Method and device for high-precision processing of optical fiber preform

Abstract

The invention provides a method and device for high-precision machining of an optical fiber preform. The method comprises the steps that machining parameters of the optical fiber preform are determined, and a grinding wheel with the corresponding size is replaced; checking whether the preform clamping plates on the two sides of the machining device are parallel to the middle grinding wheel fixing plate or not and whether the distances between the preform clamping plates on the two sides and the middle grinding wheel fixing plate are the same or not; fixing the optical fiber preform; adjusting the grinding wheel position; setting rotating speeds and advancing speeds of the grinding wheels on the two sides according to processing parameters of the optical fiber preform; grinding and polishing the processed optical fiber preform; and cleaning. According to the used device, guide grooves are longitudinally formed in the two ends of a fixed guide rail respectively, gaskets with grooves are symmetrically arranged on the inner sides of two preform clamping plates, a grinding wheel fixing plate is arranged in the middle of a fixed frame, and two grinding wheels are arranged in two grinding wheel sliding rails of the grinding wheel fixing plate respectively. The optical fiber preform does not need to be moved or rotated in the machining process, and the machining consistency and symmetry of the optical fiber preform can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optical fiber manufacturing, and particularly relates to a method and device for high-precision processing of optical fiber preforms. Background Art

[0002] The preparation technologies of various special optical fibers all include the process of processing optical fiber preforms. For example: the inner cladding of the active optical fiber used in optical fiber lasers is usually an octagonal structure, and a circular optical fiber preform needs to be processed into an octagonal structure; for the elliptical core polarization-maintaining optical fiber used in current transformers, a circular optical fiber preform needs to be processed into an asymmetric structure; for the D-shaped optical fiber used in optical fiber sensors, a circular optical fiber preform needs to be processed into a D shape.

[0003] In traditional processing methods, it is necessary to accurately position the relative position of the grinding wheel and the optical fiber preform. After one side of the optical fiber preform is processed, the optical fiber preform needs to be rotated 180 degrees, and the relative position of the grinding wheel and the optical fiber preform needs to be readjusted before the other side can be processed. It is difficult to ensure that the processing parameters such as the processing depth on both sides of the optical fiber preform are exactly the same, and it is also difficult to ensure the symmetry of the processing positions on both sides. Summary of the Invention

[0004] In view of the above problems, the present invention provides a method and device for high-precision processing of optical fiber preforms. The processing device has double-sided clamping plates and an intermediate grinding wheel fixing plate; the distance between the double-sided clamping plates and the intermediate grinding wheel fixing plate can be adjusted, but the distance always remains the same. During the processing, there is no need to move or rotate the optical fiber preform, which can effectively improve the processing consistency and symmetry of the optical fiber preform. The two grinding wheels have exactly the same size specifications and maintain the same rotation speed and traveling speed during processing, so as to ensure the consistency and symmetry of the processing accuracy of the optical fiber preform.

[0005] The present invention is completed through the following technical solutions: A method for high-precision processing of optical fiber preforms, comprising the following steps: Step 1: First, determine the processing parameters of the optical fiber preform, including: the diameter of the optical fiber preform, the grinding and polishing depth, the grinding and polishing width, the grinding and polishing shape, and the grinding and polishing position; Step 2: Replace the grinding wheel with the corresponding size according to the processing parameters; Step 3: Check whether the preform clamping plates on both sides in the processing device are parallel to the intermediate grinding wheel fixing plate, and whether the distances between the preform clamping plates on both sides and the intermediate grinding wheel fixing plate are the same; Step 4: Place one end of the optical fiber preform in the middle of the grinding wheel fixing plate, and at the same time move the preform clamping plates on both sides until the optical fiber preform is clamped. At this time, the two preform clamping plates clamp and fix the optical fiber preform; Step 5: Push the electric telescopic rod within the grinding wheel slide rail. The grinding wheel fixing frame drives the grinding wheel to move along the grinding wheel slide rail on the grinding wheel fixing plate until the grinding wheels on both sides are in close contact with the cladding of the optical fiber preform. Step 6: Set the working parameters of the grinding wheels on both sides according to the processing parameters of the optical fiber preform, including the grinding wheel rotation speed, grinding and polishing depth, radial travel speed of grinding and polishing, grinding and polishing length, and longitudinal travel speed of grinding and polishing. Step 7: Start the device to grind and polish the optical fiber preform. Step 8: After the processing is completed, remove the processed optical fiber preform and clean it.

