Chuck inner hole grinding device

Abstract

The utility model discloses a chuck inner hole grinding device belongs to lathe auxiliary processing frock technical field. Including vertical lathe tool rest, tool rest connecting body, grinding head combination, power transmission subassembly and tension adjusting assembly, tool rest connecting body is fixed in vertical lathe tool rest bottom, the grinding head combination is fixed in tool rest connecting body one end bottom, the output of grinding head combination is fixed with grinding wheel, power transmission subassembly is installed on tool rest connecting body, and is set up in grinding head combination opposite side, power transmission subassembly includes drive motor, and the output shaft of drive motor is fixed with motor synchronous pulley, and motor synchronous pulley is connected with grinding head synchronous pulley sleeve through synchronous belt body, and grinding head synchronous pulley is fixed in the input of grinding head combination, the utility model discloses a chuck inner hole grinding device can be installed directly in vertical lathe tool rest bottom and completes inner hole grinding processing, effectively promotes processing precision and surface quality, and shortens processing cycle.

Description

Technical Field

[0001] This utility model specifically relates to a chuck inner hole grinding device, belonging to the field of lathe auxiliary machining tooling technology. Background Technology

[0002] In the field of heavy machine tool manufacturing and repair, the chuck inner hole of vertical lathes and heavy-duty horizontal lathes is usually finished by precision turning. Precision turning generally uses an internal grinding device, such as the deep hole grinding machine disclosed in Chinese Patent Publication No. CN121104788A. This structure, through the flexible adjustment capability of three sets of central supports, allows the support position to be optimized according to the shape and size of the part, further reducing the machining error caused by the irregular shape of the part and ensuring the machining accuracy of the entire machine tool. However, due to the inherent characteristics of the turning process, the surface roughness of the chuck inner hole after precision turning is difficult to meet the design requirements, resulting in chuck... The poor fit between the inner hole and the spindle inner hole directly affects the core machining accuracy of machined parts, such as straightness and cylindricity. Furthermore, these chucks are mostly made of cast steel, and casting defects such as sand holes, porosity, and shrinkage cavities are unavoidable during the casting process. These defects need to be repaired by welding during production. The uneven hardness of the welded area can easily cause tool deflection during precision turning. In actual production, the high points of the welded area are often manually ground with an angle grinder to assist in machining, which not only wastes manpower and resources but also significantly increases the machining cycle. Moreover, the machining quality is greatly affected by the operator's skill level, making it difficult to guarantee stability. Utility Model Content

[0003] To address the aforementioned issues, this invention proposes a chuck internal hole grinding device that can be directly installed at the bottom of a vertical lathe tool post to complete internal hole grinding, effectively improving machining accuracy and surface quality, and shortening the machining cycle.

[0004] The chuck internal hole grinding device of this utility model includes a vertical lathe tool post, and also includes: Tool holder connector, which is fixed to the bottom of the vertical lathe tool holder; the tool holder connector is fixed to the bottom of the vertical lathe tool holder and serves as the mounting and bearing component of the entire grinding device; A grinding head assembly is fixed to the bottom of one end of a tool holder connector. A grinding wheel is fixed to the output end of the grinding head assembly for completing grinding and cutting operations. A power transmission assembly is mounted on the tool holder connector and positioned on the opposite side of the grinding head assembly. The power transmission assembly includes a drive motor, the output shaft of which is fixed with a motor synchronous pulley. The motor synchronous pulley is connected to the grinding head synchronous pulley via a synchronous belt, and the grinding head synchronous pulley is fixed to the input end of the grinding head assembly. The tension adjustment assembly includes a sliding motor base plate with multiple sets of elongated holes along the tensioning direction of the synchronous belt; tension bolts are provided on the elongated holes and are fastened to the tool holder connector; the drive motor is fixed to the sliding motor base plate.

[0005] During operation, the drive motor outputs rotational power, driving the motor's synchronous pulley to rotate. This power is then transmitted to the grinding head's synchronous pulley via the synchronous belt, which in turn drives the output end of the grinding head assembly to rotate synchronously. This, in turn, drives the grinding wheel to rotate at high speed, achieving grinding and cutting. To adjust the tension of the synchronous belt, loosen the tensioning bolt and push the sliding motor base plate along the length of the elongated hole. This moves the entire drive motor, changing the center distance between the motor's synchronous pulley and the grinding head's synchronous pulley. Once the tension of the synchronous belt meets the requirements, tighten the tensioning bolt to complete the fixation. The entire grinding device can be directly mounted on the bottom of the vertical lathe tool post, utilizing the vertical lathe's own feed and chuck rotation to complete the grinding process. No dedicated grinding machine is required. The synchronous belt drive provides cushioning and shock absorption, reducing the direct transmission of drive motor vibration to the grinding wheel and ensuring grinding stability. The tensioning structure with the elongated hole and tensioning bolt is simple, reliable, easy to adjust, and highly efficient.

