Deep hole machining equipment for optical fiber preform

Abstract

The utility model belongs to the related field of optical fiber manufacturing technologies, and discloses optical fiber preform deep hole machining equipment which comprises a base, an electric spindle, a cutter, a supporting sleeve and a guide sleeve, and the electric spindle is provided with an axial internal channel serving as a cooling oil conveying channel; a radial through groove is annularly formed in a tool bit of the tool, and a tool bar is provided with a hollow structure and is communicated with the radial through groove and an internal channel; the supporting sleeve is coaxially mounted on the guide sleeve bracket and is provided with a cooling oil inlet; the guide sleeve is installed on the supporting sleeve, a cavity is formed between the guide sleeve and the supporting sleeve, and an oil through hole is annularly formed in the guide sleeve, communicated with the cavity and the outer wall gap of the cutter bar and communicated to the radial through groove of the cutter head. According to the utility model, the cooling process of external oil passing and internal chip removal can be realized, powder or disintegrating slag generated after grinding is prevented from directly contacting with the inner surface of a drill hole, flaws such as ring marks are reduced, structures such as a sealing guide frame (box) in the prior art are eliminated, and the arrangement space of lathe bed equipment is saved.

Description

Technical Field

[0001] The utility model belongs to the field related to optical fiber manufacturing technology, and more specifically, relates to a deep hole processing device for an optical fiber preform rod. Background Art

[0002] With the continuous advancement of fiber optic technology, an increasing number of fiber optic products require cold processing of preform rods in the early stages of production, particularly deep hole processing. Different fiber optic products require different hole sizes and distributions in the preform rods, and strict requirements are placed on the processing quality, including roughness, of the inner wall of the holes. Defects such as cracks and scratches are not tolerated.

[0003] In the prior art, the commonly used deep hole processing scheme for optical fiber preforms is to use a diamond grinding head tool installed on a high-speed electric spindle, and then clamp the optical fiber preform at the other end through two pneumatic three-jaw chucks. The diamond grinding head tool drills the optical fiber preform at a certain rotation speed and feed speed. The coolant used for grinding is injected from one end of the electric spindle at a certain pressure, flows through the inner hole of the tool to the drill bit, and then flows out through the radially distributed chip grooves, flows back along the gap between the outer wall of the tool and the workpiece, and takes away the powder or debris after the drill bit grinding. Since the main component of the optical fiber preform is quartz material, the hardness and compressive strength are very high, but its tensile strength and flexural strength are not high. It is easy to cause brittle cracks or cracks during deep hole processing. In order to avoid such defects, a higher electric spindle speed and a lower tool feed speed are usually set.

[0004] However, further research shows that the above-mentioned prior art still has the following defects or deficiencies:

[0005] First, because quartz is hard but has low tensile and flexural strength, it is very easy to produce fine debris during grinding. Common quartz rod deep-hole machining methods use oil inside the tool and chip removal outside to cool the drill bit and remove grinding powder or debris. The fine debris is discharged through the tiny gap between the tool and the inner wall of the workpiece drill hole. If the debris is large or there is significant runout when the drill rod rotates, irregular ring marks, or bamboo knot marks, may appear on the inner wall of the drill hole, affecting the quality of the inner wall. Severe ring marks can affect the quality of the fiber drawing process in the later process, affecting its mechanical strength and geometric symmetry.

[0006] Secondly, the internal oil flow and external chip removal system requires a dedicated guide frame (box) to seal and collect the return cooling oil. Because the return cooling oil contains a significant amount of grinding dust carried away after drilling, the guide frame (box) can easily become fouled or clogged after long-term operation, affecting the cooling oil's efficient circulation. Furthermore, fine powder or debris can easily enter the gap between the drill pipe guide sleeve and the cutter bar, wearing away the finish of the mating surface and compromising its support effectiveness. In severe cases, this can cause unstable drill pipe rotation and increased runout, compromising drilling quality.

