Combined laser processing head with an abrasive grain stream generated by a spray liquid jet and method for its operation

Abstract

Combined laser processing head with an abrasive grain stream generated by a spray liquid jet, characterized in that it comprises the following: - a spray mechanism comprising a connecting part (8) having a channel communicating with the interior of a nozzle (10) and the interior of a tube (1), and which is connected at one end to the tube (1) and at the other end to the nozzle (10) and projects into the nozzle (10), wherein the section of the connecting part (8) projecting into the nozzle (10) is provided with a flange (8-4) in close contact with the side wall of the nozzle (10) and together with the side wall of the nozzle (10) forms an annular cavity, wherein several through-holes are formed in the flange (8-4) which communicate with the annular cavity and the interior of the nozzle (10), wherein a liquid injection port (9) for injecting a saturated salt solution at a set pressure into the annular cavity is provided on the side wall of the nozzle (10) in the region of the annular cavity,which saturated salt solution flows through the through-holes in the annular cavity, which is completely filled with saturated salt solution, and is sprayed out of the nozzle (10), thereby preventing the solution from forming turbulence that would affect the irradiation and propagation of the laser beam; , - a cooling mechanism comprising a cooling cylinder (12) open at both ends, within which a cooling tube (13) is arranged, which serves to cool the saturated salt solution sprayed out of the nozzle (10) and flowing through the cooling cylinder (12) in such a way that it separates fine particles.

Description

Field of the invention

[0001] The present invention relates to the field of laser processing devices, in particular to a combined laser processing head with an abrasive grain stream generated by a spray liquid jet itself and a method for its operation. Technical background

[0002] Laser processing, as a non-contact process, requires no tools, offers high processing speeds, causes only minor surface deformations, and is suitable for a variety of material types. The inventor discovered that previous laser processing was mostly one-sided. This means that when processing a material to be vaporized, it is simply melted by the high temperature of the laser. This inevitably leads to the formation of so-called deformation layers and thus reduces the accuracy of laser processing. In addition, existing laser processing heads cannot be used for combined processing, but only for laser processing. This has resulted in the laser processing industry being at a relatively low level.

[0003] WO 2018 / 008 400 A1 relates to a laser processing device and a laser processing method.

[0004] US 2017 / 0 050 198 A1 relates to an optical processing nozzle and an optical processing device.

[0005] US 5 418 350 A discloses a coaxial nozzle for surface treatment by laser irradiation, with supply of powdered materials.

[0006] US 4 078 165 A relates generally to laser cutting machines and, more particularly, to improvements in manually fed laser cutting machines. Disclosure of the invention

[0007] In order to overcome the above-mentioned disadvantages of the prior art, it is the object of the present invention to provide a combined laser processing head with an abrasive grain stream generated by a spray liquid jet itself, which allows a reliable removal of deformation layers arising during laser processing and with which the laser processing accuracy can be increased and the surface roughness of a machined workpiece can be reduced.

[0008] To solve this problem, the invention proposes the following embodiments: A combined laser processing head with an abrasive grain stream generated by a spray liquid jet comprises: - an injection mechanism comprising a connecting part having a channel communicating with the interior of a nozzle and the interior of a tube, which is connected to the tube at one end and to the nozzle at the other end and projects into the nozzle, wherein the portion of the connecting part projecting into the nozzle is provided with a flange in tight contact with the side wall of the nozzle and, together with the side wall of the nozzle, forms an annular cavity, wherein a plurality of through holes are formed in the flange and communicate with the annular cavity and the interior of the nozzle, wherein a liquid injection opening for injecting a saturated salt solution at a set pressure into the annular cavity is provided in the region of the annular cavity on the side wall of the nozzle,which saturated salt solution flows through the through holes when the annular cavity is completely filled with the saturated salt solution and is sprayed out of the nozzle, thereby preventing the solution from forming turbulence that would affect the irradiation and propagation of the laser beam, - a cooling mechanism comprising a cooling cylinder open at both ends, within which a cooling tube is arranged, which serves to cool the saturated salt solution sprayed out of the nozzle and flowing through the cooling cylinder in such a way that it separates out fine grains.

