A positioning tool and machining system

Abstract

The utility model discloses a positioning frock and processing system, include: base structure is provided with workpiece locating surface, workpiece locating surface has workpiece locating center, clamping structure includes drive assembly, a plurality of dog and a plurality of linear moving assembly, linear moving assembly is connected with dog, each linear moving assembly is evenly spaced apart and is arranged on base structure along the circumference, drive assembly is suitable for driving each linear moving assembly and dog and moves in the direction of pointing to or away from workpiece locating center synchronously. The utility model each linear moving assembly evenly distributes along the circumference and moves synchronously and points to or away from workpiece locating center, has guaranteed that the clamping center of dog to ceramic screw element is consistent with the locating center of workpiece locating surface, has effectively solved the problem of inaccurate repeated positioning in traditional method. Because synchronous movement's dog can accurate alignment locating center, has reduced the time of needing through the watch repeatedly correction after traditional clamping greatly, has promoted the processing efficiency.

Description

Technical Field

[0001] This utility model relates to the field of tooling and fixture technology, specifically to a positioning tooling and processing system. Background Technology

[0002] With the advancement of battery materials and the increasing demands for safety and energy density, traditional steel screw pumps can no longer meet the needs of equipment requiring high wear resistance. Therefore, ceramic screw pumps have emerged. Ceramic materials possess extremely high hardness, second only to diamond. The irregular structures of ceramic threaded components, such as inner and outer circles, arcs, and splines, make them extremely difficult to manufacture.

[0003] When positioning ceramic threaded components, the component is placed on the workpiece's positioning surface and then clamped using a fixture. However, due to the irregular structure of the ceramic threaded component, clamping it is cumbersome and complex. Furthermore, current tooling is inaccurate when repeatedly positioning ceramic threaded components, requiring lengthy calibration with a dial indicator. Utility Model Content

[0004] In view of this, the present invention provides a positioning fixture and processing system to solve the problems of inaccurate positioning of ceramic threaded components by current fixtures and long calibration time of dial indicator.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] In a first aspect, this utility model provides a positioning fixture, comprising:

[0007] A base structure, wherein a workpiece positioning surface is provided on the base structure, and the workpiece positioning surface has a workpiece positioning center;

[0008] The clamping structure includes a drive assembly, multiple jaws, and multiple linear moving assemblies. The linear moving assemblies are connected to the jaws. Each of the linear moving assemblies is evenly spaced along the circumference on the base structure. The drive assembly is adapted to drive each linear moving assembly and the jaws to move synchronously in a direction pointing towards or away from the workpiece positioning center.

[0009] The advantages of the above positioning fixture are: by setting multiple linear moving components and jaws evenly spaced along the circumference, and cooperating with the drive component to achieve synchronous movement, it can provide uniform and symmetrical clamping force for the irregular structure of ceramic threaded components, avoiding the cumbersome adjustment steps caused by the irregular structure in the traditional clamping method.

[0010] Each linear moving component is evenly distributed along the circumference and moves synchronously toward or away from the workpiece positioning center, ensuring that the clamping center of the chuck on the ceramic threaded element is consistent with the positioning center of the workpiece positioning surface, effectively solving the problem of inaccurate repetitive positioning in traditional methods.

[0011] Because the synchronously moving jaws can accurately align with the positioning center, the time required for repeated calibration using a dial indicator after traditional clamping is greatly reduced, thus improving processing efficiency.

[0012] The positioning fixture of this invention is simple to operate, has high work efficiency, and can process internal splines of ceramic threaded components in large quantities.

[0013] The positioning fixture of this invention has a simple workpiece clamping process, accurate positioning, high production efficiency, and cost savings.

[0014] The technical solution is further optimized, and the base structure includes:

[0015] The base has a mandrel limiting hole.

[0016] The mandrel is positioned within the mandrel limiting hole and extends upward from the base, with the top surface of the mandrel serving as the workpiece positioning surface.

[0017] The technical solution is further optimized, and the driving component includes:

[0018] A turntable, which is rotatably mounted on a spindle extending upward from the base;

[0019] Multiple links, one end of each link is hinged to a turntable, and the other end of each link is hinged to a linear motion component;

[0020] The first pendulum arm is connected to the side wall of the turntable. When an external force is applied to the first pendulum arm, the first pendulum arm drives the turntable to rotate.

