Power monitoring device, laser printing equipment and control method

Abstract

The present application provides a power monitoring device, laser printing equipment and control method. The power monitoring device includes a base, a light input tube, a light output tube, a wedge mirror assembly and a detection assembly. During the laser printing process, the laser emits laser light to the power monitoring device. At this time, the laser enters the power monitoring device through the light input tube. Part of the laser light will pass through the wedge mirror assembly and then be emitted from the light output tube for laser printing. Another part of the laser light will be reflected at the wedge mirror assembly to the detection assembly for power detection. In this way, power monitoring can be performed while laser printing is being implemented to analyze whether the laser power is attenuated, to ensure that the laser can provide sufficient molten pool energy, and to ensure the forming quality of laser printing.

Description

Technical Field

[0001] The present application relates to the field of laser monitoring technology, and in particular to a power monitoring device, laser printing equipment, and a control method. Background Art

[0002] Selective laser melting (SLM) is a key branch of metal 3D printing technology. SLM uses a focused laser spot to selectively and rapidly melt metal powder in a designated area on a powder bed, solidifying it into a part of any shape. The entire process uses a laser as the energy source, scanning the powder bed layer by layer along a pre-planned path, melting and solidifying the powder to ultimately produce the final part.

[0003] However, due to aging and loss of components, damage to optical fibers under long-term high-power use, ambient temperature fluctuations and other reasons, the laser may experience power attenuation. If not maintained in time, the laser printing molten pool may lack energy, affecting the forming quality. Summary of the Invention

[0004] In view of the above, it is necessary to provide a power monitoring device, a laser printing device and a control method to ensure the forming quality of laser printing.

[0005] According to a first aspect of the present application, a power monitoring device is provided, comprising: a base, a light input tube, a light output tube, a wedge mirror assembly, and a detection assembly, wherein the light input tube and the light output tube are respectively connected to two ends of the base; the wedge mirror assembly is arranged in the base and located between the light input tube and the light output tube; the detection assembly is connected to the light input tube; when laser light enters the light input tube along an incident direction and passes through the wedge mirror assembly, a portion of the laser light is transmitted at the wedge mirror assembly and emitted from the light output tube along an exit direction; another portion of the laser light is reflected at the wedge mirror assembly and emitted toward the detection assembly along the reflection direction; the incident direction is parallel to the exit direction, and there is an angle between the incident direction and the exit direction.

[0006] In some embodiments, the wedge mirror assembly includes a first wedge mirror and a second wedge mirror. The first wedge mirror has a first wedge angle of 0.5° and is disposed at one end of the base body close to the light incident tube; the second wedge mirror has a second wedge angle of -0.8° and is disposed at one end of the base body close to the light output tube.

[0007] In some embodiments, the base materials of the first wedge mirror and the second wedge mirror are both silicon, and the refractive index of the first wedge mirror and the second wedge mirror are both 3.5.

[0008] In some embodiments, the first wedge mirror and the second wedge mirror both have coating layers, and the coating layers include a first layer for reducing surface reflectivity, a second layer for matching a high refractive index phase, and a third layer for matching and optimizing substrate impedance.

[0009] In some embodiments, the power ratio of the laser directed toward the detection component to the laser emitted from the light output tube is 1:9.

[0010] In some embodiments, a spacer is built into the base, and a first groove for accommodating the first wedge mirror and a second groove for accommodating the second wedge mirror are respectively provided on both sides of the spacer; the first wedge mirror is configured with a first pressure ring and a first gasket; the first pressure ring presses the side of the first wedge mirror away from the first groove through the first gasket, and is threadedly connected to the base; the second wedge mirror is configured with a second pressure ring and a second gasket; the second pressure ring presses the side of the second wedge mirror away from the second groove through the second gasket, and is threadedly connected to the base.

[0011] In some embodiments, a first compensation angle is formed between the two sides of the first washer, and the sum of the first compensation angle and the first wedge angle is 0; and / or, a second compensation angle is formed between the two sides of the second washer, and the sum of the second compensation angle and the second wedge angle is 0.