[0007] Finally, the currently commonly used method for clamping optical fiber preforms is a pneumatic three-jaw chuck, in which nylon and other plastics are used as buffer pads between the jaws and the preform to prevent the quartz rod from breaking during clamping. In order to ensure stable clamping, nylon and other plastic pads need to be customized according to the size of the preform, and need to be fine-tuned after installation to ensure the alignment of the workpiece. Therefore, the workpieces for deep hole processing are usually of fixed size to ensure the repeatability and stability of deep hole processing. For different optical fiber products, the outer diameters of optical fiber preforms often vary. Before drilling, the pad size or structure needs to be replaced to meet the clamping requirements of quartz rods of different sizes. In order to ensure the parallelism and alignment of the clamping, the installation accuracy of the clamping pads needs to be recalibrated and debugged. This process is often cumbersome and consumes a lot of debugging and verification time. Utility Model Content

[0008] In response to one or more of the above-mentioned defects or improvement needs of the prior art, the utility model provides a deep-hole processing equipment for optical fiber preform rods, which makes targeted improvements to the specific structures and settings of multiple components such as guide sleeves, support sleeves, tools and / or pneumatic parallel grippers, and can realize the cooling process of external oil and internal chip removal in a compact and easy-to-control manner, effectively avoiding the direct contact of powder or debris generated after grinding with the inner surface of the workpiece drill hole, reducing the occurrence of defects such as ring marks, and at the same time, the sealing guide frame (box) and other structures in the prior art can be eliminated, significantly saving the layout space of the bed equipment; in addition, it can also realize the clamping of workpieces of different outer diameters, avoid frequent switching of clamping pads, and further improve the repeat positioning accuracy.

[0009] To achieve the above-mentioned object, the present invention provides a deep hole processing device for an optical fiber preform, which is characterized by comprising a base, an electric spindle, a tool, a support sleeve and a guide sleeve, wherein:

[0010] The electric spindle is mounted on the base and can perform axial movement and uniform rotation, and has an axial internal channel used as a cooling oil delivery channel;

[0011] The tool is mounted on the front end of the electric spindle and rotates with it. Its cutter head is circumferentially provided with a plurality of radial through slots. The tool rod has a hollow structure and is connected to the plurality of radial through slots of the cutter head and the internal channel of the electric spindle.

[0012] The support sleeve is coaxially mounted on the guide sleeve bracket and is provided with a first cooling oil inlet;

[0013] The guide sleeve is coaxially mounted on the support sleeve and forms a chamber A therebetween. The chamber A is connected to the first cooling oil inlet for buffering and merging the cooling oil. A plurality of first oil holes are circumferentially opened on the guide sleeve. These first oil holes connect the chamber A with the outer wall gap of the tool rod and then connect to the plurality of radial grooves of the tool head, thereby forming a main oil circuit structure.

[0014] As a further preferred embodiment of the present invention, a second cooling oil inlet is provided on the support sleeve, and the support sleeve cooperates with the guide sleeve to form a chamber B therebetween, and the chamber B is communicated with the second cooling oil inlet for buffering and merging cooling oil;

[0015] A plurality of second oil holes are circumferentially opened on the guide sleeve, and a plurality of oil storage grooves are opened on the inner wall of the guide sleeve. The second oil holes connect the chamber B with the oil storage grooves, and are used to transport a portion of the cooling oil to the tool rod to provide lubrication support and oil seal, thereby forming a secondary oil circuit structure.

[0016] As a further preference of the present invention, the support sleeve is an axially hollow cup-shaped structure, and the first cooling oil inlet and the second cooling oil inlet are respectively opened at the cup body position and the cup mouth position of the cup-shaped structure, serving as the inlets of the main oil circuit structure and the auxiliary oil circuit structure.

[0017] As a further preferred embodiment of the present invention, the guide sleeve is an annular structure with a through hole inside, and a plurality of annular grooves are provided on its outer side for installing a sealing ring.

[0018] As a further preferred embodiment of the present invention, the deep hole processing equipment further comprises a plug and a cylinder, wherein one end of the plug is used to wrap the preform workpiece, and the other end of the plug is in conflict with the telescopic rod of the cylinder.

