18-piece inner expansion lathe tooling

Abstract

This application relates to an 18-lobed internal expansion lathe fixture, belonging to the technical field of precision machining. It includes a clamping outer sleeve, an expansion inner sleeve, a drive assembly, and a detection assembly. The clamping outer sleeve is mounted on a lathe. A tapered pull-in shaft is fixedly disposed on the side of the clamping outer sleeve away from the lathe. A bearing shell is fixedly disposed on the clamping outer sleeve for supporting the workpiece. The expansion inner sleeve is sleeved on the tapered pull-in shaft and located between the tapered pull-in shaft and the bearing shell. Multiple independent lobes are fixedly disposed circumferentially on the expansion inner sleeve. The drive assembly is located on the clamping outer sleeve and is used to drive the expansion inner sleeve to slide axially, causing the independent lobes to expand and contract radially via the conical surface of the tapered pull-in shaft. The detection assembly is located on the independent lobes and is used to detect the elastic properties of the independent lobes. This application effectively solves the problem of workpiece deformation easily caused by existing clamping methods for thin-walled annular parts.

Description

Technical Field

[0001] This application relates to the technical field of precision machining, and in particular to an 18-lobed internal expansion lathe tooling. Background Technology

[0002] Internal expansion lathe fixtures are specialized jigs used in precision machining for high-precision turning of thin-walled ring parts. By converting axial tension into uniform radial expansion force, they achieve deformation-free clamping of thin-walled ring parts, ensuring the dimensional accuracy, roundness, coaxiality, and other key geometric tolerances of the workpiece's inner and outer circles. They are widely used in the batch processing of high-precision thin-walled ring parts such as bearing rings, precision sealing rings, and hydraulic valve sleeves in industries such as bearing manufacturing, precision machinery, aerospace, and automotive parts.

[0003] Currently, lathe machining of thin-walled ring-shaped parts mainly employs two clamping methods: external clamping with a three-jaw chuck or internal clamping with an integral internal expansion mandrel. The three-jaw chuck clamping method uses the point contact of three jaws to clamp the outer diameter of the workpiece, achieving positioning and fixation. The integral internal expansion mandrel clamping method involves mounting the workpiece on an integral tapered mandrel, and using axial pushing or pulling of the mandrel to cause radial expansion, thus clamping the inner hole of the workpiece. In use, the operator mounts the thin-walled ring-shaped part to be machined on the corresponding fixture, adjusts the clamping force to a suitable range, and starts the lathe for turning. After machining, the fixture is released, and the machined workpiece is removed.

[0004] Existing clamping methods for thin-walled ring parts have several shortcomings in actual machining: Three-jaw chucks use point-contact clamping, and the concentrated clamping force can easily cause local plastic deformation of thin-walled, low-rigidity ring parts, resulting in non-circular contours after machining, which cannot meet the requirements of high-precision geometric tolerances; Although integral internal expansion mandrels achieve internal hole positioning, the mandrel itself inevitably has roundness errors during manufacturing. During expansion, these uneven shape errors are forcibly transmitted to the workpiece, causing the workpiece to deform to adapt to the shape of the mandrel. After machining is completed and the clamp is released, the internal stress of the workpiece is released, resulting in springback deformation, which leads to a significant decrease in the final dimensional, roundness, and coaxiality accuracy, failing to meet the drawing requirements; At the same time, the uneven distribution of the expansion force of integral mandrels can easily cause excessive local stress on the workpiece, resulting in micro-cracks, and the low repeatability accuracy makes it difficult to meet the batch, stable, and high-quality machining requirements of high-precision thin-walled ring parts. Summary of the Invention

[0005] To address the problems of workpiece deformation, low precision, and uneven distribution of clamping force caused by existing thin-walled ring clamping methods, this application provides an 18-lobed internal expansion lathe fixture.

[0006] This application provides an 18-lobed internal expansion lathe fixture, which adopts the following technical solution: An 18-lobed internal expansion lathe fixture includes a clamping outer sleeve, an expansion inner sleeve, a drive assembly, and a detection assembly. The clamping outer sleeve is mounted on a lathe. A tapered pull-in shaft is fixedly disposed on the side of the clamping outer sleeve away from the lathe. A bearing shell is fixedly disposed on the clamping outer sleeve for supporting the workpiece. The expansion inner sleeve is sleeved on the tapered pull-in shaft and located between the tapered pull-in shaft and the bearing shell. Multiple independent lobes are fixedly disposed on the expansion inner sleeve circumferentially. The drive assembly is located on the clamping outer sleeve and is used to drive the expansion inner sleeve to slide axially, thereby causing the independent lobes to expand and contract radially by means of the tapered surface of the tapered pull-in shaft. The detection assembly is located on the independent lobes and is used to detect the elastic properties of the independent lobes.