[0009] By providing the nozzle and the cooling mechanism, a saturated salt solution can be jetted out during laser processing at the same time, and the saturated salt solution can be treated using the cooling mechanism to precipitate fine grains to generate an abrasive grain stream that impacts and grinds the surface of a workpiece to improve the surface quality of the workpiece.

[0010] It is further provided that the tube is connected at one end to the connecting part and at the other end to an end cap, wherein the end cap is provided with a connection for a laser transmission cable.

[0011] Furthermore, it is provided that a lens carrier is installed within the tube, to which a collimating lens and a focusing lens are attached, with the collimating lens being located near the connection.

[0012] It is further provided that the connecting part comprises a first connecting portion, a second connecting portion and an engagement portion, wherein the first connecting portion is threadably connected to the tube and the second connecting portion is threadably connected to the nozzle, while the engagement portion projects into the nozzle, has an outer diameter which is smaller than the inner diameter of the side wall of the nozzle, and together with the side wall of the nozzle forms the annular cavity.

[0013] Furthermore, it is provided that the contact surface of the flange to the nozzle is a conical surface, which can ensure a seal between the flange and the nozzle.

[0014] Furthermore, it is provided that a hollow separation tube is detachably connected to the flange, the interior of which is connected to the channel and which serves to separate the laser beam and the liquid jet from each other.

[0015] It is further provided that the tube is firmly connected to a first connecting plate, wherein the cooling mechanism is connected to the first connecting plate via a second connecting plate.

[0016] It is further provided that the second connecting plate is provided with an adjusting groove through which an adjusting bolt is passed, by means of which the second connecting plate is firmly connected to the first connecting plate.

[0017] It is further provided that the cooling tube is a spiral structure and is attached to the inner side surface of the cooling cylinder.

[0018] The present invention further discloses a method for operating a combined laser processing head with an abrasive grain stream generated by a spray liquid jet itself, in which a laser beam passes through the tube and exits the nozzle to laser process a workpiece, while a saturated salt solution is sprayed out of the nozzle at a set pressure after flowing through the annular cavity and the through-holes, wherein the emerging solution jet is cooled by the cooling mechanism such that the saturated salt solution precipitates fine grains that impact the workpiece and grind it.

[0019] Advantageous effects of the invention: 1. The combined machining head according to the invention offers the possibility of connecting a laser transmission cable and also allows the injection of a saturated salt solution at a set pressure via a liquid injection port into the nozzle to simultaneously emit a laser beam and a solution jet. The cooling mechanism allows the saturated salt solution sprayed from the nozzle to be cooled to such an extent that it precipitates microns that impinge on the surface of a workpiece and grind it. This ensures the reliable removal of deformation layers present on the surface of the workpiece, reduces the surface roughness of the workpiece, and improves the machining quality of the workpiece. 2. The saturated salt solution injected into the combined processing head according to the invention first completely fills the annular cavity and then flows out through the through holes, then is evenly sprayed out of the nozzle. This prevents the saturated salt solution from creating turbulence that would affect the irradiation and propagation of the laser beam. 3. The combined processing head according to the invention has a hollow separation tube with which the saturated salt solution and the laser beam can be separated from each other in order to further reduce the influence of the saturated salt solution on the propagation of the laser beam. 4. In the combined processing head according to the invention, the flange is in contact with the side wall of the nozzle via an inclined surface, so that when the connecting part is screwed into the nozzle, a seal between the flange and the side wall of the nozzle and thus an outlet of the saturated salt solution can be ensured only through the through holes. 5. In the combined machining head according to the invention, the adjustment groove and the adjustment bolt can be used to adjust the relative position of the cooling mechanism and the spray mechanism to each other and thus to cool the liquid jet at different positions, so that the spray liquid jet ejects fine grains at different positions to generate an abrasive grain stream. Presentation of the illustrations