[0019] As a further preferred embodiment of the present invention, the deep hole processing equipment further includes a pneumatic parallel gripper, which is provided on both sides of the preform workpiece for clamping the workpiece.

[0020] As a further preferred embodiment of the present invention, each of the pneumatic parallel grippers is equipped with a V-shaped clamping pad for clamping workpieces of different sizes.

[0021] As a further preferred embodiment of the present invention, the V-shaped clamping pad is made of hard plastic material, and its V-shaped groove is designed to have an angle of 90°.

[0022] As a further preferred embodiment of the present invention, the tool is installed on the front end of the electric spindle using a expansion sleeve.

[0023] As a further preferred embodiment of the present invention, the tool is equipped with a tool bar support and a tool bar bracket for auxiliary support.

[0024] In general, the above technical solutions conceived by the present invention have the following technical advantages compared with the existing technology:

[0025] (1) The present invention makes targeted improvements to the specific structures and settings of the guide sleeve, support sleeve, tool and other components, and is able to reset the coolant flow mode, changing it to external oil flow and internal chip removal, so that the powder or debris generated after grinding does not pass through the outer wall of the drill rod, does not contact the surface of the inner hole of the workpiece, and flows directly from the tool tube. This can reduce the impact of drilling chip removal on the surface quality of the inner hole of the workpiece, will not cause any secondary scratches, avoid the generation of defects such as inner wall ring marks, and ensure the processing quality of the inner wall of the drill hole;

[0026] (2) Since the flow direction of the coolant is changed, the guide frame (box) originally used to collect powder or debris can be eliminated, thus avoiding the occurrence of fouling or blockage in the entire oil circulation circuit; and since the cooling return oil flows directly from the drill rod head along the inner hole, the powder or debris generated by grinding will not pass through the drill rod guide sleeve, thus avoiding the wear of the inner hole wall of the guide sleeve or the outer wall of the tool rod, thereby improving the rotation stability of the tool and the service life of the guide sleeve;

[0027] (3) The present invention further optimizes the design of the guide sleeve so that the coolant can be smoothly and sealedly pressed along the outer wall of the tool rod to the drill grinding area with stable pressure, thereby ensuring the cooling effect during grinding; the design of the through groove and oil storage groove in the guide sleeve can form an oil tank with a certain pressure, providing lubrication support and oil seal for the tool rod, ensuring the stability of the tool rod's high-speed rotation, and the oil seal prevents the leakage of the main cooling oil, thereby improving the sealing of the cooling oil circulation circuit;

[0028] (4) The present invention changes the conventional pneumatic three-jaw chuck clamping mode to a pneumatic parallel gripper and adopts a V-shaped clamping block design to achieve stable clamping of workpieces of different sizes. In addition, when drilling preforms of different sizes, the switching and installation work of the clamping components can be reduced, and the calibration and debugging work of the installation and positioning accuracy of key components can be reduced, thereby ensuring the stability of the equipment and improving production efficiency.

[0029] (5) The deep hole processing equipment of the present invention has a compact overall structure and is easy to operate. Compared with existing products, it helps to improve the performance quality of the processed optical fiber preform rods, and thus has good practical value and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the deep hole processing equipment provided in this application;

[0031] Figure 2 It is a schematic diagram for exemplarily showing the assembly of the expansion sleeve in this application;

[0032] Figure 3 This is a structural cross-sectional view of the guide sleeve, the support sleeve, and part of the conveying channel according to a preferred embodiment of the present application;

[0033] Figure 4 It is a cross-sectional view used to more specifically show the structure of the support sleeve;

[0034] Figure 5 It is a cross-sectional view used to more specifically show the structure of the guide sleeve;

[0035] Figure 6 It is a schematic diagram for exemplarily showing the assembly of the support sleeve and the guide sleeve in this application;