[0007] By adopting the above technical solution, when it is necessary to clamp a thin-walled annular part, the operator puts the workpiece on the bearing shell, and the driving component drives the expansion inner sleeve to slide axially along the tapered pull-in shaft. With the help of the tapered surface of the tapered pull-in shaft, multiple independent petals expand radially synchronously, uniformly tightening the inner hole of the workpiece to achieve deformation-free clamping. The detection component monitors the elastic reset performance of each independent petal in real time, promptly detects the risk of fatigue failure, and ensures the stability and consistency of batch processing.

[0008] Optionally, an end face protective plate is fixedly provided on the side of the tapered pull-in shaft away from the clamp fixing sleeve.

[0009] By adopting the above technical solution, the end face protection plate can prevent chips and coolant from entering the tooling during the machining process, protect the mating surfaces of the tapered pull-in shaft and the expansion inner sleeve, and extend the service life of the tooling.

[0010] Optionally, the drive assembly includes a drive plate, a sliding sleeve, and a connecting bolt; the drive plate is slidably disposed inside the fixture fixing sleeve, and a hydraulic cylinder is provided on one side, the hydraulic cylinder is mounted on a lathe, and its telescopic end is fixedly connected to the drive plate; the sliding sleeve passes through the fixture fixing sleeve, and its two ends abut against the drive plate and the expansion inner sleeve respectively; the connecting bolt passes through the expansion inner sleeve, the fixture fixing sleeve, and the drive plate in sequence, and is locked with a nut.

[0011] By adopting the above technical solution, during use, the piston rod of the hydraulic cylinder retracts, driving the drive plate to slide smoothly along the axial direction within the cylindrical drive cavity of the clamping sleeve. When the drive plate slides, it pushes multiple sets of circumferentially evenly distributed sliding sleeves to move synchronously. The sliding sleeves evenly transmit the axial force to the entire end face of the expansion inner sleeve, driving the expansion inner sleeve to slide axially along the conical pull-in shaft. With the help of the conical surface, multiple independent petals synchronously expand radially to support and tighten the workpiece. After processing, the piston rod of the hydraulic cylinder extends and resets, and the drive plate pulls the expansion inner sleeve to slide axially in the opposite direction through the sliding sleeve, realizing the radial contraction and reset of the independent petals, thus completing the disassembly of the workpiece.

[0012] Optionally, multiple sets of the sliding sleeve and the connecting bolt are provided at intervals along the circumference of the clamp fixing sleeve.

[0013] By adopting the above technical solution, multiple sets of sliding sleeves and connecting bolts are evenly distributed circumferentially, so that the axial driving force is evenly applied to the entire circumference of the expansion inner sleeve, ensuring that the radial expansion and contraction of multiple independent petals are consistent, and further improving the roundness and coaxiality accuracy of workpiece clamping.

[0014] Optionally, each of the independent petals has a receiving groove and an alignment groove on both sides, with the receiving groove and alignment groove on two adjacent independent petals facing each other; multiple sets of the detection components are provided, each corresponding to one of the multiple independent petals; the detection components include a detection telescopic rod, a mounting plate, an alignment block, a drive telescopic rod, and a connecting pipe; the detection telescopic rod is located in the receiving groove, and its fixed end is fixedly connected to the independent petal; the rod-side cavity of the detection telescopic rod is filled with liquid, and a return spring is provided in the rodless cavity of the detection telescopic rod; the two ends of the return spring are fixedly connected to the movable end and the fixed end of the detection telescopic rod, respectively, and the return spring is in a compressed state; the mounting plate The alignment block is located within the alignment groove; it is slidably disposed within the alignment groove, with one end abutting against the movable end of the detection telescopic rod. A drive spring is provided on one side of the alignment block, and both ends of the drive spring are fixedly connected to the alignment block and the mounting plate, respectively. The drive spring is in a compressed state, and its preset elastic force is greater than the preset elastic force of the reset spring. The drive telescopic rod is located on the side of the independent flap away from the tensioning inner sleeve, and its fixed end is fixedly connected to the independent flap. The rodless cavity of the drive telescopic rod is filled with liquid, and a baffle is fixedly disposed on the movable end of the drive telescopic rod. Both ends of the connecting pipe are connected to the rod cavity of the detection telescopic rod and the rodless cavity of the drive telescopic rod, respectively.