[0006] Furthermore, the grinding head assembly includes a long shaft, a sleeve body, a sleeve seat plate, and two sets of angular contact bearings; the sleeve body is fitted and fixed to the sleeve seat plate, and the sleeve seat plate is fixed to the tool holder connector; the long shaft is rotatably supported inside the sleeve body by the two sets of angular contact bearings, and the angular contact bearings are disposed at both ends of the sleeve body; one end of the long shaft extends out of the sleeve body and is fixedly installed with the grinding wheel, and the other end extends out of the sleeve body and is fixedly installed with the grinding head synchronous pulley.

[0007] When the grinding head assembly is working, the sleeve body is fixedly installed with the tool holder through the sleeve seat plate, providing a closed and stable support cavity for the long shaft; two sets of angular contact bearings are respectively arranged at both ends of the sleeve body, forming a double-support rotational support for the long shaft; the rotational power received by the grinding head synchronous belt pulley is transmitted axially to the grinding wheel end through the long shaft, driving the grinding wheel to rotate at high speed and stably; through the arrangement of the double-support angular contact bearings, the long shaft can bear both radial and axial forces at the same time, adapting to the load characteristics of grinding, and ensuring the rotational accuracy and operational stability of the long shaft.

[0008] Furthermore, bearing caps are fixed to both ends of the sleeve body by bolts, and the long shaft moves through the bearing caps; a bearing spacer is provided between the bearing caps and the angular contact bearing.

[0009] During operation, the bearing cap is bolted to the end of the sleeve body, and together with the bearing spacer, it forms an axial limit on the outer ring of the angular contact bearing, preventing axial movement of the bearing during operation. By replacing the bearing spacer with one of different thicknesses, the axial preload of the angular contact bearing can be adjusted, while avoiding direct contact between the bearing cap and the bearing outer ring, which could cause end face damage. Through the cooperation between the bearing cap and the bearing spacer, the installation preload of the angular contact bearing can be precisely controlled, ensuring the support rigidity and rotational accuracy of the angular contact bearing, while also facilitating the disassembly and replacement of the angular contact bearing, thus improving maintenance convenience.

[0010] Furthermore, a round nut is screwed onto one end of the long shaft where the grinding wheel is mounted, and one end of the round nut abuts against the inner ring of the angular contact bearing; a shoulder retaining ring is provided between the other end of the long shaft and the grinding wheel; a rear washer is provided at the end of the grinding wheel away from the shoulder retaining ring, and a first locking nut is screwed onto it; asbestos paper is placed on both sides of the grinding wheel.

[0011] During operation, the round nut abuts against the inner ring of the angular contact bearing from the inside, achieving axial positioning of the inner ring. The shoulder retaining ring provides an inner mounting and positioning surface for the grinding wheel. The rear washer is placed on the outside of the grinding wheel, and together with the tightening force of the first locking nut, clamps and fixes the grinding wheel between the shoulder retaining ring and the rear washer. Asbestos paper is placed on both sides of the grinding wheel to evenly distribute the clamping force and buffer vibration, preventing the grinding wheel from breaking due to hard contact with metal parts. The clamping structure using the round nut, shoulder retaining ring, rear washer, and first locking nut ensures that the grinding wheel is firmly and reliably clamped, and that disassembly and replacement are convenient. The asbestos paper on both sides effectively protects the grinding wheel, improves its operational stability, and extends its service life.

[0012] Furthermore, a pulley spacer is provided at one end of the grinding head synchronous pulley mounted on the long shaft. The pulley spacer abuts against the inner ring of the angular contact bearing and the grinding head synchronous pulley. A second locking nut is provided at the end of the grinding head synchronous pulley away from the pulley spacer. The second locking nut is screwed and fixed to the long shaft.

[0013] During operation, the pulley spacer is placed between the inner ring of the angular contact bearing and the grinding head synchronous pulley, which not only achieves axial positioning of the inner ring of the corresponding angular contact bearing, but also provides an inner mounting and positioning surface for the grinding head synchronous pulley. After the second locking nut is tightened, the grinding head synchronous pulley is clamped and fixed between the pulley spacer and the second locking nut, ensuring that there is no relative slippage between the grinding head synchronous pulley and the long shaft and that they rotate synchronously. Through the cooperation of the pulley spacer and the second locking nut, the grinding head synchronous pulley is accurately positioned and firmly connected, which can ensure the stability and transmission accuracy of the synchronous belt drive, while also facilitating the disassembly and replacement of the synchronous pulley.