[0036] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0037] 1-base; 1-long guide rail; 3-short guide rail; 4-mounting slide; 5-electric spindle; 6-fixed support; 7-tool; 7.1-tool bar; 7.2-tool head; 7.3-radial slot; 8-tool bar support; 9-tool bar bracket; 10-guide sleeve support; 11-workpiece clamping support; 12-guide sleeve bracket; 13-support sleeve; 13.1-first cooling oil inlet; 13.2-chamber A; 13.3-second Cooling oil inlet; 13.4- Chamber B; 14- Guide sleeve; 14.1- First oil hole; 14.2- Oil storage groove; 14.3- Second oil hole; 15- Pneumatic parallel gripper; 16- V-type clamping pad; 17- Preform workpiece; 18- Plug; 19- Cylinder; 20- Expansion sleeve; 21.1- O-ring; 21.2- O-ring; 21.3- O-ring; 22- Guide rail fixture. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solutions and advantages of this application more clearly understood, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0039] It should be understood that expressions such as "include" and "may include" used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as "include" and / or "have" may be interpreted as indicating a specific characteristic, number, operation, constituent element, component, or combination thereof, but may not be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0040] It should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0041] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. Throughout the description of this application, "plurality" means two or more, unless otherwise specifically defined.

[0042] In this application, unless otherwise specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they can refer to fixed connection, detachable connection, or integral connection; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0043] Figure 1 This is a schematic diagram of the overall structure of the deep hole processing equipment provided by this application. Figure 1 To explain this application in more detail.

[0044] like Figure 1 As shown, the deep hole processing equipment provided by the present application mainly includes components such as a base 1, an electric spindle 5, a tool 7, a support sleeve 13 and a guide sleeve 14, which will be explained in detail one by one below.

[0045] See Figure 1, the base 1 serves as the main body of the device, and is used to support and carry all working parts, and ensure that the equipment is stable and vibration-free. Specifically, the base 1 can be divided into two parts, left and right, according to the functional areas. The left part is the area where the drill rod tool and the electric spindle move axially, and the right part is the area where the clamping parts, including the workpiece, move laterally according to the position requirements of the punching section. The left and right sides of the base 1 are respectively equipped with long guide rails 2 and short guide rails 3, each for ensuring the parallelism of movement, and each moving part moves stably on the parallel guide rails by installing a slider 4. The fixed support 6 of the electric spindle 5 and the lower part of the workpiece clamping support 11 are equipped with a screw and a drive motor (not shown in the figure), which can be controlled by the program to perform precise position movement in the specified direction.

[0046] The electric spindle 5 is mounted on the base 1 and can move axially and rotate at a constant speed. It also has an internal axial channel for cooling oil. A tool 7 is mounted on the front end of the electric spindle 5 and rotates with it. Its cutter head 7.2 is circumferentially defined by multiple radial slots 7.3. The tool shank 7.1 is hollow and connects to the multiple radial slots 7.3 of the cutter head 7.2 and the internal channel of the electric spindle 5.

[0047] More specifically, the electric spindle 5 can rotate stably and uniformly under program control, with a maximum speed of up to 12,000 r / min. It is installed in the fixed support 6 and can move axially along with the fixed support 6. The electric spindle 5 can be designed with an internal channel, such as a deep hole structure, along the axial direction to serve as a delivery channel for cooling oil. The tool 7 can adopt a conventional tool for quartz drilling. For example, the tool rod 7.1 is a hollow steel pipe with an inner hole, and the head is processed with an internal thread for installing a positioning drilling cutter head. The front end and outer side of the tool head 7.2 are made of high-hardness diamond material, and then a plurality of (usually four) through grooves are opened in the circumferential direction to realize the circulation of cooling oil outside and inside the tool tube. In addition, the tool head 7.2 can be installed on the tool rod 7.1 through an external thread connection, which is convenient for replacement after wear in the later stage.