[0015] By adopting the above technical solution, in the initial state, both the reset spring and the drive spring are in a compressed state. Because the drive spring has a greater elastic force, the alignment block always presses against the movable end of the detection telescopic rod, keeping the detection telescopic rod in a compressed state. The movable end of the drive telescopic rod is fully retracted, and the baffle is flush with the outer surface of the independent petals. During use, the independent petals expand radially, increasing the gap between adjacent independent petals. The drive spring extends to reset, pushing the alignment block to slide into the receiving groove of the adjacent independent petals. At this time, because the elastic force of the drive spring is always greater than that of the reset spring, the alignment block continues to press against the movable end of the detection telescopic rod, keeping the detection telescopic rod in a compressed state. The liquid does not flow, and the movable end of the drive telescopic rod remains retracted. After processing, if the independent petals elastically reset normally, all independent petals synchronously retract radially to their initial positions, and adjacent independent petals... The receiving groove of the disc aligns with the alignment groove, and the alignment block resets to its initial state. If an independent disc fails to fully reset due to elastic failure, the receiving groove and alignment groove of the disc and the adjacent disc will be radially misaligned. At this time, the alignment block is blocked by the side wall of the adjacent independent disc (not the side wall of the receiving groove), and the movable end of the detection telescopic rod also disengages from the alignment block and faces the side wall of the adjacent independent disc. After the reset spring loses the clamping force of the alignment block, it resets and extends, pushing the movable end of the detection telescopic rod to extend. The liquid in the rod-side cavity of the detection telescopic rod flows to the rodless cavity of the driving telescopic rod, and the movable end of the driving telescopic rod extends accordingly. The baffle protrudes from the outer circular surface of the independent disc. After the fixture is loosened and reset, the operator can visually identify the failed disc. This structure realizes detection through pure mechanical logic of elastic difference + misalignment trigger, which avoids false triggering during the tightening process from the root.

[0016] Optionally, the detection assembly further includes an adjusting telescopic rod; the mounting plate is slidably connected to the independent flap, and the rod-side cavity of the driving telescopic rod is filled with liquid; the adjusting telescopic rod is embedded in the side wall of the alignment groove, and its movable end is fixedly connected to the mounting plate, the rodless cavity of the adjusting telescopic rod is filled with liquid, and the rodless cavity of the adjusting telescopic rod is connected to the rod-side cavity of the driving telescopic rod through a pipe.

[0017] By adopting the above technical solution, when the failure of an independent petal causes the detection telescopic rod to extend and the movable end of the driving telescopic rod to extend, the liquid in the rod-side chamber of the driving telescopic rod flows to the rodless chamber of the adjusting telescopic rod; the movable end of the adjusting telescopic rod extends accordingly, pushing the mounting plate to move the alignment block, automatically compensating for the positional deviation caused by the petal misalignment; thus ensuring that the alignment block of the failed independent petal is always aligned with the detection telescopic rod of the adjacent normal independent petal, thereby preventing normal petals from being mistakenly judged as failed.

[0018] Optionally, the end face protective plate is provided with an adjustment component, which is used to prevent the baffle from being accidentally extended due to slight deformation.

[0019] By adopting the above technical solution, the adjustment component can adjust the trigger threshold of the detection system, filter out the trace elastic deformation signal when the independent petals are working normally, prevent the baffle from being accidentally triggered to extend, and improve the reliability and anti-interference capability of the detection system.

[0020] Optionally, the adjustment assembly includes a transfer box, a partition, an adjusting screw, and a connecting branch pipe; an overflow valve is installed on the connecting pipe; the transfer box is fixedly mounted on the end face protective plate; the partition is slidably disposed inside the transfer box and divides the transfer box into a liquid accumulation chamber and an adjustment chamber; the adjusting screw is threaded into the transfer box, and one end abuts against the partition; both ends of the connecting branch pipe are respectively connected to multiple connecting pipes and the liquid accumulation chamber of the transfer box, and the connection point between the connecting branch pipe and the connecting pipe is located between the overflow valve and the detection telescopic rod.