[0014] Furthermore, it also includes felt, which is disposed between the round nut and the bearing cap, and between the pulley spacer and the bearing cap; the felt fills the gap between the bearing cap and the internal rotating parts, and the round nut and pulley spacer, which rotate synchronously with the long shaft, are tightly fitted with the end face of the felt to form a contact sealing structure; the felt can effectively prevent dust and metal chips generated during grinding from entering the sleeve body, avoid dust from entering the angular contact bearing and causing bearing wear and lubrication failure, extend the bearing service life, and improve the reliability and durability of the grinding head assembly.

[0015] Furthermore, the tool holder connector is a frame structure, with the grinding head assembly and the drive motor respectively mounted on opposite sides of the tool holder connector. The grinding head synchronous belt pulley passes through the internal space of the tool holder connector. The frame structure of the tool holder connector itself has high structural rigidity and damping performance. The grinding head assembly and the drive motor are positioned on opposite sides of the frame, and the synchronous belt passes through the internal space of the frame to achieve transmission. The frame structure of the tool holder connector can effectively isolate the vibration of the drive motor from being transmitted to the grinding head assembly, further improving the rotational stability of the grinding wheel and ensuring the surface quality of the grinding process. At the same time, the frame structure has a compact layout. It features high space utilization and strong load-bearing capacity. A synchronous belt cover is detachably installed on the tool holder connector, completely enclosing the motor synchronous pulley, synchronous belt body, and grinding head synchronous pulley. The synchronous belt cover is detachably fixed to the tool holder connector with bolts, completely enclosing the entire synchronous belt transmission mechanism and isolating it from the external environment and transmission components. The synchronous belt cover prevents grinding debris, oil, and other foreign objects from falling into the meshing surface of the synchronous belt body and pulley, avoiding transmission slippage and abnormal wear, and extending the service life of the synchronous belt body and pulley. Simultaneously, it isolates the safety hazards caused by exposed transmission components, improving the safety of the device operation.

[0016] Furthermore, an adjusting seat is fixed to the tool holder connector, and an adjusting screw is screwed onto the adjusting seat. The axis of the adjusting screw is parallel to the length direction of the elongated hole, and the end of the adjusting screw abuts against the end face of the sliding motor base plate away from the drive motor. The adjusting seat provides mounting support for the adjusting screw. When the adjusting screw is rotated, the adjusting screw feeds along its own axis, and the end pushes the sliding motor base plate to move smoothly along the direction of the elongated hole, realizing a fine-tuning of the tension of the synchronous belt. After adjustment, the tightening bolt is tightened to complete the fixation. Through the cooperation of the adjusting seat and the adjusting screw, the position of the sliding motor base plate can be precisely adjusted, avoiding the problem of excessive displacement caused by manual pushing. The tension of the synchronous belt is more accurately controlled. After adjustment, the tensioning bolt and the adjusting screw achieve bidirectional position locking.

[0017] Furthermore, the two sets of angular contact bearings are arranged back-to-back within the sleeve body; at least one set of adjusting shims is provided between the sleeve seat plate and the tool holder connector, the adjusting shim set being composed of multiple thin metal shims of different thicknesses stacked together. The back-to-back installation of the two sets of angular contact bearings, meaning the outer ring wide end faces of the two sets of angular contact bearings are positioned opposite each other, allows them to simultaneously withstand bidirectional axial and radial loads, resulting in stronger resistance to overturning moments. The adjusting shims are placed between the contact surfaces of the sleeve seat plate and the tool holder connector; by adding or removing thin metal shims of different thicknesses, the installation perpendicularity of the grinding head assembly can be adjusted, correcting the parallelism deviation between the long shaft and the chuck inner hole axis. The back-to-back angular contact bearings have stronger load-bearing capacity and higher operating rigidity, making them suitable for heavy-duty grinding conditions and improving grinding stability. The adjusting shims can precisely correct the installation posture of the grinding head assembly, ensuring the straightness of the grinding wheel feed and improving the dimensional and positional accuracy of internal hole grinding.

[0018] Furthermore, an annular sealing groove is provided on the inner side of the bearing cap, and the felt is embedded in the annular sealing groove, with the inner ring of the felt and the outer wall of the long shaft being interference-fitted to form a dynamic seal.

[0019] During operation, the annular sealing groove provides radial and axial restraint to the felt, preventing it from shifting and falling off as the long shaft rotates; the inner ring of the felt is press-fitted against the outer wall of the long shaft, forming a continuous contact dynamic seal, which completely prevents external dust and debris from intruding into the sleeve body.