[0020] The drawings attached to the description, which are part of the present application, serve to better understand the present application. The schematically illustrated embodiments of the present application and their description do not represent a limitation of the present application, but serve to explain the present application. They show: Fig. 1 shows a schematic representation of the entire structure of a first embodiment of the invention; Fig. 2 shows a schematic representation of the internal structure of an injection mechanism of the first embodiment of the invention; Fig. 3 shows the schematic structure of an end cover of the first embodiment of the invention; Fig. 4 shows the schematic structure of a tube of the first embodiment of the invention; Fig. 5 shows the schematic structure of a connecting part of the first embodiment of the invention; Fig. 6 shows the schematic structure of a nozzle of the first embodiment of the invention; Fig. 7 shows the schematic structure of a first connecting plate of the first embodiment of the invention; Fig. 8 shows the schematic structure of a cooling mechanism of the first embodiment of the invention. List of reference symbols 1 tube 1-1 Mounting plate 2 end covers 3 Connection 4 lens wearers 5 Bulging structure 6 Collimation lens 7 Focusing lens 8 Connecting part 8-1 First connecting section 8-2 Second connecting section 8-3 Intervention section 8-4 flange 8-5 through hole 9 Liquid injection port 10 nozzle 11 Hollow separator tube 12 cooling cylinders 13 Cooling pipe 14 First connecting plate 15 Second connecting plate 15-1 Adjustment groove Concrete embodiments

[0021] It is understood that the following detailed description is exemplary and intended to further explain the present application. Unless otherwise indicated herein, all technical or scientific terms used in this description are to be understood in a manner known to one of ordinary skill in the art.

[0022] It should be noted that the terms used herein do not limit the exemplary embodiments according to the present application, but merely serve to explain specific embodiments. A singular form includes a plural form unless the context expressly indicates otherwise. Furthermore, it is understood that the use of the term(s) "include" and / or "comprise" in this specification indicates the presence of a feature, a step, an operation, a device, and / or a combination thereof.

[0023] In the description of the present invention, terms such as "top," "bottom," "left," and "right" may appear. These terms refer only to the representation in the respective figure and do not limit the respective structure. They are intended solely to describe the invention and simplify the description. In other words, these terms neither implicitly nor explicitly indicate the positioning, design, and operation of the respective device or element in a predetermined position, so that no limitation of the invention exists here either.

[0024] As mentioned at the beginning in the "Technical Background," combined processing cannot be achieved with existing laser processing heads. This results in the presence of deformed layers on the surface of the respective workpiece caused by laser processing, which is associated with high surface roughness. Based on this, the present application proposes a combined laser processing head with an abrasive grain stream generated by a spray fluid jet.

[0025] Out of Fig. 1-8 show a combined laser processing head with an abrasive grain stream generated by a spray liquid jet itself, which in a first embodiment of a typical embodiment of the present application comprises a spray mechanism and a cooling mechanism, wherein the spray mechanism comprises a tube, a connecting part and a nozzle.

[0026] At the upper end of the tube 1, an end cap 2 is arranged via a threaded connection, in the center of which a connector 3 is provided. The tube can be connected to a laser transmission cable via the connector, so that a laser beam transmitted by the laser transmission cable can enter the tube through the connector and then exit the nozzle.

[0027] Within the tube is a lens carrier 4, which has a hollowed outer wall and whose lower end sits on a bulging structure 5 formed at the bottom of the tube. The lens carrier is firmly connected at its upper end to a collimating lens 6 and at its lower end to a focusing lens 7.