[0048] According to a preferred embodiment of the present application, the tool 7 can be mounted on the front end of the electric spindle 5 via a clamping sleeve 20, and the friction transmission of the clamping sleeve 20 enables the tool 7 to rotate at a uniform and stable speed. The machining accuracy of the clamping sleeve 20, including concentricity, coaxiality, and smoothness, must be very high to ensure the positioning accuracy of the tool 7 after installation. In addition, the tool 7 is equipped with a tool bar support 8 and a tool bar bracket 9 for auxiliary support. A support bearing and nylon washer are installed in the middle to support and cushion the high-speed rotation of the tool bar and the vibration caused by rotation, thereby improving the stability of the tool 7 during operation. The number of drill bar brackets can be reasonably arranged according to the length of the drill bar or the drilling depth.

[0049] More specifically, the guide sleeve support 10 is mounted on the far right side of the long guide rail 2, adjacent to the workpiece clamping support 11. A slider 4 is mounted at its bottom, which can move on the long guide rail 2, and a guide sleeve bracket 12 is mounted on it. The support sleeve 13 is coaxial with the tool bar and mounted on the guide sleeve bracket 12, and is provided with a first cooling oil inlet 13.1; the guide sleeve 14 is coaxially mounted on the support sleeve 13 and forms a chamber A therebetween, which is connected to the first cooling oil inlet 13.1 for buffering and merging cooling oil; in addition, the guide sleeve 14 is also circumferentially provided with a plurality of first oil holes 14.1, which connect the chamber A 13.2 with the outer wall gap of the tool bar 7.1, and then connect to the plurality of radial through grooves 7.3 of the cutter head 7.2. The above together constitute the main oil circuit structure in this application.

[0050] Since the coolant flow direction has been changed and external oil flow and internal chip removal are adopted, there is no need to set up a large guide frame (box) to collect the cooling oil and powder generated by grinding. The support sleeve 13 is installed on the guide sleeve bracket 12, and the guide sleeve 14 is installed on the support sleeve 13. The axial center lines of all its components need to be consistent with the axial center lines of the electric spindle and the tool to ensure the processing accuracy of the drilling equipment. Since the guide sleeve 14 needs to support the stable rotation of the tool 7 and is very prone to wear, its material can preferably use copper material with excellent wear resistance to avoid scratching the surface of the tool rod 7.1. The guide sleeve 14 and the tool rod 7.1 require a very smooth clearance fit. The clearance cannot be too large or too small to ensure the rotation stability of the tool 7. Therefore, a new guide sleeve 14 needs to be replaced regularly.

[0051] Specific reference Figure 3 When the cooling oil circulation needs to be started, the cooling oil can be pressed into the main oil circuit structure inlet of the support sleeve 13, that is, the first cooling oil inlet 13.1, through the oil pump, and then enter the chamber A13.2 formed between the support sleeve 13 and the guide sleeve 14 for pressure and flow stabilization. The O-rings 21.1 and 21.2 are used to seal and prevent the cooling oil from leaking out; then the cooling oil flows through the multiple first oil holes 14.1 arranged circumferentially (for example, in an oblique direction) to the gap on the outer wall of the tool shank 7.1 of the tool 7, and then continues along the outer wall gap of the tool shank 7.1 through the radial through groove 7.3 circumferentially opened on the cutter head 7.2 to flow into the hollow structure of the tool shank 7.1. In the above main oil circuit structure, the connection between the guide sleeve 14 and the workpiece 17 can be sealed by the O-ring 21.3.

[0052] Based on the above design, in this solution, cooling oil is pressed out of the oil tank, drained through a guide sleeve, and pressed into the grinding area of ​​the drill head from the outer wall of the tool bar. Then, through the uniformly distributed circumferential grooves, the powder generated by grinding is returned from the inner hole of the tool bar. Finally, the cooling return oil flows out of one end of the electric spindle, reaching the filter device and the oil tank, ultimately completing the cooling oil circulation process. Compared with the existing technology, this oil supply and cooling method with external oil flow and internal chip removal can effectively prevent the powder or debris generated after grinding from directly contacting the inner surface of the workpiece drill hole, reducing the occurrence of defects such as ring marks. Because grinding powder or debris no longer enters the guide frame (box) and does not flow into the gap between the tool bar and the guide sleeve, wear on the guide sleeve and tool bar is avoided, ensuring the stability of the tool bar's high-speed rotation, improving the service life of the tool and guide sleeve, and ensuring the drilling quality of deep hole machining. In addition, the elimination of the guide frame (box) saves space for the bed equipment layout and avoids powder fouling or clogging.