[0020] Compared with the prior art, the chuck inner hole grinding device of this utility model has the following advantages: 1. It can be directly fixed to the bottom of the vertical lathe tool post. The grinding of the chuck inner hole can be completed by the feed motion of the vertical lathe and the rotation motion of the chuck. There is no need to purchase a special internal grinding machine, which greatly reduces the equipment cost. It is suitable for the finishing and repair of the chuck inner hole of vertical lathes and heavy-duty horizontal lathes.

[0021] 2. The synchronous belt drive combined with the frame-type tool holder connector uses a vibration isolation structure, which can effectively isolate the vibration of the drive motor from being transmitted to the grinding wheel. Combined with the stable support of double sets of back-to-back angular contact bearings, it significantly improves the grinding wheel rotation accuracy and grinding surface quality, meeting the roughness and positional accuracy requirements of the chuck inner hole.

[0022] 3. The tension adjustment assembly adopts a structure with long holes, tension bolts, and adjusting set screws for fine adjustment, making the tension adjustment of the synchronous belt convenient and precise, ensuring transmission stability while reducing the difficulty of assembly and adjustment.

[0023] 4. Equipped with multiple sealing and protective structures and protective covers, it effectively blocks grinding dust and foreign objects from entering, ensuring high operational reliability and long maintenance cycles. It can directly grind and repair weld defects in the inner hole of the chuck, completely replacing manual grinding operations, significantly improving processing efficiency, shortening the chuck processing cycle, and ensuring good processing quality consistency. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of one embodiment of the chuck inner hole grinding device of this utility model.

[0025] Figure 2 This is a schematic cross-sectional view of the grinding head assembly of this utility model.

[0026] Figure 3 This is a schematic diagram of another embodiment of the chuck inner hole grinding device of this utility model.

[0027] Reference numerals: 1. Vertical lathe tool post; 2. Tool post connector; 3. Grinding head assembly; 4. Grinding wheel; 5. Drive motor; 6. Motor timing pulley; 7. Timing belt; 8. Grinding head timing pulley; 9. Sliding motor base plate; 10. Long hole; 11. Long shaft; 12. Sleeve body; 13. Sleeve base plate; 14. Angular contact bearing; 15. Bearing cap; 16. Bearing spacer; 17. Round nut; 18. Shoulder retaining ring; 19. Rear washer; 20. First locking nut; 21. Pulley spacer; 22. Second locking nut; 23. Felt; 24. Adjusting seat; 25. Adjusting set screw. Detailed Implementation

[0028] Example: like Figures 1 to 3 The chuck internal hole grinding device shown includes a vertical lathe tool post 1, and also includes: Tool holder connector 2, which is fixed to the bottom of the vertical lathe tool holder 1; the tool holder connector 2 is fixed to the bottom of the vertical lathe tool holder 1 and serves as the mounting and bearing component of the entire grinding device; Grinding head assembly 3, which is fixed to the bottom of one end of tool holder connector 2, and a grinding wheel 4 is fixed to the output end of grinding head assembly 3 for completing grinding and cutting operations; A power transmission assembly is mounted on the tool holder connector 2 and is located on the opposite side of the grinding head assembly 3. The power transmission assembly includes a drive motor 5, and a motor synchronous pulley 6 is fixed to the output shaft of the drive motor 5. The motor synchronous pulley 6 is sleeved with the grinding head synchronous pulley 8 through a synchronous belt body 7. The grinding head synchronous pulley 8 is fixed to the input end of the grinding head assembly 3. The tension adjustment assembly includes a sliding motor base plate 9, which has multiple sets of elongated holes 10 along the tensioning direction of the synchronous belt body 7; tension bolts are provided on the elongated holes 10, and the tension bolts are fastened to the tool holder connecting body 2; the drive motor 5 is fixed on the sliding motor base plate 9.

[0029] During operation, the drive motor 5 outputs rotational power, driving the motor synchronous pulley 6 to rotate. The power is transmitted to the grinding head synchronous pulley 8 through the synchronous belt 7, which in turn drives the output end of the grinding head assembly 3 to rotate synchronously, thereby driving the grinding wheel 4 to rotate at high speed to achieve grinding and cutting. When adjusting the tension of the synchronous belt 7, loosen the tensioning bolt and push the sliding motor base plate 9 along the length of the elongated hole 10, causing the drive motor 5 to move as a whole, changing the center distance between the motor synchronous pulley 6 and the grinding head synchronous pulley 8. After the tension of the synchronous belt 7 meets the requirements, tighten the tensioning bolt to complete the fixation. The entire grinding device can be directly mounted on the bottom of the vertical lathe tool holder 1, and grinding is completed by the vertical lathe's own feed and chuck rotation. No special grinding machine is required. The synchronous belt 7 transmission can buffer and absorb shock, reducing the direct transmission of vibration from the drive motor 5 to the grinding wheel 4 and ensuring grinding stability. The tensioning structure of the elongated hole 10 and the tensioning bolt is simple and reliable, easy to adjust, and has high assembly and adjustment efficiency.

