apparatus of the present invention;

FIG. 5 is an enlarged schematic view of an angle of the diaphragm shown in FIG. 4;

FIG. 6 is a schematic view of an embodiment of the apparatus of the present invention;

fig. 7 is a schematic view of another embodiment of the apparatus of the present invention;

FIG. 8 is a schematic view of a laser scribing a workpiece surface when the apparatus of the present invention is used to machine a workpiece;

fig. 9 is a schematic diagram of laser scoring of a workpiece surface after removal of the stop of the apparatus of the present invention.

Detailed Description

The technical solution of the present invention is described in detail below with reference to the accompanying drawings. The embodiments of the present invention are only used for illustrating the technical solutions of the present invention and not for limiting, although the present invention is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced with other equivalent solutions without departing from the spirit and scope of the present invention, which should be covered by the scope of the claims of the present invention.

In the method for machining by using laser provided by this embodiment, laser emitted from a laser emitter is first emitted into a section of cavity, then emitted from the cavity, and enters a laser projection relay component, and the laser projection relay component changes a propagation path of the laser, then emits the laser, and finally is received by a light emitting component and then emits the laser, so as to machine a workpiece. The laser light propagates in the cavity, either along a straight line or along a broken line. The laser propagates along a straight line at the outlet end of the cavity channel, the rotating shaft is an A shaft, a B shaft or a C shaft in a right-hand rectangular coordinate system, so that the laser emitted by the light emitting component is distributed around the rotating shaft, and the laser is focused in the range of the rotating shaft, namely in a rotating (circular) surface with the radius of 100mm taking the rotating shaft as a center, in particular on the rotating shaft line. The laser pointing direction is driven to change by the rotation of the revolving shaft so as to implement machining. In this embodiment, the cavity is in the Y-axis direction, the rotation axis is the B-axis, and the light-emitting component rotates around the B-axis.

FIG. 1 is a schematic diagram of an embodiment of a conventional apparatus for performing laser machining. As shown in fig. 1, the apparatus includes a laser transmitter 100, a cavity 200, a laser projection relay part 700, a light exit part 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 is coaxial or parallel to the rotation axis of the turntable 400 and emitted to the other end. The laser beam emitted from the cavity 200 is redirected by the laser projection relay member 700 and then received by the light emitting member 300, and the emitted laser beam 310 is focused within the range of the rotation axis 410 for processing the workpiece.

In this embodiment, the laser projection relay member 700 includes a first reflection mechanism 710 and a second reflection mechanism 720, the first reflection mechanism 710 receives the laser beam incident on the laser projection relay member and reflects the laser beam toward the second reflection mechanism 720, and the second reflection mechanism 720 receives the laser beam 730 reflected from the first reflection mechanism 710, reflects the laser beam 730 again, and emits the laser beam out of the projection relay member.

The laser projection relay unit 700 is driven by the turntable 400 to rotate around the rotation shaft 410, receives laser from the exit end of the cavity, changes the optical path direction of the laser, and emits the laser. The light emitting unit 300 rotates around the rotation axis 410 to emit the laser beam 310 for machining.

In a right-hand rectangular coordinate system, the turn table 400 is rotated about the Y-axis, and the axis about which the rotation is performed is 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 exit member 300 is rotated around the B axis, so that the emitted laser light is distributed around the B axis direction, and the laser light is machined in a rotating manner. The cavity 200 is arranged in the turntable 400, namely a straight tube type hollow cavity is arranged in one section of the turntable 400, 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 hollow rotary table 400 rotates, the cavity 200 disposed therein does not displace, so that the laser beam 110 passing through the cavity 200 always travels in a linear direction without deflection and is always received by the light emitting element 300. The light exit member 300 is continuously rotated around the B axis, and laser light is distributed around the B axis rotation direction.