[0053] See Figure 3 and Figure 5 According to a preferred embodiment of the present application, the guide sleeve 14 is further provided with a plurality of second oil holes 14.3 (for example, three) in a vertical shape in an annular shape, and a plurality of oil storage grooves 14.2 are machined on the inner wall of the guide sleeve 14; the second oil holes 14.3 connect the chamber B13.4 with the oil storage grooves 14.2, and are used to transport a portion of the cooling oil to the tool rod 7.1 to provide lubrication support and oil seal, thereby forming a secondary oil circuit structure.

[0054] Based on the above concept, in this solution, the cooling oil enters the chamber B13.4 formed between the support sleeve 13 and the guide sleeve 14 through the inlet of the secondary oil circuit structure, that is, the second cooling oil inlet 13.3, and then flows to the inner wall of the guide sleeve 14 through the above-mentioned second oil hole 14.3. The cooling oil will form an oil groove with a certain pressure at the oil storage groove 14.2, providing lubrication support and oil sealing for the tool rod, ensuring the stability of the high-speed rotation of the tool rod and the sealing of the coolant circuit.

[0055] According to a preferred embodiment of the present application, the deep hole processing equipment further includes a pneumatic parallel gripper 15 , which is provided on both sides of the workpiece 17 to be processed for clamping the workpiece.

[0056] According to a preferred embodiment of the present application, each of the pneumatic parallel grippers 15 is equipped with a V-shaped clamping pad 16 for clamping workpieces of different sizes. In addition, the V-shaped clamping pad 16 is made of hard plastic material, and its V-shaped groove is designed to have a 90° opening angle.

[0057] More specifically, the clamping support 11 is installed on the right part of the base 1, and the slider 4 is installed below and can move laterally along the short guide rail 3. Two pneumatic parallel grippers 15 for clamping the workpiece are installed on the upper part, and the two parallel grippers are driven by compressed air to achieve synchronous clamping or release. The pneumatic parallel gripper 15 is provided with symmetrical V-shaped clamping pads 16 at the clamping position to clamp the preform workpiece 17. Similarly, the clamping center of the two pairs of V-shaped clamping pads 16 and the central axis connected to them need to be consistent with the rotation center axis of the electric spindle 5 and the tool 7 to ensure processing parallelism and alignment. The V-groove of the V-shaped clamping block 16 is preferably designed to have a 90° opening angle, which can clamp workpieces 17 of different outer diameters within a certain range, ensure that the center of the workpiece is always in a constant spatial position, and ensure high clamping accuracy and clamping stability.

[0058] The above design utilizes a pneumatic parallel gripper design for clamping the optical fiber preform, which utilizes a V-shaped clamping block. This design ensures excellent clamping positioning accuracy and repeatability while enabling the clamping of workpieces of varying outer diameters. This eliminates the need for frequent switching of clamping blocks and reduces the installation and commissioning of key positioning components. Furthermore, the V-shaped clamping block is constructed of hard plastic, protecting the quartz workpiece from fracturing while ensuring stability and repeatable positioning accuracy.

[0059] According to another preferred embodiment of the present application, the above-mentioned deep hole processing equipment also includes a plug 18 and a cylinder 19. One end of the plug 18 is provided with an inner hole of a certain depth and has a step design, which is used to wrap the preform rod workpiece 17. The other end thereof is in contact with the telescopic rod of the cylinder 19 and is pushed by the cylinder 19.

[0060] Through the above design, on the one hand, it can support the workpiece 17 in the axial direction during drilling, because the electric spindle 5 and the tool 7 will feed in the axial direction during drilling, which will generate a small axial pushing force on the workpiece 17. With the support of the plug 18, the workpiece 17 can be prevented from axial movement, thereby improving the stability of the workpiece clamping; on the other hand, due to the deep hole processing of the preform rod, some holes need to be drilled through the quartz rod at the last moment, and the glass will often shatter, the coolant will spray out, etc. at the moment when the tool finally drills through, which will cause certain safety and quality risks. The inner hole step design of the plug 18 can prevent these phenomena from occurring.