[0012] In some embodiments, the base is provided with a first heat exchange port and a second heat exchange port, and the spacer is provided with a first through hole connected to the first heat exchange port and a second through hole connected to the second heat exchange port.

[0013] The second aspect of the present application provides a laser printing device, including a laser, a galvanometer, a field lens and a power monitoring device as in the first aspect. When the laser emits laser light to the power monitoring device, the laser light emitted by the power monitoring device enters the galvanometer and the field lens.

[0014] The third aspect of the present application provides a control method, which is applied to a laser printing device such as the second aspect. The control method includes: obtaining monitoring power in real time during the printing process of the laser printing device, wherein the monitoring power is the power value obtained by the detection component performing power detection on the laser in the reflected light path; and triggering an alarm action in response to the monitoring power meeting a preset abnormal condition.

[0015] Through the power monitoring device, laser printing equipment and control method provided by the present application, during the laser printing process, the laser emits laser light to the power monitoring device. At this time, the laser enters the power monitoring device through the light input tube, and part of the laser light will pass through the wedge mirror assembly and then be emitted from the light output tube to achieve laser printing. Another part of the laser light will be reflected at the wedge mirror assembly to the detection assembly for power detection. In this way, power monitoring can be performed while laser printing is being achieved to analyze whether the laser power is attenuated, ensure that the laser can provide sufficient molten pool energy, and ensure the forming quality of laser printing. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of the laser printing device provided in this application.

[0017] Figure 2 This is a schematic diagram of the structure of the power monitoring device provided in this application.

[0018] Figure 3 Schematic diagram of the optical path of the power monitoring device provided in this application.

[0019] Figure 4 This is a schematic diagram of an exploded view of the power monitoring device provided in this application.

[0020] Figure 5 This is a schematic structural diagram of the first heat exchange port and the second heat exchange port provided in this application.

[0021] Figure 6 This is a flow chart of the control method provided in this application.

[0022] Description of main component symbols

[0023] 100. Power monitoring device; 200. Laser; 300. Optical fiber; 400. Beam expansion and collimation module; 500. Galvanometer; 600. Field mirror; 10. Base; 11. First heat exchange port; 12. Second heat exchange port; 20. Wedge mirror assembly; 21. First wedge mirror; 22. Second wedge mirror; 30. Light input tube; 31. Incident channel; 32. Reflection channel; 40. Detection assembly; 50. Light output tube; 51. Output channel; 60. Spacer; 61. First groove; 62. Second groove; 63. First through hole; 64. Second through hole; 70. First pressure ring; 71. First gasket; 80. Second pressure ring; 81. Second gasket. DETAILED DESCRIPTION

[0024] In the description of the embodiments of the present application, when an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be a centrally arranged element at the same time. When an element is considered to be "set on" another element, it may be directly set on the other element or there may be a centrally arranged element at the same time. In the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection, or it may be indirectly connected through an intermediate medium, or it may be internal communication between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0025] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0026] In related technologies, the laser propagation path in laser printing equipment typically consists of: laser, beam expander, galvanometer, field lens, window protection lens, and powder bed. However, due to factors such as aging or wear of laser components, damage to optical fibers caused by long-term high-power use, and ambient temperature fluctuations, laser power may decay, resulting in insufficient melt pool energy and reduced build quality.

[0027] To this end, the embodiments of the present application provide a power monitoring device, a laser printing device, and a control method, which can monitor the laser power, ensure that the laser can provide sufficient molten pool energy, and guarantee the forming quality of laser printing.

[0028] The present application first provides a power monitoring device, which is applied to a laser printing device.

[0029] like Figure 1 As shown, in the example of this application, the laser printing device includes a laser 200, a power monitoring device 100, a galvanometer 500, and a field lens 600. The laser light emitted by the laser 200 can be injected into the power monitoring device 100. After the power of the laser light is detected by the power monitoring device 100, the laser light is emitted from the power monitoring device 100 to the galvanometer 500 and the field lens 600. The focused light spot output by the field lens 600 is irradiated onto the powder bed, so that the laser energy acts on the metal powder, realizing laser 3D printing.