[0006] In the above technical solution, the grinding wheel is made of emery, and the diameter of the grinding wheel is 20 - 50 mm.

[0007] In the above technical solution, the working parameters of the grinding wheel are: the rotation speed of the grinding wheel is 1800 - 2500 r / min, the grinding and polishing depth is 2 - 5 mm, the radial travel speed of grinding and polishing is 0.10 - 0.60 mm / min, the grinding and polishing length is 50 - 120 mm, and the longitudinal travel speed of grinding and polishing is 0.30 - 0.60 mm / min.

[0008] In the above technical solution, the size specifications of the two grinding wheels are exactly the same, and the same rotation speed and travel speed are maintained during processing.

[0009] A device for high-precision processing of optical fiber preforms, comprising: a base, a fixed guide rail, a preform clamping plate, a guide groove, a fixing nut, a gasket, a grinding wheel fixing plate, and a grinding wheel; on the base, two fixed guide rails and two preform clamping plates form a "well"-shaped fixing frame, and guide grooves are longitudinally arranged at both ends of the fixed guide rail. Four fixing nuts respectively pass through the preform clamping plates and are arranged in the guide grooves; gaskets with grooves are symmetrically arranged on the inner sides of the two preform clamping plates, and the grinding wheel fixing plate is arranged in the middle of the fixing frame and is parallel to the two preform clamping plates.

[0010] Furthermore, grinding wheel slide rails are respectively arranged at both ends of the grinding wheel fixing plate, electric telescopic rods are respectively arranged in each grinding wheel slide rail, grinding wheel fixing frames are respectively arranged at the ends of each electric telescopic rod, and the two grinding wheels are respectively arranged in the two grinding wheel fixing frames.

[0011] The beneficial effects of the present invention are as follows: During the processing, the optical fiber preform always remains stationary without translation or rotation. There are preform clamping plates on both sides of the processing device and a grinding wheel fixing plate in the middle. The distance between the preform clamping plates on both sides and the middle grinding wheel fixing plate can be adjusted, but the distance always remains the same. Thus, the processing grinding wheel can be accurately located on the center line of the optical fiber preform, and the symmetry of the processing can be accurately ensured. In addition, the two grinding wheels installed at both ends of the grinding wheel fixing plate have exactly the same size specifications and maintain the same rotation speed and traveling speed during processing, which can further ensure the symmetry of processing and the processing accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a schematic structural diagram of the present invention; Figure 2 is a working state diagram of the present invention; Figure 3 is a schematic diagram of drawing the optical fiber preform after processing into an elliptical core polarization maintaining fiber; Figure 4 is Figure 2 the view of plane A-A in Figure 5 is Figure 2 the view of plane B-B in

[0013] In the figure: 1 - base of the processing device, 2 - fixed guide rail, 3 - preform clamping plate, 4 - guide groove, 5 - fixing nut, 6 - gasket, 7 - grinding wheel fixing plate, 7-1 - grinding wheel track, 7-2 - electric telescopic rod, 7-3 - grinding wheel fixing frame, 8 - grinding wheel, 9 - optical fiber preform, 9-1 - preform cladding, 9-2 - preform core, 10 - processed preform, 10-1 - processed preform cladding, 10-2 - processed preform core, 11 - elliptical core polarization maintaining fiber, 11-1 - elliptical core polarization maintaining fiber cladding, 11-2 - elliptical core polarization maintaining fiber core, 12 - fixing frame. DETAILED DESCRIPTION OF THE INVENTION