After the device is provided with a multi-axis machining device, when the intersection angle of the laser light path 110 of the incident cavity and the rotating shaft 410 of the turntable is kept between 0 and 5 degrees, the laser projection relay part and the light emitting part also rotate around the rotating shaft 410 along with the rotation of the turntable, and laser used for machining is emitted from the light emitting part 300 and rotates around the rotating shaft 410 of the turntable together. The laser projection relay member follows the turn of the turn table, so that the laser pointing direction changes, such as: 1 °, 5 °, 10 °, 20 °, 30 °, 40 °, 50 °, 60 °, 70 °, 80 °, and 90 ° or more. In the actual production, because factors such as stress, vibration, temperature and elastic deformation inevitably occur, laser does not propagate along the axial direction of the rotary shaft of the rotary table when the rotary table rotates, and therefore laser propagation generates deviation. When the deviated laser is changed in direction by the laser projection relay component, the deviation degree of the deviated laser from the preset laser propagation path is further enlarged, so that the laser 310 emitted by the light emitting component is deviated, and the laser processing precision is influenced. Fig. 2 and 3 are schematic diagrams of another embodiment of a laser path of a conventional device for performing machining with laser, which schematically show that laser light emitted from the light emitting part 300 cannot fall at the same position in a case where the laser path 110 of the incident cavity and the rotation axis 410 of the turntable are not in a coaxial state when the relay part and the light emitting part rotate with the turntable. Therefore, the optical path still needs to be readjusted frequently, and the actual distance and the actual included angle between the laser optical path of the incident galvanometer and the rotation axis of the turntable deviate from the set distance and the set included angle, which takes a lot of time and is not beneficial to cost control.

For this reason, the present embodiment provides a method for correcting a path deviation when a laser direction is changed, in which laser light emitted from the turntable 400 is reflected for at least 1 time to change a propagation direction, and then is continuously propagated toward the diaphragm, so that the laser beam passing through the diaphragm is continuously propagated along a preset path. Fig. 4 is a schematic diagram of an embodiment of the present invention, and fig. 5 is an enlarged schematic diagram of an angle of the diaphragm shown in fig. 4. Referring to fig. 1, as shown in fig. 4 and 5, the laser projection relay assembly is rotated synchronously by the turntable 400, and in the operation process, the light beam 761 is affected by stress, vibration, temperature, elastic deformation and other factors, and the light beam 762 is obtained after the light beam 761 deviates. When the light beams 761, 762 are reflected by the mirror 731 and propagate towards the diaphragm 750, the laser beam 760 corresponding to a predetermined propagation path can be obtained through the diaphragm 750, i.e. the propagation direction is changed by reflection, for example: the reflected light changes the propagation direction and then enters the light emitting component 300, so that the light beam deviating from the preset propagation path can be corrected, when the laser and the turntable rotate synchronously and the propagation direction changes by 180 degrees or more, the direction of the laser to the workpiece is preset, and the shape of the light spot acting on the workpiece is also kept stable, so as to meet the requirement of precision machining.

Fig. 6 is a schematic diagram of an embodiment of the present invention. As shown in fig. 6, the apparatus of the present embodiment includes a turntable 400, an ultrafast laser 120, and a laser projection relay part 700. The turntable 400 is hollow and includes a channel for accommodating the propagation of the laser light. The ultrafast laser 120 is disposed on the support 600, the emitted laser 121 is reflected by the reflection mechanism 800 and then changes direction, and then is emitted into the cavity 200, and at the exit end of the cavity 200, the laser 121 propagates along a straight line.

The laser projection relay member 700 is disposed on the turntable 400 and rotates around the turntable rotation axis along with the turntable 400, receives the laser beam from the exit end of the cavity, changes the optical path direction of the laser beam, and emits the laser beam, and includes at least a first reflecting mirror 731 and a second reflecting mirror 721. The diaphragm 750 is disposed between the first reflecting mirror 731 and the second reflecting mirror 721, such that the laser beam reflected by the first reflecting mirror 731 changes its propagation direction, and then continues to propagate toward the diaphragm 750, such that the laser beam passing through the diaphragm 750 continues to propagate along a predetermined path. The laser beam is incident on the laser projection relay member to be emitted, during which the sum of changes in the propagation angle of the laser beam reaches 180 DEG or more. The laser beam is deflected by the laser projection relay unit 700 and received by the galvanometer 320 of the light emitting unit. The light-emitting component rotates around the rotating shaft and focuses on the range of the rotating shaft.

