Air-cooled laser output head and device of external cladding light stripper

Abstract

The utility model provides an air-cooled laser output head and device with an external cladding light stripper. The air-cooled laser output head comprises a first tube shell, a second tube shell, an air inlet tube, an air outlet tube, an optical fiber and the cladding light stripper, the first pipe shell is connected with the second pipe shell. The air inlet pipe and the air outlet pipe are fixedly arranged on the two sides of the second pipe shell respectively. A heat dissipation base and a light-transmitting substrate are arranged in the first tube shell, a sleeve is arranged in the second tube shell, an optical output piece is arranged in the sleeve, an air cooling cavity is formed between the outer wall of the sleeve and the inner wall of the second tube shell, and an absorption cavity is formed between half-reflection and half-absorption coatings arranged on the inner wall of the sleeve in a surrounding mode. A first port of the air inlet pipe and a second port of the air outlet pipe are communicated with the air cooling cavity and the external environment; and the optical fiber is connected with the cladding light stripper and sequentially enters the first tube shell and the sleeve. According to the utility model, a high-efficiency air cooling structure, an optical fiber coating layer stripping opening rapid heat dissipation structure and a CPS external stripping cladding light structure are integrated, and forward light and return light with higher power can be borne.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of laser, concretely relates to a gas cooling laser output head and device of external cladding light stripper. BACKGROUND

[0002] The optical fiber laser is popularly applied in the fields of high-power cutting, welding and the like, and has many advantages such as compact structure, high conversion efficiency, good beam quality and easy heat dissipation.

[0003] The laser output head is a core device of the optical fiber laser and can realize flexible transmission of laser at a long distance in an application site. The common laser output head currently adopts a water cooling mode for heat dissipation, and a water cooling machine or the like is arranged to dissipate heat generated by the back-returning light in processing. This mode makes the device bulky, is not conducive to transportation and has a high cost. The laser output head adopting the gas cooling mode cannot bear several-kilowatt power output and several-hundred-watt back-returning light, so that the application of cutting or welding is limited. SUMMARY

[0004] The first object of the utility model is to provide a gas cooling laser output head of external cladding light stripper which can bear higher back-returning light power.

[0005] The second object of the utility model is to provide a laser device comprising the above-mentioned gas cooling laser output head of external cladding light stripper.

[0006] In order to realize the above-mentioned first object, the utility model provides a gas cooling laser output head of external cladding light stripper, which comprises a first tube shell, a second tube shell, an air inlet pipe, an air outlet pipe, an optical fiber and a cladding light stripper. The first tube shell is connected to the second tube shell, and the air inlet pipe and the air outlet pipe are arranged on the two sides of the second tube shell and are connected to the second tube shell. A heat dissipation base and a light-transmitting substrate are arranged in the first tube shell, a sleeve is arranged in the second tube shell, an optical output piece is arranged in the sleeve, an air cooling cavity is formed between the outer wall of the sleeve and the inner wall of the second tube shell, a semi-reflective semi-absorbing coating layer is arranged around the inner wall of the sleeve, an absorption cavity is formed between the semi-reflective semi-absorbing coating layers, the air inlet pipe comprises a first port, the air outlet pipe comprises a second port, and the first port and the second port are both connected to the air cooling cavity and the external environment. The optical fiber is connected to the cladding light stripper, the optical fiber enters the first tube shell and the sleeve in sequence, the optical fiber passes through the heat dissipation base in the interior of the first tube shell, the stripping position of the coating layer of the optical fiber is fixed in the heat dissipation base through the light-transmitting substrate, and the bare core segment of the optical fiber is connected to the optical output piece by passing through the absorption cavity in the sleeve.

[0007] Further, the optical output piece is a quartz crystal.

[0008] Further, a window piece is arranged on one side of the sleeve, and the window piece is adjacent to one end of the optical output piece away from the optical fiber.

[0009] A further option is to use a sapphire substrate as the light-transmitting substrate.

[0010] A further solution is to use a copper base for heat dissipation.

[0011] A further design includes a heat dissipation base comprising a mounting cavity and a through slot, with the mounting cavity connected to the through slot, a light-transmitting substrate disposed within the mounting cavity, and optical fibers passing through the through slot and the mounting cavity.