[0061] The working process of the drilling processing equipment according to the present application will be described in detail below.

[0062] After installing the tool 7, tool bar bracket 9, guide sleeve bracket 12, supporting sleeve 13 and guide sleeve 14, as well as the pneumatic parallel gripper 15 and its V-shaped clamping pad 16, the entire assembly needs to be calibrated for alignment and runout to ensure that all central axes are parallel and coaxial. Only after these commissioning and calibration steps are completed and the equipment has achieved a high level of alignment accuracy can normal drilling operations begin.

[0063] When drilling begins, first move the guide sleeve support 10 so that the guide sleeve 14 is in close contact with the front end of the preform workpiece 17. The O-ring 21.3 arranged in the groove on the outer side of the guide sleeve 14 ensures the sealing of the entire area. After the position of the guide sleeve support 10 is determined, the guide rail clamp 22 is locked to ensure that the guide sleeve 14 will not move during workpiece processing, thereby ensuring the sealing of the system.

[0064] The coolant circulation system is then activated. Coolant is pumped into the main oil circuit inlet of the support sleeve 13 via an oil pump. It then enters chamber A13.2 formed between the support sleeve 13 and the guide sleeve 14, where it maintains a constant pressure and flow. O-rings 21.1 and 21.2 are installed at both ends of chamber A13.2 to prevent leakage. The coolant then flows through a plurality of circumferentially arranged first oil holes 14.1 (six diagonally arranged oil holes are shown in the figure) to the front end of the preform 17. The coolant then flows along the outer wall gap of the cutter bar 7.1 and into the hollow structure of the cutter bar 7.1 through radial slots 7.3 uniformly arranged circumferentially in the cutter head 7.2. As the electric spindle 5 drives the tool rod 7.1 and the tool head 7.2 to rotate at high speed, the diamond-grinded tool head 7.2 continuously grinds the quartz preform rod, so that a deep hole consistent with the drill bit size is machined in the axial direction of the preform rod workpiece 17. Cooling oil continuously flows through the tool 7 and the grinding part inside the preform rod workpiece 17, taking away the heat generated by grinding, and also taking away the powder or debris generated.

[0065] In addition, a portion of coolant enters as a secondary oil circuit through the secondary oil circuit structural interface on the support sleeve 13, also known as the second cooling oil inlet 13.3. It then enters the chamber B13.4 formed between the support sleeve 13 and the guide sleeve 14. After undergoing pressure and flow stabilization, it enters through the circumferentially distributed second oil holes 14.3 on the guide sleeve 14, ultimately reaching evenly spaced (three shown in the figure) oil reservoirs 14.2. The cooling oil builds up a certain oil pressure within these reservoirs, providing lubrication support for the rotation of the tool bar 7.1 and improving its stability during high-speed rotation. These reservoirs also form circumferential oil seals, preventing leakage of the primary cooling oil and improving the sealing of the coolant circulation system. Finally, the electric spindle 5 and the motor drive can be activated through program control, causing the tool 7 to drill the preform workpiece 17 at a specific rotational speed and feed rate.

[0066] In summary, the solution provided by the present application uses the method of external oil flow and internal chip removal, so that the powder or debris generated by the grinding process does not pass through the guide sleeve and the tool rod, nor does it pass through the inner hole wall of the workpiece, thereby reducing mechanical wear, improving processing quality and stability, and also increasing the service life of vulnerable parts. Since the coolant flows outside and the chips are removed inside, the powder generated by the drill grinding flows directly from the tool tube and does not pass through the outside of the tube. Therefore, the originally large closed guide frame (box) is no longer needed to recover the coolant and remove chips, thus avoiding the problems of fouling and clogging. The powder generated by grinding eventually flows back to the oil tank through the inner hole of the tool rod and the electric spindle, and is deposited in the designated position after being filtered.