In order to improve the stability of the pointing direction of the laser to the workpiece, which meets the preset requirement, and the stability of the shape of a light spot acting on the workpiece, the pre-calibration is carried out before the laser beam enters the cavity channel, so that the laser beam forwards propagates along the direction (including parallel or coaxial) of the rotating shaft of the rotary table. Namely, the laser beam is adjusted in advance to be in a coaxial or parallel state with the rotary shaft of the rotary table as much as possible. Or closed-loop pointing control is carried out, namely real-time closed-loop adjustment is carried out on the pointing direction of the laser to the workpiece through the fast reflector and the sensor. Such as: when the turntable rotates, the sensor rotates around the rotation axis of the turntable together with the turntable, the sensor is arranged at one end of the laser emergent from the turntable, the sensor receives laser information and transmits real-time incident information to the controller, the controller compares the real-time incident information with set position information to obtain an offset value, and when the offset value exceeds a set threshold value, the reflecting mechanism is driven.

The reflecting mechanism receives the laser emitted from the ultrafast laser, and compensates the laser light path after obtaining the instruction of the controller, so that the relative position of the compensated laser light path entering the galvanometer and the rotary shaft axis of the rotary table is maintained.

Fig. 7 is a schematic diagram of another embodiment of the device of the present invention. As shown in fig. 7, 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 ultrafast laser 120 is disposed on the support 600, the emitted laser 121 is reflected by the reflection mechanism 800 and then changes direction, and then is emitted into the cavity 200, and the laser 121 is transmitted along a straight line at the exit end of the cavity 200. The laser beam is redirected by the laser projection relay unit 700 and then received by the galvanometer 320 of the light emitting unit. The light-emitting component rotates around the rotating shaft and focuses on the range of the rotating shaft.

The laser projection relay member includes at least 1 mirror which is a double-sided polished mirror. In this embodiment, the laser projection relay unit is provided with the second reflecting mirror 721 and the first reflecting mirror 731. Specifically, the first reflecting mirror 731 reflects the laser beam after receiving the laser beam, so that the beam propagates toward the diaphragm 750, and after passing through the diaphragm 750, the propagation path matches a predetermined path and directs toward the second reflecting mirror 721, and the second reflecting mirror 721 receives the laser beam and reflects the laser beam toward the vibrating mirror.

The sensor 900 is located behind the second mirror 721, and detects the laser spot from the exit end of the cavity by using the light transmitted from the second mirror, thereby obtaining real-time position information of the laser. A controller (not shown) receives the real-time position information from the sensor 900 and compares the real-time position information with the preset position information to obtain a position deviation value. When the position deviation value exceeds the threshold value, the relative position of the laser light path and the rotary shaft of the rotary table cannot be maintained, and then a command is sent to the reflecting mechanism. In this embodiment, two sensor elements are used to obtain the incident angle information of the laser and the position information of the laser on the sensor elements, respectively, so as to obtain more laser incident information.

After the reflecting mechanism 800 obtains the instruction of the controller, the laser from the ultrafast laser is adjusted, and the light path for emitting the laser is adjusted, so that the relative position of the laser light path 740 entering the galvanometer and the rotary shaft axis of the rotary table is maintained, and the change of the laser light path is compensated in real time. In this embodiment, the reflecting mechanism 800 includes a third mirror 810 and a fourth mirror 820, each of which is configured on a separate frame such that each mirror has at least 2 adjustable degrees of freedom, i.e., more than 4 degrees of freedom are provided by at least 2 mirrors to implement a laser compensation scheme. Specifically, after receiving the laser beam, the third reflector 810 reflects the laser beam to the fourth reflector 820, and after receiving the laser beam, the fourth reflector reflects the laser beam toward the cavity, so that the relative position of the laser path of the incident galvanometer and the rotary axis of the turntable is maintained. Preferably, the AOI of third mirror 810 and fourth mirror 820 are both 22.5 °.