[0021] The beneficial effects of the above technical solution are as follows: By using the design of driving the turntable to rotate through the first swing arm, the rotational driving force is concentrated on a single swing arm. The operator only needs to apply a small external force to the first swing arm to complete the synchronous opening and closing of multiple jaws. Compared with the cumbersome operation of adjusting multiple jaws separately in the traditional method, this significantly reduces the difficulty of clamping and shortens the clamping time.

[0022] To further optimize the technical solution, the driving component is located below the chuck, and there is an accommodating space between the driving component and the chuck. A locking structure suitable for locking and positioning the driving component is provided in the accommodating space.

[0023] The beneficial effects of the above technical solution are as follows: the locking structure can rigidly lock the position of the drive component after the chuck moves to the target position through the drive component, thereby locking the chuck and avoiding accidental sliding or displacement of the chuck due to external interference such as equipment vibration and cutting force impact during the processing. It can effectively solve the problem of reduced positioning accuracy caused by loose clamping during the processing of ceramic threaded components.

[0024] The technical solution is further optimized by providing external threads on the outer wall surface of the mandrel extending upward from the base;

[0025] The locking structure includes a locking disc and a second rocker arm; the locking disc is annular, and an internal thread is provided on the inner ring wall of the locking disc, and the locking disc is threadedly assembled on the spindle; the second rocker arm is connected to the locking disc, and when an external force is applied to the second rocker arm, the second rocker arm drives the locking disc to rotate and rise along the spindle, and when the locking disc contacts the top wall of the drive assembly, the locking disc locks the drive assembly.

[0026] To further optimize the technical solution, the mandrel is divided into a first column, a second column, and a third column that are coaxially connected. The first column is set in the mandrel limiting hole, and the diameter of the second column is larger than that of the first column and the third column, respectively. The second column is connected to the base by fasteners, and the external thread is set on the outer wall surface of the third column.

[0027] To further optimize the technical solution, a chip removal channel is provided through the mandrel; after the clamping structure positions the workpiece, the inner cylinder of the workpiece corresponds to the chip removal channel, so that the waste chips after processing the inner cylinder of the workpiece are discharged through the chip removal channel, thereby preventing the accumulation of waste chips on the positioning surface or cutting area from the source, ensuring the tight fit between the workpiece and the positioning surface and the stable contact between the tool and the workpiece.

[0028] To further optimize the technical solution, the linear motion component includes:

[0029] A linear guide rail, the extension of which passes through the workpiece positioning center;

[0030] A slide table, which is slidably mounted on a linear guide rail, and a chuck is mounted on the slide table.

[0031] To further optimize the technical solution, the base structure is also provided with multiple limiting plates, each of which is respectively set on the moving path of the linear moving component to limit the moving position of the linear moving component.

[0032] Secondly, this utility model provides a processing system, including:

[0033] Positioning fixtures;

[0034] A turntable, wherein the positioning fixture is positioned on the turntable and rotates under the drive of the turntable, so as to process the workpiece by means of a cutting tool.

[0035] The aforementioned positioning fixture has the same beneficial effects as the positioning fixture of the first aspect of this utility model, and will not be described in detail here. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 A schematic diagram of the structure of a positioning tool provided by this utility model;

[0038] Figure 2 A top view of a positioning fixture provided by this utility model;

[0039] Figure 3 A bottom view of a positioning fixture provided by this utility model;

[0040] Figure 4 A side view of a positioning fixture provided by this utility model;

[0041] Figure 5 A front view of the base of a positioning fixture provided by this utility model;

[0042] Figure 6 A rear view of the base of a positioning fixture provided by this utility model;

[0043] Figure 7 A first-view structural schematic diagram of the mandrel of a positioning tool provided by this utility model;

[0044] Figure 8 A second-view structural schematic diagram of the mandrel of a positioning tool provided by this utility model;

[0045] Figure 9 A schematic diagram of the structure of a locking disc for a positioning tool provided by this utility model;

[0046] Figure 10 A top view of a positioning fixture provided by this utility model;

[0047] Figure 11 This utility model Figure 10 Sectional view along line A-A;

[0048] Figure 12 This is a schematic diagram of a processing system provided by the present invention.

[0049] Figure label:

[0050] 1. Base; 11. Linear guide rail limiting groove; 12. Spindle limiting hole; 13. First countersunk hole; 14. High-strength screw; 15. Second countersunk hole.