[0014] As Figure 1 、 Figure 2 、 Figure 4 、 Figure 5As shown in the figure, a device for high-precision processing of optical fiber preforms, including a base 1, fixed guide rails 2, preform clamping plates 3, guide grooves 4, fixing nuts 5, gaskets 6, grinding wheel fixing plates 7, and grinding wheels 8; guide grooves 4 are longitudinally opened at both ends of the two fixed guide rails 2, and the two fixed guide rails 2 and the two preform clamping plates 3 form a "well"-shaped fixing frame 12. Four fixing nuts 5 respectively pass through the four preform clamping plates 3 and the four guide grooves 4, and the fixing frame 12 is fixed on the base 1. Grooved gaskets 6 are bonded to the inner sides of the two preform clamping plates 3, and the two gaskets 6 are symmetrical; the grinding wheel fixing plate 7 with grinding wheel tracks 7-1 at both ends is fixedly installed in the middle of the fixing frame 12. The grinding wheel fixing plate 7 is parallel to the two preform clamping plates 3. Electric telescopic rods 7-2 are respectively installed in each grinding wheel slide rail 7-1, grinding wheel fixing brackets 7-3 are installed at the ends of each electric telescopic rod 7-2, and grinding wheels 8 are installed on each grinding wheel fixing bracket 7-3.

[0015] The diameter of the optical fiber preform is 12 - 22 mm, and the diameter of the grinding wheel is 20 - 50 mm.

[0016] Specific embodiment: A method for high-precision processing of optical fiber preforms is operated according to the following steps: Taking the processing of an elliptical core polarization-maintaining optical fiber preform as an example: Step 1: Determine the processing parameters of the optical fiber preform 9, specifically including: the diameter of the cladding 9-1 of the optical fiber preform is 13.9 mm, the grinding and polishing depth is 3.6 mm, the grinding and polishing width is 4.4 mm, the grinding and polishing length is 100 mm, the grinding and polishing shape is semi-circular, and the grinding and polishing position is on both symmetrical sides of the core 9-2 of the optical fiber preform. Step 2: Replace the grinding wheel 8 with a silicon carbide grinding wheel according to the processing parameters. The outer edge of the grinding wheel 8 is semi-circular, with a width of 4.3 mm and a diameter of 25 mm. Step 3: Check whether the preform clamping plates 3 and the grinding wheel fixing plate 7 in the processing device are parallel, and whether the distances between the preform clamping plates 3 and the grinding wheel fixing plate 7 on both sides are the same. Step 4: Loosen the fixing nuts 5 at the four corners of the fixing frame 12. First, place one end of the optical fiber preform 9 in the middle of the grinding wheel fixing plate 7, hold the two preform clamping plates 3 by hand, and move inward along the guide grooves 4 at the same time until the gasket 6 clamps the optical fiber preform 9, then tighten the fixing nuts 5. At this time, the optical fiber preform 9 is fixed. Step 5: Through motor control, push the electric telescopic rod 7-2 to slide in the grinding wheel slide rail 7-1. The grinding wheel fixing bracket 7-3 installed at the end of the electric telescopic rod 7-2 drives the grinding wheel 8 to slide along the grinding wheel slide rail 7-1 on the grinding wheel fixing plate 7, and stop sliding when the grinding wheels 8 on both sides are in close contact with the cladding 9-1 of the optical fiber preform. Step 6: Control the polishing length and the longitudinal polishing speed by the up-and-down telescoping of the electric telescopic rod 7-2, and control the radial polishing speed by the left-and-right translation of the electric telescopic rod 7-2 along the grinding wheel slide rail 7-1; Set the parameters of the grinding wheel 8 according to the processing parameters in Step 1. To ensure the symmetry of the cladding 9-1 of the optical fiber preform after processing, the rotation speeds of the grinding wheels 8 on both sides are set to 1900 revolutions per minute, the radial polishing speed for controlling the polishing depth is set to 0.30 mm / min, and the longitudinal polishing speed, i.e., the up-and-down direction, is set to 0.50 mm / min; Step 7: Polish the cladding 9-1 of the optical fiber preform; Step 8: After the processing is completed, remove the processed optical fiber preform 10 and clean it.

[0017] At a high temperature of 1900 - 2100 °C, draw the processed optical fiber preform 10 to make an elliptical core polarization-maintaining fiber 11. At high temperature, under the action of surface tension, the grooves on both sides of the softened processed optical fiber preform 10 will expand outwards, and then an outward traction force will be applied to the cladding 10-1 of the processed optical fiber preform. The cross-sectional changes of the processed optical fiber preform 10 before and after drawing are as Figure 3 shown. The cladding 10-1 of the processed optical fiber preform will become circular under surface tension to form the cladding 11-1 of the elliptical core polarization-maintaining fiber, and the core 10-2 of the processed optical fiber preform will change from circular to elliptical to form the core 11-2 of the elliptical core polarization-maintaining fiber.