In addition, the sensor 900 may be disposed before the laser incident turntable 400, and the laser spot from the cavity exit end may be detected by the light transmitted from the mirror, so as to obtain the real-time position information of the laser; or the reflecting mechanism 800 is placed on the turntable 400, all should be regarded as equivalent alternatives of the present technical solution.

The devices provided by the above embodiments are installed on a machining device, such as: three linear motion shafts, one rotary motion shaft for fixing the workpiece and one laser beam rotary shaft are combined to form a space five-shaft laser machining scheme, so that the workpiece can be machined in a multi-shaft mode, products with complex and various structures are manufactured, and the space five-shaft laser machining scheme is particularly suitable for precision machining of long-shaft parts. Such as: the machine tool is provided with at least three linear shafts, one of the linear shafts 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), the other linear shaft is provided with a rotating positioning mechanism, the rotating positioning of the processed workpiece is driven (for example, the workpiece is arranged on the plane determined by the X shaft and the Y shaft), the situation that the relative position of a light beam and a rotary table rotary shaft cannot be kept due to the factors such as stress, vibration, elastic deformation or temperature is eliminated, the precision of laser processing is improved, and the laser processing is favorably carried out on parts with various specifications.

The apparatus shown in fig. 6 of this embodiment is installed on a machine tool, a sample card is installed on a focal plane, the sample card rotates along with the B axis, after the laser is turned on and the B axis is driven to rotate 180 °, the sample card is observed by a 200-fold microscope, and an etching trace is only a circular pattern (see fig. 8) with a diameter corresponding to the diameter of a light spot, which shows that the light spot rotates along with the rotation of the B axis and does not displace.

The same test was performed with the stop removed from the device, and the sample card was observed with a 200-fold microscope, resulting in the nicks shown in FIG. 9. Compared with the graph of fig. 8, it can be seen that the position of the laser focusing point drifts along with the rotation of the axis B after the diaphragm is removed, the maximum deviation amount reaches more than 4 times of the diameter of the light spot in the experimental device, and obviously the requirement of fine machining cannot be met.

Claims

1. An apparatus for correcting a path deviation when a laser pointing direction is changed, comprising:

a turntable, which performs a rotary motion and comprises a cavity, wherein the cavity is used for accommodating a light path of laser;

the laser emitted by the ultrafast laser passes through the rotary table through the cavity;

the laser projection relay part is arranged on the rotary table, rotates around the rotary axis of the rotary table along with the rotary table, receives laser from the exit end of the cavity channel, and emits the laser after the light path direction of the laser is changed, and at least comprises a first reflector;

2. The apparatus for correcting a path deviation when a laser pointing direction is changed according to claim 1, further comprising:

3. The apparatus for correcting a path deviation when a laser pointing direction is changed according to claim 1, further comprising:

the sensor is used for acquiring real-time incident information of the laser;

and the reflecting mechanism receives the laser emitted from the ultrafast laser, compensates the reflected laser light path after obtaining the instruction of the controller, and keeps the distance from the focusing light spot to the rotary axis of the rotary table all the time, namely the deviation of the distance at any angle of the rotary table is less than or equal to 1 mu m.

4. The apparatus of claim 3, wherein the reflecting mechanism comprises at least 2 fast reflecting mirrors, each fast reflecting mirror having at least 2 adjustable degrees of freedom.

5. The apparatus according to claim 3, wherein the reflecting mechanism includes a third mirror and a fourth mirror, the third mirror reflects the laser light to the fourth mirror after receiving the laser light, and the fourth mirror reflects the laser light toward the cavity channel after receiving the laser light.

6. A machine tool comprising means for correcting path deviation when the laser pointing direction is changed as claimed in claim 1.