[0012] A further option is to use a nickel metal coating for the semi-reflective and semi-absorbent coating.

[0013] As can be seen from the above scheme, this utility model sets a semi-reflective, semi-absorbent coating inside the sleeve to form an absorption cavity, balancing the heat generated in the absorption cavity; by setting a heat dissipation base and a light-transmitting substrate, when large-angle light escapes at the stripping point, it passes through the heat dissipation base and the light-transmitting substrate with good light transmittance, and the escaped light is lost on the first tube shell; by setting an air-cooled cavity, the heat accumulated inside the sleeve is effectively dissipated, ensuring the long-term stability and reliability of the laser head performance; by using an external cladding light stripper, the reverse cladding stray light is transmitted along the optical fiber to the cladding light stripper for stripping loss cooling. This utility model achieves a lightweight laser output head, can withstand 3000W of forward light and 500W of return light. Compared with existing air-cooled laser output heads, this utility model can withstand greater forward light power and greater return light power.

[0014] To achieve the second objective mentioned above, this utility model provides a laser device, which includes: an air-cooled laser output head and a laser cooling plate as described above. The laser cooling plate is positioned relative to the cladding stripper, and the reflected light overflows from the cladding stripper and is lost on the laser cooling plate.

[0015] A further option is to use an aluminum block as the laser cooling plate.

[0016] As can be seen from the above scheme, the laser head of this utility model has an integrated high-efficiency air-cooled structure, a fiber coating stripping fast heat dissipation structure, and an external cladding stripper structure for stripping cladding light. The cladding stripper is set relative to the laser cooling plate, so that the cladding back-reflected light overflows from the cladding stripper at the tail of the laser head and is cooled by the cooling plate inside the laser housing, thereby improving the overall device's ability to resist back-reflected laser light. Attached Figure Description

[0017] Figure 1 This is a structural diagram of an embodiment of the air-cooled laser output head of the external cladding optical stripper of this utility model.

[0018] Figure 2 This is a cross-sectional view of an embodiment of the air-cooled laser output head of the external cladding optical stripper of this utility model.

[0019] Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments. Detailed Implementation

[0021] This invention relates to an external cladding stripper with an air-cooled laser output head. By incorporating an absorption cavity for absorbing reflected light and integrating a high-efficiency air-cooling structure, a rapid heat dissipation structure for the fiber coating stripping area, and a CPS external cladding stripping structure, it can withstand 3000W of forward light and 500W of reflected light. This invention also provides a laser device including the aforementioned external cladding stripper with an air-cooled laser output head.

[0022] Example of an air-cooled laser output head with an external cladding stripper:

[0023] See Figure 1 The air-cooled laser output head of the external cladding stripper in this embodiment includes: a cladding stripper (CPS) 1, an optical fiber 2, a first housing 3, a second housing 4, an air inlet pipe 5, an air outlet pipe 6, and a window 7.

[0024] The first shell 3 is connected to the second shell 4. The inlet pipe 5 and the outlet pipe 6 are respectively located on both sides of the second shell 4 and are respectively connected to the second shell 4.

[0025] The first housing 3 contains a light-transmitting substrate 31 and a heat dissipation base 32. The second housing 4 contains a sleeve 41, and the sleeve 41 contains an optical output component 411. An air-cooled cavity 901 is formed between the outer wall of the sleeve 41 and the inner wall of the second housing 4. A semi-reflective and semi-absorbent coating is arranged around the inner wall of the sleeve 41, and an absorption cavity 902 is formed between the semi-reflective and semi-absorbent coatings.

[0026] The air inlet pipe 5 includes a first port 51, and the air outlet pipe 6 includes a second port 61. Both the first port 51 and the second port 61 are connected to the air-cooled cavity 901 and the external environment, so that the externally input gas can enter the air-cooled cavity 901 from the first port 51 and then leave from the second port 61.