[0030] Specifically, the laser printing device also includes an optical fiber 300 and a beam expansion and collimation module 400. The laser 200, optical fiber 300, beam expansion and collimation module 400, power monitoring device 100, galvanometer 500, and field lens 600 are connected in sequence. The laser light emitted by the laser 200 is transmitted to the beam expansion and collimation module 400 via the optical fiber 300. The beam expansion and collimation module 400 converts the laser beam at the optical fiber 300 into collimated parallel light, while appropriately expanding the spot diameter to ensure that the laser light enters the power monitoring device 100 at a uniform incident angle. After passing through the power monitoring device 100, the laser light enters the galvanometer 500 and field lens 600.

[0031] Please also refer to Figure 2In this embodiment, the power monitoring device 100 includes a base 10, a wedge lens assembly 20, a light input tube 30, a detection assembly 40, and a light output tube 50. The base 10 is hollow, and the light input tube 30 and the light output tube 50 are connected to the base 10 at both ends. The wedge lens assembly 20 is disposed within the base 10 and located between the light input tube 30 and the light output tube 50. The detection assembly 40 is connected to the light input tube 30.

[0032] When laser light enters the light-input tube 30 along the incident direction and passes through the wedge mirror assembly 20, a portion of the laser light is transmitted by the wedge mirror assembly 20 and exits the light-output tube 50 along the exit direction. Another portion of the laser light is reflected by the wedge mirror assembly 20 and exits the light-output tube 50 along the reflection direction. The incident direction and the exit direction are parallel and form an angle between them.

[0033] Please also refer to Figure 3 During light propagation, the laser forms an incident optical path within the light input tube 30 that extends along the incident direction. The laser forms an exit optical path within the light exit tube 50 that extends along the exit direction. Most of the laser light is transmitted and refracted by the wedge mirror assembly 20, forming an intermediate optical path between the incident and exit optical paths. A small portion of the laser light is reflected by the wedge mirror assembly 20, forming a reflected optical path that extends along the reflection direction.

[0034] Among them, the incident light path is Figure 3 The line connecting point A to point B in the figure is shown. The reflected light path is Figure 3 The lines from point B to point G, point C to point H, and point D to point I are shown. Figure 3 The lines from point B to point C and from point D to point E are shown in the figure. Figure 3 In the example of the present application, the incident light path is perpendicular to the reflected light path. It is worth noting that the connecting lines in the diagram only indicate the propagation path and direction of the light, and do not represent the amount or intensity of the light.

[0035] In the example of the present application, the laser 200 uses a laser generator with an incident power of 500W, which can emit an infrared laser of 1050nm. The power ratio of the laser emitted to the detection component 40 to the laser emitted from the light-emitting tube 50 is 1:9, that is, the power ratio of the laser in the reflected light path to the laser in the outgoing light path is 1:9. Among them, the power ratio in this embodiment allows a certain error, as long as the error between the actual value of the power ratio and the preset value is within the specified range. It can be understood that the power ratio can be configured according to the incident power of the laser 200 and the range of the detection component 40. On the one hand, it is ensured that most of the laser (90% power) is emitted from the light-emitting tube 50 to provide sufficient molten pool energy, and on the other hand, a small part of the laser (10% power) is injected into the detection component 40 to ensure that the laser power is within the range corresponding to the detection component 40.

[0036] During the laser printing process, the laser 200 emits laser light to the power monitoring device 100. At this time, the laser light enters the power monitoring device 100 through the light input tube 30. Part of the laser light will pass through the wedge mirror assembly 20 and then be emitted from the light output tube 50 to achieve laser printing. Another part of the laser light will be reflected at the wedge mirror assembly 20 to the detection assembly 40 for power detection. In this way, power monitoring can be performed while laser printing is being achieved to analyze whether the laser 200 has power attenuation, ensure that the laser 200 can provide sufficient molten pool energy, and ensure the forming quality of laser printing.

[0037] On the other hand, the laser output by the power monitoring device 100 can be output to the galvanometer 500 and the field lens 600. Compared with the power monitoring function of the laser 200, the power monitoring device 100 can perform real-time power monitoring at a position closer to the user end, avoiding power attenuation caused by abnormalities in the intermediate transmission section, and the monitoring is more accurate.