[0021] By adopting the above technical solution, the operator rotates the adjusting screw to move the baffle, changing the volume of the liquid accumulation chamber, thereby adjusting the liquid pressure threshold in the connecting pipe. When the independent flap undergoes slight deformation, a small amount of liquid discharged by the detection telescopic rod flows into the liquid accumulation chamber of the transfer box through the connecting branch pipe, without triggering the overflow valve to open, and the baffle remains in the retracted state. When the independent flap fails to reset and causes significant deformation, the amount of liquid discharged by the detection telescopic rod exceeds the capacity of the liquid accumulation chamber, the pressure in the connecting pipe increases, triggering the overflow valve to open, and the liquid flows in to drive the telescopic rod's rod chamber to push the baffle out, thus achieving precise adjustment of the detection threshold.

[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. By adopting a shrinking inner sleeve structure with multiple independent petals, uniform clamping of the inner hole of the thin-walled annular part is achieved, avoiding workpiece deformation caused by concentrated clamping force; 2. By setting up detection components, the elastic performance of individual flaps can be easily tested; 3. By setting adjustment components, the trigger threshold of the detection components can be easily adjusted. Attached Figure Description

[0023] Figure 1 This is a structural schematic diagram of an embodiment of this application; Figure 2 This is a cross-sectional view of an embodiment of this application; Figure 3 This is a partial cross-sectional view of an embodiment of the present application for displaying the detection telescopic rod; Figure 4 This is a cross-sectional view of the partition in an embodiment of this application.

[0024] Explanation of reference numerals in the attached drawings: 1. Fixture fixing sleeve; 11. Tapered pull-in shaft; 111. End face protective plate; 12. Bearing outer shell; 13. Locking plate; 131. Locking bolt; 2. Expansion inner sleeve; 21. Independent flap; 211. Receiving groove; 212. Alignment groove; 3. Drive assembly; 31. Drive plate; 311. Hydraulic cylinder; 32. Sliding sleeve; 33. Connecting bolt; 4. Detection assembly; 41. Detection telescopic rod; 411. Return spring; 42. Mounting plate; 43. Alignment block; 431. Drive spring; 44. Drive telescopic rod; 441. Baffle; 45. Connecting pipe; 451. Overflow valve; 46. Adjusting telescopic rod; 5. Adjusting assembly; 51. Transfer box; 52. Partition; 53. Adjusting screw; 54. Connecting branch pipe. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0026] This application discloses an 18-lobed internal expansion lathe fixture. (Refer to...) Figure 1 and Figure 2 An 18-lobed internal expansion lathe fixture includes a clamping outer sleeve 1, an expansion inner sleeve 2, a drive assembly 3, a detection assembly 4, and an adjustment assembly 5. The clamping outer sleeve 1 is mounted on the lathe. A tapered pull-in shaft 11 is fixedly mounted on the side of the clamping outer sleeve 1 away from the lathe, and the outer tapered surface of the tapered pull-in shaft 11 gradually narrows towards the direction away from the clamping outer sleeve 1. A bearing housing 12 is coaxially fixed on the clamping outer sleeve 1, and the bearing housing 12 is used to support the thin-walled annular workpiece to be processed. The expansion inner sleeve 2 is coaxially sleeved on the tapered pull-in shaft 11 and located between the tapered pull-in shaft 11 and the bearing housing 12. The expansion inner sleeve 2 has 18 independent lobes 21 evenly divided circumferentially, and each independent lobe 21 can expand and contract independently radially. The drive assembly 3 is located inside the clamp fixing sleeve 1 and is used to drive the expansion inner sleeve 2 to slide axially along the tapered pull-in shaft 11. The tapered surface of the pull-in shaft 11 causes all individual flaps 21 to synchronously generate radial expansion and contraction movements. The detection assembly 4 is disposed on each individual flap 21 and is used to detect the elastic reset performance of the individual flaps 21 in real time, promptly identifying flaps that have failed due to fatigue. The adjustment assembly 5 is located on one side of the clamp fixing sleeve 1 and is used to adjust the trigger threshold of the detection assembly 4.