[0027] One end of optical fiber 2 is connected to cladding stripper 1, and the other end of optical fiber 2 sequentially enters the first housing 3 and the sleeve 41. Specifically, optical fiber 2 passes through heat dissipation base 32 into sleeve 41. In sleeve 41, optical fiber 2 passes through absorption cavity 902 and connects to optical output component 411. The stripped portion 22 of the coating layer 21 of optical fiber 2 is fixed in heat dissipation base 32 by light-transmitting substrate 31. The bare core segment 23 of optical fiber 2 passes through absorption cavity 35 and connects to optical output component 36. That is, when optical fiber 2 is located in absorption cavity 35, it does not have coating layer 21. The coating layer 21 of optical fiber 2 is stripped in heat dissipation base 32. Window 7 is provided adjacent to one side of sleeve 41, specifically adjacent to the end of optical output component 411 away from optical fiber 2.

[0028] The heat dissipation base 32 includes a mounting cavity 321 and a through groove 322, with the mounting cavity 321 communicating with the through groove 322. A light-transmitting substrate 31 is disposed within the mounting cavity 321, and the optical fiber 2 passes through the through groove 322 and the mounting cavity 321.

[0029] The light-transmitting substrate 31 is a low-absorption glass slide with low laser absorption performance, which reduces the absorption of laser energy and stabilizes its own temperature, thereby reducing the temperature at the contact point with the coating layer 21 of the optical fiber 2.

[0030] The heat dissipation base 32 is a high thermal conductivity base used to transfer heat to the first shell 3. In this embodiment, the heat dissipation base 32 is a copper base. The optical output component 36 is a quartz crystal.

[0031] By depositing a semi-reflective, semi-absorbent coating on the inner surface of the sleeve 41 to form an absorption cavity 902, the absorption of the laser within the absorption cavity 902 can be balanced, reducing the heat generated within the absorption cavity 902. The semi-reflective, semi-absorbent coating is configured to correspond to the laser wavelength; in different embodiments, different semi-reflective, semi-absorbent coatings are selected based on the wavelength of the laser. In this embodiment, for a 1080nm wavelength laser, the semi-reflective, semi-absorbent coating is a nickel metal coating. The nickel metal coating has a reflectivity of approximately 60% for 1080nm wavelength lasers, resulting in appropriate laser absorption and preventing excessive heat generation within the absorption cavity 35.

[0032] The optical output component 411 is used to output the laser light from the optical fiber 2 to the outside through the window 7. The optical output component 411 is a quartz crystal. Because the core diameter of the optical fiber 2 is relatively thin, the quartz crystal is fused to the optical fiber 2, which reduces the power density of the laser at the end face and avoids damage to the end face of the optical fiber by high-power laser light. The window 7 is a detachable window.

[0033] In practical application of this embodiment, the laser is transmitted through optical fiber 2 and output to the workpiece through window 7 by optical output component 2. Since the workpiece cannot absorb all the laser, part of the laser is reflected back to the workpiece along the original path. The reflected laser is absorbed and reflected by the semi-reflective and semi-absorbent coating at the absorption cavity 902, reducing the temperature inside the absorption cavity 902. At the same time, gas is injected from the first port 51, circulating and cooling the sleeve 41 in the gas-cooled cavity 901, and flowing out from the second port 61. The heat absorbed in the absorption cavity 902 is transferred to the outside through gas cooling, reducing the temperature inside the absorption cavity 902. The large-angle laser overflows at the stripping point 22. Through the low-absorption transparent substrate 31 and the heat dissipation base 32 with good thermal conductivity, the overflowing laser is lost on the first tube shell 3, reducing the temperature at the stripping point 22 and reducing the risk of burn-out. The more energetic reverse light is coupled into the cladding of optical fiber 2, transmitted along the cladding of optical fiber 2 to the cladding light stripper 1, and overflows at the cladding light stripper 1.

[0034] Under the conditions of room temperature 24℃ and return laser power 500W, the temperature of the stripped edge 22 of the coating layer 21 of the external cladding stripper of this embodiment can be stably maintained below 50℃. The temperature difference between the stripped edge of the coating layer 21 of the optical fiber 2 and that of the water-cooled optical fiber is less than 5℃, which can meet the requirements of 500W return laser welding and cutting applications.