[0038] In some embodiments, the wedge mirror assembly 20 includes a first wedge mirror 21 and a second wedge mirror 22. The first wedge mirror 21 and the second wedge mirror 22 are arranged in series, so that laser light passing through the wedge mirror assembly 20 can pass through the first wedge mirror 21 and the second wedge mirror 22 in sequence. The length of the substrate 10 is defined as the first direction. The first wedge mirror 21 and the second wedge mirror 22 are spaced apart along the first direction. The first wedge mirror 21 is positioned at the end of the substrate 10 closest to the light input tube 30, and the second wedge mirror 22 is positioned at the end of the substrate 10 closest to the light output tube 50. The first wedge mirror 21 is generally parallel to the second direction, with both the incident and reflected directions forming an angle with the second direction. The second wedge mirror 22 is generally parallel to the first wedge mirror 21.

[0039] Specifically, the first wedge angle (i.e., angle α shown in the figure) of the first wedge mirror 21 is oriented in the opposite direction to the second wedge angle (i.e., angle β shown in the figure) of the second wedge mirror 22. The angle direction refers to the direction of the acute angle's opening. The first wedge angle of the first wedge mirror 21 is 0.5°, and the thickness of the first wedge mirror 21 is 10 mm. The second wedge angle of the second wedge mirror 22 is -0.8°, and the thickness of the second wedge mirror 22 is 10 mm. Both the first and second wedge mirrors 21 and 22 are made of silicon, and the refractive index of each is 3.5.

[0040] As can be understood, the first wedge mirror 21 and the second wedge mirror 22 form a series combination with an inverse angle. The first wedge mirror 21 deflects light toward the thick end of the wedge angle, while the second wedge mirror 22 deflects it in the opposite direction to compensate for the angular deviation. Thus, when laser light propagating along the incident direction passes through the first and second wedge mirrors 21, 22 in sequence and exits the light output tube 50 along the output direction, the incident direction remains parallel to the output direction, ensuring that the incident and output light are parallel, thus avoiding the problem of insufficient energy in the molten pool during laser printing.

[0041] The first wedge mirror 21 and the second wedge mirror 22 have a wedge angle difference. When the laser passes through the first wedge mirror 21 and the second wedge mirror 22, an asymmetric refraction path is generated, causing the laser to deviate in the horizontal direction (i.e., perpendicular to the incident direction). The offset distance is calculated starting from the position where the laser reaches the first wedge mirror 21 from the light-incident tube 30 (i.e., Figure 3 The end point of the offset distance calculation is the position where the laser enters the light-emitting tube 50 from the second wedge mirror 22 (i.e. Figure 3 The precise 4.3mm offset ensures that the laser enters the galvanometer 500 and field lens 600 within a controllable range, guaranteeing processing accuracy.

[0042] It is worth noting that the specific arrangement angle of the first wedge mirror 21 and the second wedge mirror 22 (i.e., the angle between the second direction and the incident direction) can be set based on the predetermined physical parameters of the first wedge mirror 21 and the second wedge mirror 22 (such as wedge angle, thickness, substrate material, refractive index, etc.) to achieve the effect of parallelizing the incident light and the outgoing light. In the example of this application, the arrangement angle of the first wedge mirror 21 and the second wedge mirror 22 can be 45°.

[0043] In some embodiments, each mirror surface of the first wedge mirror 21 and the second wedge mirror 22 has a coating layer, which includes a first layer for reducing surface reflectivity, a second layer for matching the high refractive index phase, and a third layer for matching and optimizing the substrate impedance. The thickness of the layer is 180nm. The first layer forms the lowest refractive index layer to buffer the refractive index mutation between air and other layers and control the single interface reflectivity within the specified range.

[0044] The second layer is The first layer is made of a high refractive index material as a transition layer to match the light phase with the refractive index of the wedge mirror (n=3.5) to reduce the energy loss in the destructive interference region.

[0045] The third layer is layer, with a thickness of 185nm, and the third layer as the impedance adaptation layer of the silicon base material to alleviate The refractive index difference between the material refractive index (n=2.4) and the refractive index of silicon (n=3.5) suppresses reflection at the silicon substrate interface and protects the first wedge mirror 21 and the second wedge mirror 22 from chemical corrosion of the second layer.