[0027] Reference Figure 1 and Figure 2 A tapered pull-in shaft 11 is coaxially fixed with an end face guard plate 111 on the side away from the fixture fixing sleeve 1. The end face guard plate 111 is circular. A locking plate 13 is provided on one side of the fixture fixing sleeve 1. The locking plate 13 is fixedly connected to the lathe. A locking bolt 131 is provided on the locking plate 13. The locking bolt 131 passes through the locking plate 13 and locks the fixture fixing sleeve 1 onto the locking plate 13.

[0028] Reference Figure 2 and Figure 3 The inner sleeve 2 is cylindrical in shape and is made of spring steel. After being machined as a whole, it is evenly divided into 18 independent segments 21 along the circumference by wire cutting. The inner surface of each independent segment 21 is machined with an inner conical surface that mates with the outer conical surface of the tapered pull-in shaft 11. Each independent segment 21 has a receiving groove 211 and an alignment groove 212 on its two sides, and the receiving groove 211 and the alignment groove 212 on two adjacent independent segments 21 are aligned directly opposite each other.

[0029] Reference Figure 2 The drive assembly 3 includes a drive plate 31, a sliding sleeve 32, and connecting bolts 33. The drive plate 31 is slidably disposed within a cylindrical drive cavity inside the fixture fixing sleeve 1 and can slide freely along the axial direction. A hydraulic cylinder 311 is disposed on the side of the drive plate 31 away from the expansion inner sleeve 2. The cylinder body of the hydraulic cylinder 311 is fixedly mounted on a lathe, and its telescopic end is fixedly connected to the center of the drive plate 31. The sliding sleeve 32 is cylindrical and passes through guide holes evenly spaced circumferentially on the end face of the fixture fixing sleeve 1. The two ends of the sliding sleeve 32 abut against the end faces of the drive plate 31 and the expansion inner sleeve 2, respectively. The connecting bolts 33 pass sequentially through the expansion inner sleeve 2, the fixture fixing sleeve 1, and the drive plate 31, and are locked with nuts to connect the expansion inner sleeve 2 and the drive plate 31 into a whole. Three sets of sliding sleeves 32 and connecting bolts 33 are spaced apart circumferentially along the fixture fixing sleeve 1 to ensure uniform transmission of axial driving force.

[0030] Reference Figure 2 , Figure 3 and Figure 4 The detection assembly 4 has 18 sets, each corresponding to one of the 18 independent petals 21. The detection assembly 4 includes a detection telescopic rod 41, a mounting plate 42, an alignment block 43, a drive telescopic rod 44, a connecting pipe 45, and an adjusting telescopic rod 46. The detection telescopic rod 41 is horizontally positioned within the receiving groove 211, with its fixed end fixedly connected to the independent petals 21. The rod-side cavity of the detection telescopic rod 41 is filled with liquid, and a return spring 411 is installed in the rodless cavity of the detection telescopic rod 41. The two ends of the return spring 411 are fixedly connected to the movable end and the fixed end of the detection telescopic rod 41, respectively, and the return spring 411 is always in a compressed state.

[0031] Mounting plate 42 is slidably disposed within alignment groove 212. Alignment block 43 is slidably disposed within alignment groove 212, with one end abutting against the movable end face of detection telescopic rod 41. The end of alignment block 43 near detection telescopic rod 41 is hemispherical, and a drive spring 431 is provided at one end of alignment block 43. The two ends of drive spring 431 are fixedly connected to mounting plate 42 and alignment block 43 respectively. Drive spring 431 is always in a compressed state, and its preset elastic force is greater than the preset elastic force of reset spring 411.

[0032] The drive telescopic rod 44 is located on the side of the independent flap 21 away from the expansion inner sleeve 2, and its fixed end is fixedly connected to the independent flap 21. Both the rodless cavity and the rod cavity of the drive telescopic rod 44 are filled with liquid. A baffle 441 is fixedly installed on the movable end of the drive telescopic rod 44, and the outer surface of the baffle 441 is flush with the outer circular surface of the independent flap 21. The two ends of the connecting pipe 45 are respectively connected to the rod cavity of the detection telescopic rod 41 and the rodless cavity of the drive telescopic rod 44, and an overflow valve 451 is installed on the connecting pipe 45. The adjusting telescopic rod 46 is embedded in the side wall of the alignment groove 212, and its movable end is fixedly connected to the mounting plate 42. The rodless cavity of the adjusting telescopic rod 46 is filled with liquid, and the rodless cavity of the adjusting telescopic rod 46 is connected to the rod cavity of the drive telescopic rod 44 through a thin pipe.