[0030] The grinding head assembly 3 includes a long shaft 11, a sleeve body 12, a sleeve base plate 13, and two sets of angular contact bearings 14. The sleeve body 12 is fitted and fixed on the sleeve base plate 13, and the sleeve base plate 13 is fixed on the tool holder connector 2. The long shaft 11 is rotatably supported inside the sleeve body 12 by the two sets of angular contact bearings 14, and the angular contact bearings 14 are disposed at both ends inside the sleeve body 12. One end of the long shaft 11 extends out of the sleeve body 12 and is fixedly installed with the grinding wheel 4, and the other end extends out of the sleeve body 12 and is fixedly installed with the grinding head synchronous pulley 8.

[0031] When the grinding head assembly 3 is working, the sleeve body 12 is fixedly installed with the tool holder connector 2 through the sleeve seat plate 13, providing a closed and stable support cavity for the long shaft 11; two sets of angular contact bearings 14 are respectively arranged at both ends inside the sleeve body 12, forming a double-support rotational support for the long shaft 11; the rotational power received by the grinding head synchronous pulley 8 is axially transmitted to the grinding wheel 4 through the long shaft 11, driving the grinding wheel 4 to rotate at high speed and stably; through the arrangement of the double-support angular contact bearings 14, the long shaft 11 can bear both radial and axial forces at the same time, adapting to the load characteristics of grinding, and ensuring the rotational accuracy and operational stability of the long shaft 11.

[0032] The sleeve body 12 is fixed to bearing caps 15 by bolts at both ends, and the long shaft 11 moves through the bearing caps 15; a bearing spacer 16 is provided between the bearing caps 15 and the angular contact bearing 14.

[0033] During operation, the bearing cap 15 is fastened to the end of the sleeve body 12 with bolts, and works with the bearing spacer 16 to axially limit the outer ring of the angular contact bearing 14, preventing axial movement of the bearing during operation. By replacing the bearing spacer 16 with different thicknesses, the axial preload of the angular contact bearing 14 can be adjusted, while avoiding direct contact between the bearing cap 15 and the outer ring of the angular contact bearing 14, which could cause end face damage. Through the cooperation of the bearing cap 15 and the bearing spacer 16, the installation preload of the angular contact bearing 14 can be precisely controlled, ensuring the support rigidity and rotational accuracy of the angular contact bearing 14, while facilitating the disassembly and replacement of the angular contact bearing 14 and improving maintenance convenience.

[0034] A round nut 17 is screwed onto one end of the long shaft 11 where the grinding wheel 4 is mounted. One end of the round nut 17 abuts against the inner ring of the angular contact bearing 14. A shoulder retaining ring 18 is provided between the other end of the long shaft 11 and the grinding wheel 4. A rear washer 19 is provided on the end of the grinding wheel 4 away from the shoulder retaining ring 18, and a first locking nut 20 is screwed onto it. Asbestos paper is placed on both sides of the grinding wheel 4.

[0035] During operation, the round nut 17 abuts against the inner ring of the angular contact bearing 14 from the inside, achieving axial positioning of the inner ring of the angular contact bearing 14; the shoulder retaining ring 18 provides an inner mounting and positioning surface for the grinding wheel 4; the rear washer 19 is placed on the outside of the grinding wheel 4, and with the tightening force of the first locking nut 20, clamps and fixes the grinding wheel 4 between the shoulder retaining ring 18 and the rear washer 19; asbestos paper is placed on both sides of the grinding wheel 4 to evenly distribute the clamping force and at the same time buffer vibration, preventing the grinding wheel 4 from breaking due to hard contact with metal parts; the clamping structure of the round nut 17, the shoulder retaining ring 18, the rear washer 19 and the first locking nut 20 ensures that the grinding wheel 4 is firmly and reliably clamped, and the disassembly and replacement operation is convenient; the asbestos paper on both sides can effectively protect the grinding wheel 4, improve the running stability of the grinding wheel 4, and extend the service life of the grinding wheel 4.