[0046] It can be understood that the coating layer uses a combination of the first, second and third layers, and is configured for a 1050nm wavelength infrared laser and a wedge mirror on a silicon substrate, so that the power ratio of reflected light to output light is approximately 1:9. 90% of the output light is used to meet high-power processing requirements, while 10% of the reflected light provides a reliable signal source for power monitoring.

[0047] Please also refer to Figure 4 In some embodiments, the base 10 is cylindrical and has an internal cavity formed therein. The cavity extends through both ends of the base 10 to form an opening, and the axial direction of the base 10 is its length. A spacer 60 is built into the base 10. Two surfaces of the spacer 60 are provided with a first groove 61 for accommodating the first wedge mirror 21 and a second groove 62 for accommodating the second wedge mirror 22, respectively.

[0048] The first wedge mirror 21 is equipped with a first pressing ring 70 and a first washer 71. The first pressing ring 70, through the first washer 71, presses against the side of the first wedge mirror 21 away from the first groove 61 and is threadedly connected to the base 10. The second wedge mirror 22 is equipped with a second pressing ring 80 and a second washer 81. The second pressing ring 80, through the second washer 81, presses against the side of the second wedge mirror 22 away from the second groove 62 and is threadedly connected to the base 10.

[0049] Exemplarily, the spacer 60 is annular and fixed to the middle portion of the base 10. The outer diameter of the spacer 60 is consistent with the inner diameter of the base 10. The diameter of the first wedge mirror 21 is consistent with the diameter of the second wedge mirror 22, and the inner diameter of the spacer 60 is smaller than the diameter of the first wedge mirror 21. A first groove 61 is formed on the side of the spacer 60 facing the light input tube 30. The depth of the first groove 61 is less than the thickness of the first wedge mirror 21. The inner diameter of the first groove 61 is consistent with the diameter of the first wedge mirror 21. The first wedge mirror 21 is partially embedded in the first groove 61. A second groove 62 is formed on the side of the spacer 60 facing the light output tube 50. The depth of the second groove 62 is less than the thickness of the second wedge mirror 22. The inner diameter of the second groove 62 is consistent with the diameter of the second wedge mirror 22. The second wedge mirror 22 is partially embedded in the second groove 62. A distance is left between the first groove 61 and the second groove 62 so as to maintain a distance between the first wedge mirror 21 and the second wedge mirror 22 . The length of the distance can be configured according to actual needs.

[0050] Exemplarily, the first pressing ring 70 is annular in shape and has a first threaded portion disposed around its circumference. An internally threaded surface is disposed near the opening of the base 10 at one end of the light-entering tube 30. The first pressing ring 70 is threadedly connected to the base 10 via the first threaded portion and abuts against a surface of the first washer 71 facing away from the first wedge mirror 21. The first pressing ring 70, the first washer 71, and the spacer 60 cooperate to position and secure the first wedge mirror 21.

[0051] Exemplarily, the first washer 71 is annular and is disposed on the surface of the first wedge mirror 21 exposed to the first groove 61 and distributed circumferentially around the first wedge mirror 21. Made of polytetrafluoroethylene (PTFE), the first washer 71 mitigates thermal expansion differences between the first wedge mirror 21 and the spacer ring 60 and the first pressure ring 70, and absorbs vibration energy from the device through its own elasticity.

[0052] The two surfaces of the first washer 71 are not parallel. A first compensation angle (i.e., α' in the figure) is formed between the surface of the first washer 71 facing the first wedge mirror 21 and the surface of the first washer 71 facing the first pressure ring 70. The sum of the first compensation angle and the first wedge angle is 0, that is, the absolute value of the first compensation angle is equal to the absolute value of the first wedge angle, and the angular direction of the first compensation angle is opposite to the angular direction of the first wedge angle. In this embodiment, the first compensation angle is -0.5°.