[0051] 2. Mandrel; 21. First column; 22. Second column; 23. Third column; 24. Drain port; 25. External thread; 26. Workpiece positioning surface; 27. Clear hole; 28. Boss surface; 29. ​​Screw hole.

[0052] 3. Clamping structure; 31. Claw; 32. Linear guide rail; 33. Slide table; 34. First dust cover; 35. Turntable; 36. Connecting rod; 37. Pin; 38. First swing arm.

[0053] 4. Locking structure; 41. Locking disc; 411. Internal thread; 412. Locking hole; 42. Second rocker arm; 43. Second dust cover; 44. Limiting plate.

[0054] 5. Turntable;

[0055] 6. Workpiece. Detailed Implementation

[0056] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0057] The following is combined Figures 1 to 12 As shown, the positioning tooling of the first aspect of the present invention and the processing system of the second aspect of the present invention are described in detail.

[0058] According to an embodiment of the present invention, in a first aspect, a positioning fixture is provided, combined with... Figures 1 to 11 As shown, the device includes a base structure and a clamping structure 3. The base structure has a workpiece positioning surface 26 with a workpiece positioning center. The clamping structure 3 includes a drive assembly, multiple jaws 31, and multiple linear movement assemblies. The linear movement assemblies are connected to the jaws 31, and are evenly spaced circumferentially on the base structure. The drive assembly is adapted to drive each linear movement assembly and jaws 31 to move synchronously in a direction pointing towards or away from the workpiece positioning center.

[0059] The aforementioned positioning fixture, combined with a gear-shaping power head, enables mass production of internal splines in ceramic threaded components. By setting multiple linear moving components and jaws evenly spaced circumferentially, and cooperating with the drive component to achieve synchronous movement, it can provide uniform and symmetrical clamping force for the irregular structure of ceramic threaded components, avoiding the cumbersome adjustment steps caused by structural irregularities in traditional clamping methods. This embodiment solves the problems of difficult machining of internal splines in ceramic threaded components and the cumbersome and complex clamping of internal spline machining in ceramic threaded components, improving clamping efficiency by more than 5 times.

[0060] Each linear moving component is evenly distributed circumferentially and moves synchronously toward or away from the workpiece positioning center, ensuring that the clamping center of the chuck for the ceramic threaded element is consistent with the positioning center of the workpiece positioning surface, effectively solving the problem of inaccurate repetitive positioning in traditional methods. Because the synchronously moving chuck can precisely align with the positioning center, the time required for repeated calibration using a dial indicator after clamping is significantly reduced, increasing work efficiency by more than 5 times.

[0061] In some embodiments, the base structure includes a base 1 and a mandrel 2. A mandrel limiting hole 12 is provided on the base 1. The mandrel 2 is positioned within the mandrel limiting hole 12 and extends upward from the base 1, with its top surface serving as a workpiece positioning surface 26. The mandrel 2 is detachably mounted to the base 1 through the mandrel limiting hole 12. The chuck 31 moves horizontally, and the workpiece is vertically positioned on the mandrel 2. When connecting the mandrel 2 to the base 1, a high-strength screw 14 is used to pass through the first countersunk hole 13 on the reverse side of the base and the screw hole 29 on the mandrel 2, thereby locking the base 1 and the mandrel 2 together. The front side of the base 1 is in contact with the boss surface 28 of the mandrel 2, ensuring the firmness and verticality accuracy of the mandrel 2 and the steel base.

[0062] When the workpiece positioning surface 26 is worn or the processing requirements change, only the mandrel 2 needs to be replaced, without replacing the entire base 1, which reduces maintenance costs and downtime. The top surface of the mandrel 2 serves as the positioning surface, providing point / surface contact support for structures such as the inner hole of ceramic threaded components. This, together with the clamping force of the circumferential jaws, forms a synergistic effect of center positioning and peripheral clamping, better meeting the clamping requirements of irregular workpieces.

[0063] In some embodiments, the drive assembly includes a turntable 35, connecting rods 36, and a first rocker arm 38. The turntable is rotatably mounted on a spindle 2 extending upward from the base 1. Multiple connecting rods 36 are provided, one end of each connecting rod 36 being hinged to the turntable 35 via a first hinge seat, and the other end of each connecting rod 36 being hinged to a linear motion assembly via a second hinge seat. The first rocker arm 38 is connected to the side wall of the turntable 35, and when an external force is applied to the first rocker arm 38, the first rocker arm 38 drives the turntable 35 to rotate.