[0036] The long shaft 11 is provided with a pulley spacer 21 at one end where the grinding head synchronous pulley 8 is mounted. The pulley spacer 21 abuts against the inner ring of the angular contact bearing 14 and the grinding head synchronous pulley 8. A second locking nut 22 is provided at the end of the grinding head synchronous pulley 8 away from the pulley spacer 21. The second locking nut 22 is screwed and fixed to the long shaft 11. During operation, the pulley spacer 21 is placed between the inner ring of the angular contact bearing 14 and the grinding head synchronous pulley 8, which not only achieves axial positioning of the inner ring of the corresponding side angular contact bearing 14, but also provides an inner mounting and positioning surface for the grinding head synchronous pulley 8. After the second locking nut 22 is tightened, the grinding head synchronous pulley 8 is clamped and fixed between the pulley spacer 21 and the second locking nut 22, ensuring that the grinding head synchronous pulley 8 and the long shaft 11 have no relative sliding and rotate synchronously. Through the cooperation of the pulley spacer 21 and the second locking nut 22, the grinding head synchronous pulley 8 is accurately positioned and firmly connected, which can ensure the stability and transmission accuracy of the synchronous belt 7, and at the same time facilitate the disassembly and replacement of the synchronous pulley.

[0037] It also includes a felt 23, which is disposed between the round nut 17 and the bearing cap 15, and between the pulley spacer 21 and the bearing cap 15. The felt 23 fills the gap between the bearing cap 15 and the internal rotating parts. The round nut 17 and the pulley spacer 21, which rotate synchronously with the long shaft 11, are in close contact with the end face of the felt 23 to form a contact sealing structure. The felt 23 can effectively prevent dust and metal chips generated during grinding from entering the sleeve body 12, avoid dust from entering the angular contact bearing 14 and causing bearing wear and lubrication failure, extend the service life of the bearing 11, and improve the reliability and durability of the grinding head assembly 3.

[0038] The tool holder connector 2 has a frame structure. The grinding head assembly 3 and the drive motor 5 are respectively installed on opposite sides of the tool holder connector 2. The grinding head synchronous pulley 8 passes through the internal space of the tool holder connector 2. The frame structure of the tool holder connector 2 has high structural rigidity and damping performance. The grinding head assembly 3 and the drive motor 5 are located on opposite sides of the frame, and the synchronous belt 7 passes through the internal space of the frame to achieve transmission. The frame structure of the tool holder connector 2 can effectively isolate the vibration of the drive motor 5 from being transmitted to the grinding head assembly 3, further improving the rotational stability of the grinding wheel 4 and ensuring the surface quality of the grinding process. At the same time, the frame structure has a compact layout. It features high space utilization and strong load-bearing capacity. A synchronous belt cover is detachably installed on the tool holder connecting body 2, which covers the outside of the motor synchronous pulley 6, the synchronous belt body 7, and the grinding head synchronous pulley 8. The synchronous belt cover is detachably fixed to the tool holder connecting body 2 with bolts, completely enclosing the entire synchronous belt transmission mechanism and isolating it from the external environment and transmission components. The synchronous belt cover can prevent grinding debris, oil, and other foreign objects from falling into the meshing surface of the synchronous belt body 7 and the pulley, avoiding transmission slippage and abnormal wear, and extending the service life of the synchronous belt body 7 and the pulley. At the same time, it can isolate the safety hazards caused by exposed transmission components and improve the safety of the device operation.

[0039] like Figure 3 As shown, an adjusting seat 24 is also fixed on the tool holder connecting body 2. An adjusting screw 25 is screwed onto the adjusting seat 24. The axis of the adjusting screw 25 is parallel to the length direction of the elongated hole 10, and the end of the adjusting screw 25 abuts against the end face of the sliding motor base plate 9 away from the drive motor 5. The adjusting seat 24 provides mounting support for the adjusting screw 25. When the adjusting screw 25 is rotated, the adjusting screw 25 feeds along its own axis, and the end pushes the sliding motor base plate 9 to move smoothly along the direction of the elongated hole 10, realizing a small and precise adjustment of the tension of the synchronous belt 7. After adjustment, the tightening bolt is tightened to complete the fixation. Through the cooperation of the adjusting seat 24 and the adjusting screw 25, the position of the sliding motor base plate 9 can be precisely adjusted, avoiding the problem of excessive displacement caused by manual pushing. The tension of the synchronous belt 7 is more precisely controlled. After adjustment, the tensioning bolt and the adjusting screw 25 are used to achieve bidirectional position locking.