[0053] In this way, the first washer 71 adapts to the wedge angle of the first wedge mirror 21, so that the first washer 71 and the first wedge mirror 21 form a combination with two parallel surfaces. The surface of the first pressure ring 70 facing the first washer 71 and the bottom surface of the first groove 61 are both perpendicular to the direction of the extrusion force of the first pressure ring 70. When the first pressure ring 70 presses against the first wedge mirror 21 through the first washer 71, the extrusion force direction of the first pressure ring 70 and the thread direction of the first threaded portion are perpendicular to the wedge surface of the first wedge mirror 21. This ensures that the locking force of the first pressure ring 70 is consistent with the thread direction of the first threaded portion, thereby evenly distributing the locking stress and preventing localized compression that may cause lens cracking.

[0054] Exemplarily, the second pressing ring 80 is annular and has a second threaded portion disposed around its circumference. An internally threaded surface is disposed near the opening of the base 10 at one end of the light-emitting tube 50. The second pressing ring 80 is threadedly connected to the base 10 via the second threaded portion and abuts against the surface of the second washer 81 facing away from the second wedge mirror 22. The second pressing ring 80, the second washer 81, and the spacer 60 cooperate to position and secure the second wedge mirror 22.

[0055] Exemplarily, the second washer 81 is annular and is disposed on the side of the second wedge mirror 22 exposed in the second groove 62, and is distributed circumferentially around the second wedge mirror 22. Made of polytetrafluoroethylene (PTFE), the second washer 81 can mitigate thermal expansion differences between the second wedge mirror 22 and the spacer ring 60 and the second pressure ring 80, and absorb vibration energy from the device through its own elasticity.

[0056] The two surfaces of the second washer 81 are not parallel. A second compensation angle (i.e., β' in the figure) is formed between the surface of the second washer 81 facing the second wedge mirror 22 and the surface of the second washer 81 facing the second pressure ring 80. The sum of the second compensation angle and the second wedge angle is 0, that is, the absolute value of the second compensation angle is equal to the absolute value of the second wedge angle, and the angular direction of the second compensation angle is opposite to the angular direction of the second wedge angle. In this embodiment, the second compensation angle is 0.8°.

[0057] In this way, the second washer 81 adapts to the wedge angle of the second wedge mirror 22, so that the second washer 81 and the second wedge mirror 22 form a combination with two parallel surfaces. The side of the second pressing ring 80 facing the second washer 81 and the bottom surface of the second groove 62 are both perpendicular to the direction of the extrusion force of the second pressing ring 80. When the second pressing ring 80 presses against the second wedge mirror 22 through the second washer 81, the extrusion force direction of the second pressing ring 80 and the thread direction of the second threaded portion are perpendicular to the wedge surface of the second wedge mirror 22. This ensures that the locking force of the second pressing ring 80 is consistent with the thread direction of the second threaded portion, thereby evenly distributing the locking stress and preventing localized compression that may cause lens cracking.

[0058] Please also refer to Figure 5 In some embodiments, the base 10 is provided with a first heat exchange port 11 and a second heat exchange port 12, which are spaced apart around the circumference of the base 10. The spacer 60 is provided with a first through-hole 63 connected to the first heat exchange port 11 and a second through-hole 64 connected to the second heat exchange port 12. The first through-hole 63 and the second through-hole 64 respectively penetrate the inner and outer sides of the spacer 60 in the radial direction of the spacer 60, and the first through-hole 63 and the second through-hole 64 are both connected to the spacing space between the first wedge mirror 21 and the second wedge mirror 22.

[0059] The first heat exchange port 11 and the second heat exchange port 12 are respectively used to connect to a heat dissipation device. The heat dissipation device can exchange heat with the first wedge mirror 21 and the second wedge mirror 22 inside the base 10 through the first heat exchange port 11, the first through hole 63, the second through hole 64, and the second heat exchange port 12, thereby reducing the impact of the high temperature environment on the first wedge mirror 21 and the second wedge mirror 22, ensuring the stability of the optical parameters of the first wedge mirror 21 and the second wedge mirror 22, and ensuring the accuracy of the optical path.