[0028] The connecting part 8 comprises a first connecting portion 8-1, a second connecting portion 8-2, and an engaging portion 8-3, which are integrally connected to one another. The first connecting portion has an internal thread structure that cooperates with an external thread structure at the end of the tube to establish a threaded connection to the tube. The second connecting portion has a smaller outer diameter than the first connecting portion and is provided with an external thread structure that cooperates with an internal thread structure formed at the end of the nozzle to establish a threaded connection to the nozzle 10. The engaging portion projects into the nozzle and is provided at its lower end with a flange 8-4 that is in tight contact with the inner surface of the side wall of the nozzle.The engagement portion has an outer diameter that is smaller than the inner diameter of the corresponding area of ​​the nozzle, so that an annular cavity is formed between the engagement portion and the side wall of the nozzle. In the present embodiment, the annular cavity is circular. However, it can also have a different shape. In the area of ​​the annular cavity, a liquid injection opening 9 is provided on the side wall of the nozzle, through which a saturated salt solution can be injected into the annular cavity at a set pressure. A saturated sodium chloride solution or a saturated solution of other types of salt can be used as the saturated salt solution.In the flange, a plurality of through holes 8-5 are formed evenly distributed along the circumference, whereby the saturated salt solution can flow out of the annular cavity through the through holes and is sprayed out via a spray opening arranged in the lower region of the nozzle.

[0029] The flange is an inverted conical structure, with the surface of the flange that contacts the inner surface of the nozzle sidewall being a conical surface. The angled contact surface ensures the greatest possible sealing effect when the connector is screwed into the nozzle, thus preventing the saturated salt solution from escaping solely through the through holes.

[0030] The second connecting section, together with the inner wall of the nozzle, forms an annular cavity, allowing a spray fluid jet conveyed from one direction to first completely fill the annular cavity and then flow out through the through holes evenly spaced along the circumference of the flange, before being evenly sprayed out of the nozzle. This prevents the fluid jet from creating turbulence that would affect the irradiation and propagation of the laser beam.

[0031] In the center of the flange, a hollow separation tube 11 is provided via a threaded connection, the interior of which is connected to the channel and with which the solution beam and the laser beam can be separated from each other in order to further reduce the influence of the solution beam on the propagation of the laser beam.

[0032] The cooling mechanism is located below the spray mechanism and comprises a cooling cylinder 12 open at both ends. A spiral cooling tube 13 is attached to the inner cylindrical surface of the cooling cylinder, which can receive the saturated salt solution sprayed out of the spray mechanism. A coolant can be introduced into the cooling tube, with the upper end of the cooling tube serving as the coolant outlet and the lower end as the coolant inlet. The cooling tube serves to cool the saturated salt solution entering the cooling cylinder so that the saturated salt solution separates out fines to generate an abrasive grain stream.

[0033] Symmetrically arranged mounting plates 1-1, each provided with a threaded hole, are attached to the outer surface of the tube wall. The tube is firmly connected to a first connecting plate 14 via the threaded holes in the mounting plates and fastening bolts. The first connecting plate is an L-shaped structure and serves to connect the tube, the nozzle, and the connecting part to another device.

[0034] The cooling cylinder is connected via a bolt to a second connecting plate 15, in which an adjustment groove 15-1 is formed, through which an adjustment bolt passes, connecting the second connecting plate to the first connecting plate. The adjustment groove and the adjustment bolt allow adjustment of the relative position of the nozzle and the cooling mechanism to each other, thus cooling the spray fluid jet at different positions. The spray fluid jet ejects ultrafine grains at different positions to generate an abrasive grain stream. Second embodiment

[0035] The present embodiment discloses a method for operating a combined laser processing head with an abrasive grain stream generated by a spray liquid jet itself, in which a saturated salt solution (a saturated sodium chloride solution) is injected into the nozzle at a set pressure via the liquid injection port, and the tube is connected to a laser transmission cable via the connector, so that a laser beam transmitted through the laser transmission cable enters the tube through the connector, enters the channel after passing through the collimating lens and the focusing lens, and then exits through the injection port arranged in the lower region of the nozzle after passing through the inner cavity of the hollow separation tube, to laser process a workpiece.At the same time, a saturated salt solution is injected at a set pressure through the fluid injection port into the annular cavity. When the annular cavity is completely filled, it flows out through the through holes and is sprayed out of the nozzle. As the solution flows through the cooling cylinder, it is cooled by the cooling tube, causing the saturated salt solution to precipitate microns. These microns are sprayed out along with the saturated salt solution to impact and grind the surface of the workpiece, thereby removing the deformation layers created during laser processing. This reduces the surface roughness of the workpiece and improves the machining quality.