[0033] Reference Figure 1 and Figure 4 The regulating assembly 5 includes a transfer box 51, a partition 52, an adjusting screw 53, and a connecting branch pipe 54. The transfer box 51 is rectangular and fixedly positioned at the center of the end face protection plate 111. The partition 52 is slidably disposed inside the transfer box 51, dividing the internal space of the transfer box 51 into a liquid accumulation chamber and a regulating chamber. The adjusting screw 53 is threaded onto the end cap of the transfer box 51, with one end extending into the regulating chamber and abutting against the end face of the partition 52. Rotating the adjusting screw 53 pushes the partition 52 to slide horizontally, thereby changing the volume of the liquid accumulation chamber. One end of the connecting branch pipe 54 is connected to the liquid accumulation chamber of the transfer box 51, and the other end is connected to multiple connecting pipes 45 through multiple branch pipes. The connection point between the connecting branch pipe 54 and the connecting pipes 45 is located between the overflow valve 451 and the detection telescopic rod 41.

[0034] The implementation principle of an 18-lobed internal expansion lathe fixture in this application embodiment is as follows: In the initial state, the piston rod of the hydraulic cylinder 311 is in an extended state, the inner sleeve 2 is located at the small diameter end of the tapered pull-in shaft 11, all independent petals 21 are in a radially contracted state, and the gap between adjacent independent petals 21 is minimal. At this time, both the return spring 411 and the drive spring 431 are in a compressed state. Since the preset elastic force of the drive spring 431 is greater than that of the return spring 411, the alignment block 43 always presses the movable end of the detection telescopic rod 41, keeping the detection telescopic rod 41 in a maximum compressed state. The movable end of the drive telescopic rod 44 is fully retracted, and the baffle 441 is flush with the outer circular surface of the independent petals 21.

[0035] When clamping a thin-walled annular workpiece, the operator places the workpiece onto the outer circumferential surface of the supporting housing 12, ensuring the end face of the workpiece aligns with the end face of the clamping outer sleeve 1. Then, the hydraulic cylinder 311 is activated, causing the piston rod to retract and drive the drive plate 31 to slide smoothly axially within the cylindrical drive cavity. As the drive plate 31 slides, it pushes the sliding sleeve 32 to move synchronously, which in turn drives the expansion inner sleeve 2 to move synchronously, sliding towards the large-diameter end of the tapered pull-in shaft 11. Utilizing the tapered surface of the tapered pull-in shaft 11, the 18 independent lobes 21 synchronously expand radially, uniformly tightening the inner hole of the workpiece and achieving clamping.

[0036] During the radial expansion of the independent flaps 21, the gap between adjacent independent flaps 21 gradually increases. The drive spring 431 returns to its original position and extends, pushing the alignment block 43 to slide into the receiving groove 211 of the adjacent independent flaps 21. Since the elastic force of the drive spring 431 is always greater than that of the return spring 411, the alignment block 43 continues to press against the movable end of the detection telescopic rod 41. The detection telescopic rod 41 remains compressed, the liquid does not flow, the movable end of the drive telescopic rod 44 remains retracted, and the baffle 441 does not extend.

[0037] After the workpiece is clamped, the lathe is started for turning. During the machining process, the end face protective plate 111 prevents chips and coolant from entering the tooling, protecting the mating surfaces of the tapered pull-in shaft 11 and the expansion inner sleeve 2, and extending the tooling's service life.

[0038] After processing, the operator drives the piston rod of the hydraulic cylinder 311 to extend and reset, and the independent petals 21 synchronously retract radially and reset under their own elasticity. If the elastic reset performance of all independent petals 21 is normal, all independent petals 21 retract to their initial position, the receiving grooves 211 and the alignment grooves 212 of adjacent independent petals 21 are always aligned, the alignment block 43 resets to its initial state under the combined action of the reset spring 411 and the drive spring 431, and the baffle 441 remains flush with the outer surface of the independent petals 21.