[0060] Exemplarily, the heat dissipation device can be an air-cooling device that provides cooling gas. The base body 10 is provided with quick-connect air pipe connectors at the first heat exchange port 11 and the second heat exchange port 12, respectively. The quick-connect air pipe connectors are bolted to the base body 10. The first heat exchange port 11 serves as an air-cooling inlet and is connected to the output end of the air-cooling device via an air pipe. The second heat exchange port 12 serves as an air-cooling hot outlet. The air-cooling device can output cold air to the first heat exchange port 11. The cold air enters the interior of the spacer 60 through the first through-hole 63, contacts the first wedge mirror 21 and the second wedge mirror 22, and is discharged to the outside of the base body 10 through the second through-hole 64 and the second heat exchange port 12, achieving efficient heat exchange.

[0061] In some embodiments, the light input tube 30 is bolted to the end of the base 10. An incident channel 31 and a reflection channel 32 are provided inside the light input tube 30, and the incident channel 31 and the reflection channel 32 are respectively connected to the accommodating cavity. The incident channel 31 is a cylindrical hole structure parallel to the incident direction, and the reflection channel 32 is a cylindrical hole structure parallel to the reflection direction. The incident channel 31 is used to receive the laser light emitted by the laser 200. The laser light can form an incident light path in the incident channel 31 and a reflected light path in the reflection channel 32.

[0062] In some embodiments, the detection component 40 is a light intensity detector, which is bolted to the light input tube 30, and the observation port of the detection component 40 is connected to the reflection channel 32 so that the laser in the reflected light path can be incident on the observation port of the detection component 40 in the reflection channel 32.

[0063] In some embodiments, the light emitting tube 50 is bolted to the end of the base 10 away from the light input tube 30. An emission channel 51 is provided inside the light emitting tube 50. The emission channel 51 is a cylindrical hole structure parallel to the emission direction. The laser light emitted from the second wedge mirror 22 can pass through the emission channel 51 to form an emission light path, and then be emitted to the galvanometer 500 and the field lens 600 through the emission channel 51.

[0064] The present application also provides a laser printing device.

[0065] The laser printing device includes a laser 200 , a power monitoring device 100 , a galvanometer 500 , and a field lens 600 . When the laser 200 emits laser light toward the power monitoring device 100 , the laser light emitted by the power monitoring device 100 enters the galvanometer 500 and the field lens 600 .

[0066] Specifically, the laser printing device also includes an optical fiber 300 and a beam expansion and collimation module 400. The laser 200, optical fiber 300, beam expansion and collimation module 400, power monitoring device 100, galvanometer 500, and field lens 600 are connected in sequence. The laser light emitted by the laser 200 is transmitted to the beam expansion and collimation module 400 via the optical fiber 300. The beam expansion and collimation module 400 converts the laser beam at the optical fiber 300 into collimated parallel light, while appropriately expanding the spot diameter to ensure that the laser light enters the power monitoring device 100 at a uniform incident angle. After passing through the power monitoring device 100, the laser light enters the galvanometer 500 and field lens 600.

[0067] This application also provides a control method. The control method can be applied to a laser printing device and executed by a control module of the laser printing device. The control module can be a control system of the laser printing device or a control component built into the power monitoring device 100.

[0068] Please also refer to Figure 6 , the control method includes the following steps.

[0069] S101. During the printing process of the laser printing device, monitoring power is obtained in real time.

[0070] The monitored power is a power value obtained by the detection component 40 performing power detection on the laser in the reflected light path.

[0071] S102: Determine whether the monitored power meets the preset abnormal condition. If yes, execute step S103; if not, end.

[0072] S103: triggering an alarm action.

[0073] The abnormal condition is used to detect whether the laser 200 has experienced power attenuation by monitoring power. The alarm action is used to remind the user to perform maintenance on the laser optical path components. The alarm action includes but is not limited to: issuing an audible and visual warning, sending an alarm message to the user's mobile device, etc.

[0074] In the example of this application, the abnormal condition is: the difference between the current monitored power and a preset reference power is greater than a preset error range, where the reference power is the monitored power during the initial laser power calibration of the laser printing device. The error range can be 5%.