[0064] The turntable 35 is directly mounted on the spindle 2 and rotates. The connecting rod 36 connects the turntable 35 and the linear motion component, making full use of the vertical space above the base. As a rigid transmission component, the connecting rod 36 converts the rotational motion of the turntable 35 into the linear motion of the linear motion component.

[0065] The turntable 35 is hinged to each linear moving component via multiple connecting rods 36. When the turntable 35 rotates around the spindle 2, each connecting rod 36 synchronously pushes or pulls the corresponding linear moving component, enabling multiple jaws to move synchronously towards or away from the workpiece positioning center along the circumference. This turntable-connecting rod linkage design ensures a high degree of consistency in jaw movements from a mechanical structure perspective, avoiding clamping deviations caused by asynchronous movements when multiple jaws are driven independently in traditional methods, and significantly improving the repeatability of ceramic threaded components.

[0066] By using the design of the first lever 38 to drive the turntable, the rotational driving force is concentrated on a single lever. The operator only needs to apply a small external force to the first lever 38, such as by manually turning it or using a simple tool, to complete the synchronous opening and closing of the multiple jaws. Compared with the cumbersome operation of adjusting multiple jaws separately in traditional methods, this significantly reduces the difficulty of clamping and shortens the clamping time.

[0067] In some embodiments, the drive component is located below the jaw 31, and there is an accommodating space between the drive component and the jaw 31. More specifically, there is an accommodating space between the turntable 35 and the jaw 31, and a locking structure 4 suitable for locking and positioning the drive component is provided within the accommodating space. The locking structure can rigidly lock the position of the drive component after the jaw moves to the target position by the drive component, thereby locking the jaw and preventing the jaw from accidentally sliding or shifting due to external interference such as equipment vibration and cutting force impact during the processing. This effectively solves the problem of decreased positioning accuracy caused by loose clamping during the processing of ceramic threaded components.

[0068] More specifically, the mandrel 2 has an external thread 25 on its outer wall extending upward from the base 1. The locking structure 4 includes a locking disc 41 and a second rocker arm 42. The locking disc 41 is annular, and its inner ring wall has an internal thread 411. The locking disc 41 is threaded onto the mandrel 2. The second rocker arm 42 is connected to the locking disc 41. When an external force is applied to the second rocker arm 42, the second rocker arm 42 drives the locking disc 41 to rotate and rise along the mandrel 2. When the locking disc 41 contacts the top wall of the turntable 35 in the drive assembly, the locking disc 41 locks the turntable 35, thereby locking each of the pawls 31. Figure 9 As shown, multiple locking holes 412 are provided on the outer wall of the locking disc 41, and the second rocker arm 42 can be connected to one of the locking holes 412.

[0069] When the operator drives the locking disc to rotate via the second rocker arm 42, the rising height of the locking disc can be precisely adjusted by controlling the number of rotations, thereby accurately controlling the clamping force on the bottom wall of the chuck. At the same time, the self-locking property of the threaded pair ensures that the locking disc automatically maintains its current position after operation stops, preventing the locking disc 41 from loosening due to machining vibration, and providing a continuous and stable locking force for the chuck 31.

[0070] Combination Figure 7 and Figure 8 As shown, the mandrel 2 is divided into a first column 21, a second column 22, and a third column 23, which are coaxially connected. The first column 21 is located inside the mandrel limiting hole 12. The diameter of the second column 22 is larger than that of the first column 21 and the third column 23, respectively. The second column 22 is connected to the base 1 by fasteners. The external thread 25 is provided on the outer wall surface of the third column 23, and the fastener is a bolt. The bottom end face of the second column 22 is a boss surface 28.

[0071] If the waste chips generated during the machining of the inner cylinder of ceramic threaded components remain between the workpiece and the positioning surface, it will cause poor contact between the workpiece and the positioning surface, leading to clamping misalignment or machining datum deviation. To solve this problem, a chip removal channel is provided through the mandrel 2. After the workpiece is positioned by the clamping structure 3, the inner cylinder of the workpiece corresponds to the chip removal channel, so that the waste chips generated after machining the inner cylinder of the workpiece can be discharged through the chip removal channel, preventing the accumulation of waste chips on the positioning surface or cutting area from the source, ensuring a tight fit between the workpiece and the positioning surface and stable contact between the tool and the workpiece.