[0039] If an individual lobe 21 fails due to elastic fatigue after long-term use and cannot fully retract and return to its original position, radial misalignment will occur between this lobe and its adjacent lobe, and the receiving groove 211 and the alignment groove 212 will no longer be aligned. At this time, the alignment block 43 is blocked by the side wall of the adjacent individual lobe 21 and cannot return to its initial position. At the same time, the movable end of the detection telescopic rod 41 also disengages from the alignment block 43 and faces the side wall of the adjacent individual lobe 21. After the return spring 411 loses the clamping force of the alignment block 43, it returns to its original position and extends, pushing the movable end of the detection telescopic rod 41 out. The liquid in the rod-side cavity of the detection telescopic rod 41 is squeezed out and flows through the connecting pipe 45 to the rodless cavity of the driving telescopic rod 44.

[0040] When the failure deformation of the independent flap 21 is small, the small amount of liquid discharged by the detection telescopic rod 41 flows into the liquid accumulation chamber of the transfer box 51 through the connecting branch pipe 54, which will not trigger the opening of the overflow valve 451. The movable end of the drive telescopic rod 44 will not extend, and the baffle 441 remains in the retracted state, avoiding false triggering. When the failure deformation of the independent flap 21 exceeds the set threshold, the amount of liquid discharged by the detection telescopic rod 41 exceeds the capacity of the liquid accumulation chamber. The pressure in the connecting pipe 45 increases, triggering the opening of the overflow valve 451. Liquid flows into the rodless chamber of the drive telescopic rod 44, pushing the movable end of the drive telescopic rod 44 to extend, and the baffle 441 protrudes from the outer surface of the independent flap 21. After the tooling is loosened and reset, the operator can visually identify the failed flap and replace it in time to avoid defective products in batch processing.

[0041] As the movable end of the drive telescopic rod 44 extends, the liquid in the rod chamber of the drive telescopic rod 44 is squeezed out and flows into the rodless chamber of the regulating telescopic rod 46 through the pipe, pushing the movable end of the regulating telescopic rod 46 to extend. The regulating telescopic rod 46 pushes the mounting plate 42 to move the alignment block 43 away from the failed petal, automatically compensating for the positional deviation caused by the misalignment of the petal, so that the alignment block 43 of the failed independent petal 21 is always aligned with the detection telescopic rod 41 of the adjacent normal independent petal 21, preventing normal petals from being mistakenly judged as failed.

[0042] When the trigger threshold of the detection component 4 needs to be adjusted, the operator rotates the adjusting screw 53 to move the partition 52, changing the volume of the liquid accumulation chamber inside the transfer box 51. Increasing the volume of the liquid accumulation chamber allows it to hold more liquid generated by minute deformations, thus raising the trigger threshold; decreasing the volume of the liquid accumulation chamber lowers the trigger threshold. By adjusting the trigger threshold, the system can adapt to the needs of different workpiece specifications and different processing conditions, improving the reliability and adaptability of the detection system.

[0043] The above are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made to the structure, shape, and principle of this application should be covered within the scope of protection of this application.

Claims

1. A lathe fixture with 18 internal expansion lobes, characterized in that: The assembly includes a clamping outer sleeve (1), a tightening inner sleeve (2), a drive assembly (3), and a detection assembly (4); the clamping outer sleeve (1) is mounted on a lathe; a tapered pull-in shaft (11) is fixedly disposed on the side of the clamping outer sleeve (1) away from the lathe, and a bearing shell (12) is fixedly disposed on the clamping outer sleeve (1), the bearing shell (12) being used to support the workpiece; the tightening inner sleeve (2) is sleeved on the tapered pull-in shaft (11) and located on the tapered pull-in shaft. Between (11) and the bearing shell (12), a plurality of independent petals (21) are fixedly arranged on the inner sleeve (2) along the circumferential direction; the driving component (3) is located on the clamp fixing outer sleeve (1) and is used to drive the inner sleeve (2) to slide axially, and to make the independent petals (21) expand and contract radially by means of the tapered pull-in shaft (11); the detection component (4) is located on the independent petals (21) and is used to detect the elastic properties of the independent petals (21).

2. The 18-lobed internal expansion lathe fixture according to claim 1, characterized in that: An end face protection plate (111) is fixedly provided on the side of the tapered pull-in shaft (11) away from the clamp fixing sleeve (1).