[0075] In the example of this application, the laser 200 uses a laser generator with an incident power of 500W, capable of emitting 1050nm infrared laser light. The power ratio of the laser light directed to the detection component 40 to the laser light emitted from the light output tube 50 is 1:9, that is, the power ratio of the laser light in the reflected light path to the laser light in the output light path is 1:9.

[0076] During the printing process, laser light emitted by the laser 200 is transmitted through the optical fiber 300 to the beam expansion and collimation module 400. The laser then passes through the light input tube 30 and is irradiated by the first and second wedge mirrors 21 and 22, which are connected in series in opposite directions. The laser light is refracted, transmitted, and reflected by the first and second wedge mirrors 21 and 22. Ultimately, 90% of the output power enters the galvanometer mirror 500 and field lens 600 at the rear end, while 10% of the reflected power enters the detection assembly 40 for power detection. If the monitored laser power meets a preset abnormality condition, an alarm is triggered, prompting the user to perform maintenance on the laser optical path components.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A power monitoring device, characterized in that: include: A base, a light input tube, a light output tube, a wedge mirror assembly, and a detection assembly, wherein the light input tube and the light output tube are respectively connected to the two ends of the base; the wedge mirror assembly is arranged in the base and located between the light input tube and the light output tube; the detection assembly is connected to the light input tube; When the laser light enters the light-incident tube along the incident direction and passes through the wedge mirror assembly, a portion of the laser light is transmitted by the wedge mirror assembly and emitted from the light-emitting tube along the exit direction; another portion of the laser light is reflected by the wedge mirror assembly and emitted toward the detection assembly along the reflection direction; the incident direction is parallel to the exit direction, and an angle is formed between the incident direction and the exit direction; The wedge mirror assembly includes a first wedge mirror and a second wedge mirror. The first wedge mirror has a wedge angle of 0.5° and is disposed at one end of the base body close to the light entrance tube. The second wedge mirror has a wedge angle of -0.8° and is disposed at one end of the base body close to the light exit tube. The base body is provided with a spacer, and two surfaces of the spacer are respectively provided with a first groove for accommodating the first wedge mirror and a second groove for accommodating the second wedge mirror; The first wedge mirror is provided with a first pressing ring and a first washer; the first pressing ring presses the first wedge mirror away from the first groove through the first washer and is threadedly connected to the base; The second wedge mirror is provided with a second pressing ring and a second washer; the second pressing ring presses the second wedge mirror away from the second groove through the second washer and is threadedly connected to the base; A first compensation angle is formed between the two surfaces of the first gasket, and the sum of the first compensation angle and the wedge angle of the first wedge mirror is 0; and / or a second compensation angle is formed between the two surfaces of the second gasket, and the sum of the second compensation angle and the wedge angle of the second wedge mirror is 0.

2. The power monitoring device according to claim 1, wherein: The base materials of the first wedge mirror and the second wedge mirror are both silicon, and the refractive indexes of the first wedge mirror and the second wedge mirror are both 3.

5.

3. The power monitoring device according to claim 1, wherein: The first wedge mirror and the second wedge mirror both have coating layers, and the coating layers include a first layer for reducing surface reflectivity, a second layer for matching a high refractive index phase, and a third layer for matching and optimizing substrate impedance.

4. The power monitoring device according to claim 1, wherein: The power ratio of the laser directed toward the detection component to the laser emitted from the light-emitting tube is 1:

9.

5. The power monitoring device according to claim 1, wherein: The base is provided with a first heat exchange port and a second heat exchange port, and the spacer is provided with a first through hole connected to the first heat exchange port and a second through hole connected to the second heat exchange port.

6. A laser printing device, characterized in that: The device comprises a laser, a galvanometer, a field mirror and the power monitoring device according to any one of claims 1 to 5, wherein when the laser emits laser light to the power monitoring device, the laser light emitted by the power monitoring device enters the galvanometer and the field mirror.

7. A control method, characterized in that: Applied to the laser printing device according to claim 6, the control method comprises: During the printing process of the laser printing device, monitoring power is obtained in real time, wherein the monitoring power is a power value obtained by the detection component detecting the power of the reflected laser; In response to the monitored power meeting a preset abnormal condition, an alarm action is triggered.

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