[0072] More specifically, the chip removal channel includes a drain port 24 and a vent hole 27 connected between them. The drain port 24 is located on the first column 21, and the vent hole 27 is located on the second column 22 and the third column 23. Both the drain port 24 and the vent hole 27 are circular holes.

[0073] In some embodiments, the base 1 has multiple linear guide rail limiting grooves 11. The linear movement assembly includes a linear guide rail 32 and a slide table 33. The linear guide rail 32 is disposed within the linear guide rail limiting groove 11, and the extension line of the linear guide rail 32 passes through the workpiece positioning center. The slide table 33 is slidably mounted on the linear guide rail 32, and a chuck 31 is disposed on the slide table 33.

[0074] When connecting the base 1 and the chuck 31, first install the linear guide rail 32 in the linear guide rail limiting groove 11 on the front of the base and fix it with screws; then install the slide table 33 on the linear guide rail 32 and fix it with screws; finally, install the chuck 31 on the slide table 33 and fix it with screws, and put the first dust cover 34 on the chuck 31 to prevent dust from entering. The movement of the linear guide rail 32 can drive the chuck 31 to clamp the workpiece 6.

[0075] In some embodiments, the base structure is further provided with a plurality of limiting plates 44, each of which is respectively disposed on the moving path of the linear moving component to limit the moving position of the linear moving component, limit the opening and closing degree of the claws, and prevent the claws from opening and closing excessively.

[0076] In the aforementioned positioning fixture, when connecting the mandrel 2 and the chuck 31, the turntable 35 and the locking plate 41 are first fixed to the mandrel 2. The internal thread 411 of the locking plate 41 engages with the external thread of the mandrel 2, thus locking and securing it. Then, the turntable 35 is connected to the slide table 33 via the connecting rod 36 and the pin 37. The first rocker arm 38 is tightened onto the turntable 35, and the second rocker arm 42 is tightened onto the locking plate 41, facilitating the rotation of the turntable 35 and the locking plate 41 to clamp and lock the workpiece 6. Finally, the second dust cover 43 is installed on the locking plate 41 to prevent dust from entering the mandrel 2, the locking plate 41, and the turntable 35.

[0077] Place the ceramic workpiece at the center of the three jaws, with the bottom of the ceramic workpiece in contact with the positioning surface of the mandrel workpiece. First, move the first rocker arm 38 on the turntable 35 to move the jaw 31 and clamp the ceramic workpiece. Then, move the second rocker arm 42 on the locking plate 41 to lock the ceramic workpiece. At this point, the ceramic workpiece will be fixed in the exact center of the three jaws. The jaws are perpendicular to the base and the mandrel, and the ceramic workpiece is also in a vertical position. After simple centering with a dial indicator, internal spline machining can be performed.

[0078] According to an embodiment of the present invention, in a second aspect, a processing system is provided, combined with... Figure 12 As shown, it includes a positioning fixture and a rotary table 5. The positioning fixture is positioned on the rotary table 5 and rotates under the drive of the rotary table 5 to process the workpiece 6 by means of a cutting tool. The rotary table 5 can be a four-axis rotary table.

[0079] When connecting the positioning fixture to the four-axis rotary table, the installed positioning fixture is assembled onto the four-axis rotary table. Countersunk screws are passed through the four second countersunk holes 15 in the base to lock the positioning fixture onto the four-axis rotary table. During operation, the four-axis rotary table rotates under program control, causing the positioning fixture to rotate. The cutting fluid is sprayed onto the ceramic workpiece and tool, flowing from the mandrel drain port to the four-axis rotary table drain port, and then back to the machine tool's circulating water tank. Its function is to cool the workpiece and tool while carrying away grinding powder, thereby achieving the internal spline machining of ceramic threaded components.

[0080] The specific method for machining the internal spline teeth of ceramic threaded components using the above-mentioned machining system is as follows:

[0081] Step 1: Assemble the installed positioning fixture onto the four-axis rotary table and tighten it using the four countersunk screws on the base.