3. The 18-lobed internal expansion lathe fixture according to claim 1, characterized in that: The drive assembly (3) includes a drive plate (31), a sliding sleeve (32), and a connecting bolt (33). The drive plate (31) is slidably disposed inside the fixture fixing sleeve (1), and a hydraulic cylinder (311) is provided on one side. The hydraulic cylinder (311) is mounted on a lathe, and its telescopic end is fixedly connected to the drive plate (31). The sliding sleeve (32) passes through the fixture fixing sleeve (1), and its two ends abut against the drive plate (31) and the expansion inner sleeve (2) respectively. The connecting bolt (33) passes through the expansion inner sleeve (2), the fixture fixing sleeve (1), and the drive plate (31) in sequence, and is locked with a nut.

4. The 18-lobed internal expansion lathe fixture according to claim 3, characterized in that: The sliding sleeve (32) and the connecting bolt (33) are arranged in multiple sets at intervals along the circumference of the clamp fixing sleeve (1).

5. The 18-lobed internal expansion lathe fixture according to claim 2, characterized in that: Each independent flap (21) has a receiving groove (211) and an alignment groove (212) on both sides, with the receiving groove (211) and alignment groove (212) on two adjacent independent flaps (21) facing each other; the detection assembly (4) has multiple sets, each corresponding to one of the multiple independent flaps (21); the detection assembly (4) includes a detection telescopic rod (41), a mounting plate (42), an alignment block (43), a drive telescopic rod (44), and a connecting pipe (45); the detection... The telescopic rod (41) is located in the receiving groove (211), and its fixed end is fixedly connected to the independent flap (21). The rod-side cavity of the telescopic rod (41) is filled with liquid, and a return spring (411) is provided in the rodless cavity of the telescopic rod (41). The two ends of the return spring (411) are fixedly connected to the movable end of the telescopic rod (41) and the fixed end of the telescopic rod (41), respectively. The return spring (411) is in a compressed state. The mounting plate (42) is located in the alignment groove (212); the alignment block (43) is slidably disposed in the alignment groove (212), and one end abuts against the movable end of the detection telescopic rod (41). A drive spring (431) is provided on one side of the alignment block (43), and the two ends of the drive spring (431) are fixedly connected to the alignment block (43) and the mounting plate (42) respectively. The drive spring (431) is in a compressed state, and the preset elastic force is greater than that of the reset spring (41). 11) The preset elastic force; the driving telescopic rod (44) is located on the side of the independent petal (21) away from the expansion inner sleeve (2), and the fixed end is fixedly connected to the independent petal (21). The rodless cavity of the driving telescopic rod (44) is filled with liquid. A baffle (441) is fixedly provided on the movable end of the driving telescopic rod (44). The two ends of the connecting pipe (45) are respectively connected to the rod cavity of the detection telescopic rod (41) and the rodless cavity of the driving telescopic rod (44).

6. The 18-lobed internal expansion lathe fixture according to claim 5, characterized in that: The detection component (4) also includes an adjusting telescopic rod (46); the mounting plate (42) is slidably connected to the independent flap (21), and the rod cavity of the driving telescopic rod (44) is filled with liquid; the adjusting telescopic rod (46) is embedded in the side wall of the alignment groove (212), and the movable end is fixedly connected to the mounting plate (42); the rodless cavity of the adjusting telescopic rod (46) is filled with liquid; and the rodless cavity of the adjusting telescopic rod (46) and the rod cavity of the driving telescopic rod (44) are connected through a pipe.

7. The 18-lobed internal expansion lathe fixture according to claim 5, characterized in that: An adjustment component (5) is provided on the end face protective plate (111). The adjustment component (5) is used to prevent the baffle (441) from being accidentally extended due to slight deformation.

8. The 18-lobed internal expansion lathe fixture according to claim 7, characterized in that: The regulating assembly (5) includes a transfer box (51), a partition (52), an adjusting screw (53), and a connecting branch pipe (54); an overflow valve (451) is installed on the connecting pipe (45); the transfer box (51) is fixedly mounted on the end face protection plate (111); the partition (52) is slidably mounted inside the transfer box (51) and divides the transfer box (51) into a liquid accumulation chamber and an regulating chamber; the adjusting screw (53) is threaded into the transfer box (51) and one end abuts against the partition (52); both ends of the connecting branch pipe (54) are respectively connected to multiple connecting pipes (45) and the liquid accumulation chamber of the transfer box (51), and the connection between the connecting branch pipe (54) and the connecting pipe (45) is located between the overflow valve (451) and the detection telescopic rod (41).

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