[0036] So far, the specific embodiments of the invention have been described with reference to the figures, which should not be construed as limiting the scope of the invention. Those skilled in the art will appreciate that any modification or variation that can be deduced from the embodiments of the invention without any inventive step falls within the scope of the invention.

Claims

[1] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet, characterized by that it includes: - an injection mechanism comprising a connecting part (8) having a channel communicating with the interior of a nozzle (10) and the interior of a tube (1), which is connected at one end to the tube (1) and at the other end to the nozzle (10) and projects into the nozzle (10), wherein the portion of the connecting part (8) projecting into the nozzle (10) is provided with a flange (8-4) in tight contact with the side wall of the nozzle (10) and, together with the side wall of the nozzle (10), forms an annular cavity, wherein a plurality of through holes are formed in the flange (8-4) which communicate with the annular cavity and the interior of the nozzle (10), wherein a liquid injection opening (9) for injecting a saturated salt solution at a set pressure into the annular cavity is provided in the region of the annular cavity on the side wall of the nozzle (10),which saturated salt solution flows through the through-holes and is sprayed out of the nozzle (10) when the annular cavity is completely filled with the saturated salt solution, thereby preventing the solution from forming turbulence that would influence the irradiation and propagation of the laser beam; - a cooling mechanism comprising a cooling cylinder (12) open at both ends, within which a cooling pipe (13) is arranged, which serves to cool the saturated salt solution sprayed out of the nozzle (10) and flowing through the cooling cylinder (12) in such a way that it separates out very fine grains. [2] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 1, characterized bythat the tube (1) is connected at one end to the connecting part (8) and at the other end to an end cover (2), wherein the end cover (2) is provided with a connection (3) for a laser transmission cable. [3] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 2, characterized by that a lens carrier (4) is installed within the tube (1), to which a collimating lens (6) and a focusing lens (7) are attached, the collimating lens (6) being located near the connection (3). [4] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 1, characterized byin that the connecting part (8) comprises a first connecting section (8-1), a second connecting section (8-2) and an engagement section (8-3), wherein the first connecting section (8-1) is threadably connected to the tube (1) and the second connecting section (8-2) is threadably connected to the nozzle (10), while the engagement section (8-3) projects into the nozzle (10), has an outer diameter which is smaller than the inner diameter of the side wall of the nozzle (10), and together with the side wall of the nozzle (10) forms the annular cavity. [5] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 1, characterized by that the contact surface of the flange (8-4) to the nozzle (10) is a conical surface. [6] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 1, characterized bythat a hollow separating tube (11) is detachably connected to the flange (8-4), the interior of which is connected to the channel. [7] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 1, characterized by that the tube (1) is fixedly connected to a first connecting plate (14), wherein the cooling mechanism is connected to the first connecting plate (14) via a second connecting plate (15). [8] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 7, characterized by that the second connecting plate (15) is provided with an adjusting groove (15-1) through which an adjusting bolt is passed, via which the second connecting plate (15) is firmly connected to the first connecting plate (14). [9] Combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to claim 1, characterized by that the cooling tube (13) is a spiral structure and is attached to the inner side surface of the cooling cylinder (12). [10] Method for operating a combined laser processing head with an abrasive grain stream generated by a spray liquid jet according to one of claims 1-9, characterized by that a laser beam passes through the tube (1) and exits the nozzle (10) in order to process a workpiece by means of a laser, while a saturated salt solution is sprayed out of the nozzle (10) at a set pressure after flowing through the annular cavity and the through-holes, the emerging solution jet being cooled by the cooling mechanism in such a way that the saturated salt solution precipitates fine grains which impinge on the workpiece and grind it.

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