[0035] Laser device examples:

[0036] The laser device in this embodiment includes a laser cooling plate and the air-cooled laser output head described in the previous embodiment. The laser cooling plate is positioned relative to the cladding stripper, so that the reflected light overflows from the cladding stripper and is lost on the laser cooling plate. The laser cooling plate is an aluminum block.

[0037] In summary, the laser head of this invention utilizes a metal layer plated on the inner wall of the sleeve to absorb the laser beam. Heat is conducted and transferred from the fiber coating at the tail end to the first tube shell for cooling. The reflected cladding light travels along the fiber to an external cladding stripper for stripping, enabling the device to withstand continuous high-power (500W) reflected light without burning out. During the high-power output process of the laser device of this invention, when reflected laser light occurs on the workpiece, the main cavity, including the heat-absorbing cavity and the air-cooling cavity, integrates a highly efficient air-cooling structure to effectively dissipate the heat accumulated in the product body and its interior, maintaining a relatively low and stable temperature and ensuring beam quality. When the fiber coating is subjected to reflected laser light, hot spots can be dissipated in time, reducing the risk of burn-out. Furthermore, the cladding stripper is externally located at the tail end of the device, attached to the heat dissipation aluminum block inside the laser housing. The reflected cladding light overflows from the cladding stripper at the tail end, improving the overall device's resistance to reflected laser light.

Claims

1. A gas-cooled laser output head for an external cladding optical stripper, characterized in that, include: First shell, second shell, inlet pipe, outlet pipe, optical fiber, and cladding stripper; The first tube shell is connected to the second tube shell, and the air inlet pipe and the air outlet pipe are respectively disposed on both sides of the second tube shell and respectively connected to the second tube shell; The first tube shell is provided with a heat dissipation base and a light-transmitting substrate. The second tube shell is provided with a sleeve, and the sleeve is provided with an optical output component. An air-cooled cavity is formed between the outer wall of the sleeve and the inner wall of the second tube shell. A semi-reflective and semi-absorbent coating is provided around the inner wall of the sleeve. An absorption cavity is formed between the semi-reflective and semi-absorbent coatings. The air inlet pipe includes a first port, and the air outlet pipe includes a second port. Both the first port and the second port are connected to the air-cooled cavity and the external environment. The optical fiber is connected to the cladding stripper. The optical fiber enters the first housing and the sleeve in sequence. The optical fiber passes through the heat dissipation base inside the first housing. The stripped portion of the coating of the optical fiber is fixed in the heat dissipation base by the light-transmitting substrate. The bare core of the optical fiber passes through the absorption cavity and is connected to the optical output component inside the sleeve.

2. The gas-cooled laser output head of the external cladding optical stripper as described in claim 1, characterized in that: The optical output component is a quartz crystal.

3. The gas-cooled laser output head of the external cladding optical stripper as described in claim 1, characterized in that: A window is also provided on one side of the sleeve, and the window is adjacent to the end of the optical output component away from the optical fiber.

4. The gas-cooled laser output head of the external cladding stripper as described in claim 1, characterized in that: The light-transmitting substrate is a sapphire substrate.

5. The gas-cooled laser output head of the external cladding optical stripper as described in claim 1, characterized in that: The heat dissipation base is a copper base.

6. The gas-cooled laser output head of the external cladding optical stripper as described in claim 1, characterized in that: The heat dissipation base includes a mounting cavity and a through groove. The mounting cavity is connected to the through groove. The light-transmitting substrate is disposed in the mounting cavity, and the optical fiber passes through the through groove and the mounting cavity.

7. The gas-cooled laser output head of the external cladding optical stripper as described in any one of claims 1 to 6, characterized in that: The semi-reflective and semi-absorbent coating is a nickel metal coating.

8. A laser device, characterized in that, include: The air-cooled laser output head and laser cooling plate as claimed in any one of claims 1 to 7, wherein the laser cooling plate is disposed relative to the cladding stripper, and the reflected light overflows and is lost on the laser cooling plate from the cladding stripper.

9. The laser device as claimed in claim 8, characterized in that, include: The laser cooling plate is an aluminum block.

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