[0040] Two sets of angular contact bearings 14 are arranged back-to-back inside the sleeve body 12. At least one set of adjusting shims is provided between the sleeve seat plate 13 and the tool holder connecting body 2. The adjusting shim set is composed of multiple thin metal shims of different thicknesses stacked together. The two sets of angular contact bearings 14 are installed back-to-back, that is, the outer ring wide end faces of the two sets of angular contact bearings 14 are arranged opposite each other, which can simultaneously bear bidirectional axial load and radial load, and have stronger anti-overturning moment capability. The adjusting shim set is placed between the contact surfaces of the sleeve seat plate 13 and the tool holder connecting body 2. By adding or removing thin metal shims of different thicknesses, the installation perpendicularity of the grinding head assembly 3 can be adjusted, and the parallelism deviation between the long shaft 11 and the chuck inner hole axis can be corrected. The back-to-back angular contact bearings 14 have stronger load-bearing capacity and higher operating rigidity, which can be adapted to heavy-duty grinding conditions and improve grinding stability. The adjusting shim set can accurately correct the installation posture of the grinding head assembly 3, ensure the straightness of the grinding wheel 4 feed, and improve the form and position accuracy of the inner hole grinding.

[0041] The bearing cap 15 has an annular sealing groove on its inner side. The felt 23 is embedded in the annular sealing groove, and the inner ring of the felt 23 is press-fitted with the outer wall of the long shaft 11 to form a dynamic seal.

[0042] During operation, the annular sealing groove provides radial and axial restraint to the felt 23, preventing it from shifting and falling off as the long shaft 11 rotates; the inner ring of the felt 23 is press-fitted to the outer wall of the long shaft 11, forming a continuous contact dynamic seal, which completely prevents external dust and debris from entering the sleeve body 12.

[0043] The working process of the chuck internal hole grinding device in this embodiment is as follows: The first step is the assembly and installation of the device: the internal assembly of the grinding head assembly 3 is completed in advance, and the two sets of angular contact bearings 14, bearing spacers 16, bearing caps 15, long shafts 11, sealing felt 23 and other components are installed into the sleeve body 12 to complete the clamping of the grinding wheel 4 and the synchronous belt pulley 8 of the grinding head; then the sleeve base plate 13 is fixed to the bottom of the tool holder connecting body 2 with the adjusting shim set, the drive motor 5 is fixed to the sliding motor base plate 9, the synchronous belt body 7 is fitted and the synchronous belt cover is installed; finally, the tool holder connecting body 2 is hoisted and aligned to the bottom of the vertical lathe tool holder 1 and fixed by tightening the bolts. The second step is tension adjustment: loosen all tension bolts, rotate the adjusting screw 25 to push the sliding motor base plate 9 to move horizontally, fine adjust the tension of the synchronous belt body 7, and after confirming that the tension meets the transmission requirements, tighten all tension bolts to complete the positioning. The third step is the grinding operation: Start the drive motor 5, which drives the synchronous pulley 6 to rotate. The synchronous belt 7 drives the synchronous pulley 8 of the grinding head to rotate synchronously, which in turn drives the long shaft 11 and the grinding wheel 4 to rotate at high speed and stably. Operate the vertical lathe tool post 1 to slowly descend, driving the grinding wheel 4 to extend into the inner hole of the chuck to be processed, so that the outer circle of the grinding wheel 4 makes slight contact with the inner wall of the chuck hole. Keep the grinding wheel 4 rotating at high speed, operate the vertical lathe chuck to drive the workpiece to rotate at low speed, and at the same time control the vertical lathe tool post 1 to drive the grinding wheel 4 to feed at a uniform speed along the chuck axis to complete the full surface grinding and finishing of the inner hole of the chuck. For areas with welding defects, control the tool post to drive the grinding wheel 4 to perform targeted reciprocating grinding and dressing until the defective area is flush with the inner hole base surface and the roughness meets the standard. Step 4, finishing the machining: After grinding is completed, stop the drive motor 5 and operate the vertical lathe tool post 1 to drive the grinding wheel 4 to rise and exit the chuck inner hole; regularly check the tension of the timing belt 7 and the sealing status of the felt 23, and replace it in time when it is worn.

[0044] During the machining process, the two sets of back-to-back angular contact bearings 14 simultaneously bear the radial load and bidirectional axial load generated by grinding, providing strong anti-overturning capability and ensuring the rotational accuracy of the long shaft 11; the synchronous belt 7 can absorb part of the vibration of the drive motor 5, and together with the vibration isolation effect of the frame-type tool holder connector 2, it significantly reduces the amount of vibration transmitted to the grinding wheel 4, ensuring the surface roughness quality of the ground surface; the felt 23 in the annular sealing groove continuously prevents grinding dust from entering the bearing interior, and the synchronous belt cover isolates external foreign objects, jointly ensuring the long-term stable operation of the device.