[0018] By changing the processing parameters in Step 1 and the size and shape of the grinding wheel 8 in Step 2, various shapes of the cladding 9-1 of the optical fiber preform can also be processed.

[0019] The present invention proposes a method for high-precision processing of optical fiber preforms. The basic principle is a fixed-type processing method for optical fiber preforms. However, the present invention is not limited to the above embodiments. For those skilled in the art of this technology, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as within the protection scope of the present invention. The content not described in detail in this specification belongs to the prior art well-known to those skilled in the art.

Claims

1. A method for high-precision processing of an optical fiber preform, characterized in that it includes the following steps: Step 1: First, determine the processing parameters of the optical fiber preform, including: the diameter of the optical fiber preform, the grinding and polishing depth, the grinding and polishing width, the grinding and polishing shape, and the grinding and polishing position; Step 2: Replace the grinding wheel (8) with corresponding dimensions according to the processing parameters; Step 3: Check whether the preform clamping plates (3) on both sides and the grinding wheel fixing plate (7) in the middle in the processing device are parallel, and whether the distances between the preform clamping plates (3) on both sides and the middle grinding wheel fixing plate (7) are the same; Step 4: Place one end of the optical fiber preform (9) in the middle of the grinding wheel fixing plate (7); at the same time, move the preform clamping plates (3) on both sides until the optical fiber preform (9) is clamped. At this time, the two preform clamping plates (3) clamp and fix the optical fiber preform (9); Step 5: Push the electric telescopic rod (7-2) in the grinding wheel slide rail (7-1), and the grinding wheel fixing frame (7-3) drives the grinding wheel (8) to move along the grinding wheel slide rail (7-1) on the grinding wheel fixing plate (7) until the grinding wheels (8) on both sides are close to the cladding (9-1) of the optical fiber preform; Step 6: According to the processing parameters of the optical fiber preform, set the working parameters of the grinding wheels (8) on both sides, including rotational speed, grinding and polishing depth, grinding and polishing radial travel speed, grinding and polishing length, and grinding and polishing longitudinal travel speed; Step 7: Start the device to grind and polish the optical fiber preform (9); Step 8: After the processing is completed, remove the processed optical fiber preform (10) for cleaning.

2. A method for high-precision processing of an optical fiber preform according to claim 1, characterized in that: the grinding wheel (8) is made of emery, and the diameter of the grinding wheel (8) is 20-50 mm.

3. A method for high-precision processing of an optical fiber preform according to claim 1, characterized in that: the working parameters of the grinding wheel (8) are: the rotational speed is 1800~2500 r / min, the grinding and polishing depth is 2~5 mm, the grinding and polishing radial travel speed is 0.10~0.60 mm / min, the grinding and polishing length is 50~120 mm, and the grinding and polishing longitudinal travel speed is 0.30~0.60 mm / min.

4. A method for high-precision processing of an optical fiber preform according to claim 1, characterized in that: the size specifications of the two grinding wheels (8) are exactly the same, and the same rotational speed and travel speed are maintained during processing.

5. A device for high-precision processing of an optical fiber preform, including: Base (1), fixed guide rails (2), preform clamping plates (3), guide grooves (4), fixing nuts (5), gaskets (6), grinding wheel fixing plates (7), grinding wheels (8); on the base (1), two of the fixed guide rails (2) and two preform clamping plates (3) form a "well"-shaped fixing frame (12), the guide grooves (4) are longitudinally arranged at both ends of the fixed guide rails (2), and the four fixing nuts (5) are respectively arranged in the four guide grooves (4) through the preform clamping plates (3); gaskets (6) with grooves are symmetrically arranged on the inner sides of the two preform clamping plates (3), and the grinding wheel fixing plate (7) is arranged in the middle of the fixing frame (12) and is parallel to the two preform clamping plates (3).

6. A device for high-precision processing of optical fiber preforms according to claim 5, characterized in that: grinding wheel slide rails (7-1) are respectively arranged at both ends of the grinding wheel fixing plate (7), electric telescopic rods (7-2) are respectively arranged in each grinding wheel slide rail (7-1), grinding wheel fixing frames (7-3) are respectively arranged at the ends of each electric telescopic rod (7-2), and the two grinding wheels (8) are respectively arranged in the two grinding wheel fixing frames (7-3).

Images