[0067] It is easy for those skilled in the art to understand that the above is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A deep hole processing device for optical fiber preform, characterized in that: It comprises a base (1), an electric spindle (5), a tool (7), a support sleeve (13) and a guide sleeve (14), wherein: The electric spindle (5) is mounted on the base (1) and can perform axial movement and uniform rotation, and has an axial internal channel used as a cooling oil delivery channel; The tool (7) is mounted on the front end of the electric spindle (5) and rotates therewith; a plurality of radial through slots (7.3) are formed in a circumferential direction on the tool head (7.2); and a tool rod (7.1) has a hollow structure and is connected to the plurality of radial through slots (7.3) of the tool head (7.2) and the internal channel of the electric spindle (5); The support sleeve (13) is coaxially mounted on the guide sleeve bracket (12) and is provided with a first cooling oil inlet (13.1); The guide sleeve (14) is coaxially mounted on the support sleeve (13) and a chamber A (13.2) is formed between the two. The chamber A (13.2) is connected to the first cooling oil inlet (13.1) for buffering and merging cooling oil. A plurality of first oil holes (14.1) are circumferentially formed on the guide sleeve (14). These first oil holes (14.1) connect the chamber A (13.2) with the outer wall gap of the tool rod (7.1) and then connect to the plurality of radial grooves (7.3) of the tool head (7.2), thereby forming a main oil circuit structure.

2. The deep hole processing equipment according to claim 1, characterized in that The support sleeve (13) is provided with a second cooling oil inlet (13.3), the support sleeve (13) cooperates with the guide sleeve (14) to form a chamber B (13.4) therebetween, and the chamber B (13.4) is communicated with the second cooling oil inlet (13.3) for buffering and merging cooling oil; The guide sleeve (14) is provided with a plurality of second oil holes (14.3) in an annular direction, and the inner wall of the guide sleeve (14) is provided with a plurality of oil storage grooves (14.2). The second oil holes (14.3) connect the chamber B (13.4) with the oil storage grooves (14.2) and are used to transport a portion of cooling oil to the tool rod (7.1) to provide lubrication support and oil seal, thereby forming a secondary oil circuit structure.

3. The deep hole processing equipment according to claim 2, characterized in that The support sleeve (13) is an axially hollow cup-shaped structure, and the first cooling oil inlet (13.1) and the second cooling oil inlet (13.3) are respectively opened at the cup body position and the cup mouth position of the cup-shaped structure, serving as the inlets of the main oil circuit structure and the auxiliary oil circuit structure.

4. The deep hole processing equipment according to claim 2, characterized in that The guide sleeve (14) is an annular structure with a through hole inside, and a plurality of annular grooves are provided on its outside for installing sealing rings.

5. The deep hole processing equipment according to any one of claims 1 to 4, characterized in that: The deep hole processing equipment further comprises a plug (18) and a cylinder (19), wherein one end of the plug (18) is used to wrap the preform workpiece (17), and the other end of the plug (18) is in conflict with the telescopic rod of the cylinder (19).

6. The deep hole processing equipment according to claim 5, characterized in that The deep hole processing equipment further comprises pneumatic parallel grippers (15), which are arranged on both sides of the preform workpiece (17) and are used for clamping the workpiece.

7. The deep hole processing equipment according to claim 6, characterized in that The pneumatic parallel grippers (15) are each equipped with a V-shaped clamping pad (16) for clamping workpieces of different sizes.

8. The deep hole processing equipment according to claim 7, characterized in that: The V-shaped clamping pad (16) is made of hard plastic material, and its V-shaped groove is designed to have an opening angle of 90 degrees.

9. The deep hole processing equipment according to any one of claims 1 to 4, characterized in that: The tool (7) is mounted on the front end of the electric spindle (5) using a tightening sleeve (20).

10. The deep hole processing equipment according to claim 9, characterized in that: The tool (7) is equipped with a tool bar support (8) and a tool bar bracket (9) for auxiliary support.

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