[0045] The above embodiments are merely preferred embodiments of the present utility model. Therefore, all equivalent changes or modifications made to the structure, features and principles described in the claims of the present utility model are included within the scope of the present utility model.

Claims

1. A chuck internal hole grinding device, comprising a vertical lathe tool post, characterized in that, Also includes: Tool holder connector, which is fixed to the bottom of the vertical lathe tool holder; A grinding head assembly is fixed to the bottom of one end of a tool holder connector, and a grinding wheel is fixed to the output end of the grinding head assembly. A power transmission assembly is mounted on the tool holder connector and positioned on the opposite side of the grinding head assembly. The power transmission assembly includes a drive motor, the output shaft of which is fixed with a motor synchronous pulley. The motor synchronous pulley is connected to the grinding head synchronous pulley via a synchronous belt, and the grinding head synchronous pulley is fixed to the input end of the grinding head assembly. The tension adjustment assembly includes a sliding motor base plate with multiple sets of elongated holes along the tensioning direction of the synchronous belt; tension bolts are provided on the elongated holes and are fastened to the tool holder connector; the drive motor is fixed to the sliding motor base plate.

2. The chuck internal hole grinding device according to claim 1, characterized in that: The grinding head assembly includes a long shaft, a sleeve body, a sleeve base plate, and two sets of angular contact bearings; the sleeve body is fitted and fixed to the sleeve base plate, and the sleeve base plate is fixed to the tool holder connector; the long shaft is rotatably supported inside the sleeve body by the two sets of angular contact bearings, and the angular contact bearings are located at both ends of the sleeve body; one end of the long shaft extends out of the sleeve body and is fixedly installed with the grinding wheel, and the other end extends out of the sleeve body and is fixedly installed with the grinding head synchronous pulley.

3. The chuck internal hole grinding device according to claim 2, characterized in that, The sleeve body is fixed to bearing caps at both ends by bolts, and the long shaft moves through the bearing caps; a bearing spacer is provided between the bearing caps and the angular contact bearing.

4. The chuck internal hole grinding apparatus according to claim 3, characterized in that, A round nut is screwed onto one end of the long shaft where the grinding wheel is mounted, and one end of the round nut abuts against the inner ring of the angular contact bearing; a shoulder retaining ring is provided between the other end of the long shaft and the grinding wheel; a rear washer is provided at the end of the grinding wheel away from the shoulder retaining ring, and a first locking nut is screwed onto it; asbestos paper is placed on both sides of the grinding wheel.

5. The chuck internal hole grinding apparatus according to claim 3, characterized in that, A belt pulley spacer is provided at one end of the grinding head synchronous pulley mounted on the long shaft. The belt pulley spacer abuts against the inner ring of the angular contact bearing and the grinding head synchronous pulley. A second locking nut is provided at the end of the grinding head synchronous pulley away from the belt pulley spacer. The second locking nut is screwed and fixed to the long shaft.

6. The chuck internal hole grinding apparatus according to claim 4 or 5, characterized in that, It also includes felt, which is disposed between the round nut and the bearing cap, and between the pulley spacer and the bearing cap.

7. The chuck internal hole grinding apparatus according to claim 1, characterized in that, The tool holder connector is a frame structure. The grinding head assembly and the drive motor are respectively installed on opposite sides of the tool holder connector. The grinding head timing pulley passes through the internal space of the tool holder connector. A timing belt cover is detachably installed on the tool holder connector. The timing belt cover is entirely covered on the outside of the motor timing pulley, the timing belt body, and the grinding head timing pulley.

8. The chuck internal hole grinding apparatus according to claim 1, characterized in that, An adjusting seat is also fixed on the tool holder connector. An adjusting screw is screwed onto the adjusting seat. The axis of the adjusting screw is parallel to the length direction of the long hole, and the end of the adjusting screw abuts against the end face of the sliding motor base plate away from the drive motor.

9. The chuck internal hole grinding apparatus according to claim 2, characterized in that, The two sets of angular contact bearings are arranged back-to-back in the sleeve body; at least one set of adjusting shims is provided between the sleeve seat plate and the tool holder connector, and the adjusting shim set is composed of multiple thin metal shims of different thicknesses stacked together.

10. The chuck internal hole grinding apparatus according to claim 6, characterized in that, The bearing cap has an annular sealing groove on its inner side, and the felt is embedded in the annular sealing groove. The inner ring of the felt is press-fitted with the outer wall of the long shaft to form a dynamic seal.

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