[0082] Step 2: Place the ceramic workpiece in the center of the three jaws, with the bottom of the ceramic workpiece aligned with the workpiece positioning surface of the mandrel. First, turn the first rocker arm 38 on the turntable 35. The connecting rod 36, connected to the turntable 35, moves the slide 33 and jaws 31 toward the ceramic workpiece until the workpiece is clamped. Then, turn the second rocker arm 42 on the locking disc 41. The locking disc 41 is threadedly connected to the mandrel 2, pressing the turntable 35 to prevent it from moving. At the same time, the jaws 31 lock the ceramic workpiece. At this point, the ceramic workpiece is fixed in the exact center of the three jaws. The jaws 31 are perpendicular to the base 1 and the mandrel 2, and the ceramic workpiece is also in a vertical position.

[0083] Step 3: Input the machining program and use a mechanical gauge to determine the inner and outer circle centers of the ceramic workpiece. Once confirmed to be correct, you can start machining the internal spline.

[0084] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A positioning fixture, characterized in that, include: A base structure, wherein a workpiece positioning surface (26) is provided on the base structure, and the workpiece positioning surface (26) has a workpiece positioning center; The clamping structure (3) includes a drive component, multiple jaws (31) and multiple linear moving components. The linear moving components are connected to the jaws (31). Each of the linear moving components is evenly spaced on the base structure in the circumferential direction. The drive component is adapted to drive each linear moving component and the jaws (31) to move synchronously in a direction pointing towards or away from the workpiece positioning center.

2. The positioning fixture according to claim 1, characterized in that, The base structure includes: A base (1) is provided with a spindle limiting hole (12); The mandrel (2) is positioned in the mandrel limiting hole (12) and extends upward from the base (1). The top surface of the mandrel (2) is the workpiece positioning surface (26).

3. The positioning fixture according to claim 2, characterized in that, The driving component includes: A turntable (35) is rotatably mounted on a spindle (2) extending upward from the base (1); Multiple links (36), one end of each link (36) is hinged to a turntable (35), and the other end of each link (36) is hinged to a linear motion component; The first pendulum (38) is connected to the side wall of the turntable (35). When an external force is applied to the first pendulum (38), the first pendulum (38) drives the turntable (35) to rotate.

4. The positioning fixture according to claim 2, characterized in that, The drive component is located below the claw (31), and there is an accommodating space between the drive component and the claw (31). A locking structure (4) suitable for locking and positioning the drive component is provided in the accommodating space.

5. The positioning fixture according to claim 4, characterized in that, The mandrel (2) has an external thread (25) on its outer wall surface extending upward from the base (1); The locking structure (4) includes a locking disc (41) and a second rocker arm (42); the locking disc (41) is annular, and an internal thread (411) is provided on the inner ring wall of the locking disc (41). The locking disc (41) is threaded onto the spindle (2); the second rocker arm (42) is connected to the locking disc (41). When an external force is applied to the second rocker arm (42), the second rocker arm (42) drives the locking disc (41) to rotate and rise along the spindle (2). When the locking disc (41) contacts the top wall of the drive assembly, the locking disc (41) locks the drive assembly.

6. The positioning fixture according to claim 5, characterized in that, The mandrel (2) is divided into a first column (21), a second column (22) and a third column (23) connected coaxially. The first column (21) is located in the mandrel limiting hole (12). The diameter of the second column (22) is larger than that of the first column (21) and the third column (23) respectively. The second column (22) is connected to the base (1) by fasteners. The external thread (25) is located on the outer wall surface of the third column (23).

7. The positioning fixture according to claim 2, characterized in that, A chip removal channel is provided through the mandrel (2); after the workpiece is positioned by the clamping structure (3), the inner cylinder of the workpiece corresponds to the chip removal channel so that the waste chips after processing the inner cylinder of the workpiece are discharged through the chip removal channel.

8. The positioning fixture according to any one of claims 1-7, characterized in that, The linear motion component includes: Linear guide (32), the extension line of which passes through the workpiece positioning center; The slide (33) is slidably mounted on the linear guide rail (32), and the claw (31) is disposed on the slide (33).

9. The positioning fixture according to any one of claims 1-7, characterized in that, The base structure is also provided with a plurality of limiting plates (44), each of which is respectively set on the moving path of the linear moving component to limit the moving position of the linear moving component.

10. A processing system, characterized in that, include: The positioning fixture according to any one of claims 1-9; Turntable (5), the positioning fixture is positioned on the turntable (5) and rotates under the drive of the turntable (5) to process the workpiece by means of a cutting tool.

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