Numerically controlled machine tool with locking guard

Abstract

The application discloses a numerical control machine tool with locking protection, which comprises a rack, a rotating chuck assembly located in the rack, the rotating chuck comprises a plurality of inner oil cylinders arranged in a ring shape, a piston block is arranged in the inner oil cylinder, a first connecting column is welded and fixed at one end of the piston block, a chuck is welded and fixed at the other end of the first connecting column and penetrates out of the inner oil cylinder, the pressure loss protection assembly comprises an outer cylinder body sleeved on the inner oil cylinder, a closed annular cavity is formed between the inner wall of the outer cylinder body and the outer wall of the inner oil cylinder, the piston ring separates the annular cavity into two chambers filled with hydraulic oil, the self-locking assembly is connected with the valve rod on the valve body through a connecting rod, and the self-locking assembly is used for locking and unlocking the valve body. The application can fundamentally solve the safety problem of workpiece flying out after pressure loss by assisting in maintaining the clamping tension through the closed annular locking cavity.

Description

Technical Field

[0001] This invention relates to the field of CNC machine tool technology, and more specifically, to a CNC machine tool with locking protection. Background Technology

[0002] When performing metal cutting operations such as turning on CNC machine tools, the workpiece is usually clamped by a chuck, and the spindle drives the chuck and workpiece to rotate at high speed. Hydraulic chucks have advantages such as large clamping force, fast operating speed, and ease of automatic control, and are therefore widely used in CNC machine tools.

[0003] The clamping state of a hydraulic chuck typically relies on the continuous pressure provided by the hydraulic system. During machine tool operation, when the hydraulic system loses pressure due to factors such as hydraulic line rupture, hydraulic pump failure, rotary joint seal failure, or power supply abnormalities, the hydraulic pressure acting on the chuck clamping mechanism will decrease, potentially causing the chuck to loosen. Since the workpiece rotates at high speed during machining, there is a risk of it slipping or even flying out if it loses reliable clamping. Therefore, maintaining the chuck's clamping state after an abnormal loss of pressure in the main hydraulic system is a crucial issue that needs to be addressed for the safety protection of hydraulic chucks.

[0004] To address the aforementioned issues, existing technologies typically employ accumulators, hydraulically controlled check valves, or mechanical locking mechanisms for pressure loss protection. While accumulators can continue to provide pressure for a certain period after the main hydraulic system loses pressure, their capacity to store hydraulic fluid and energy is limited. The pressure-holding time is also affected by factors such as accumulator capacity and system sealing performance, making it difficult to maintain a clamped state even in the event of complete hydraulic system failure.

[0005] Using hydraulically controlled check valves or other valves to seal off the oil circuit can also achieve pressure maintenance to a certain extent. However, these types of lock-up valves are usually located in the main hydraulic circuit, and their protective effect is still affected by the sealing status of the cylinders, rotary joints, and internal pipelines downstream of the lock-up valve. When leakage occurs downstream of the lock-up valve, the clamping mechanism may still experience a pressure drop, making it difficult to provide relatively independent pressure loss protection for the clamping actuators.

[0006] Furthermore, the rotary chuck needs to rotate at high speed with the spindle during operation. When using solenoid valves or other electrical actuators to control the rotating side locking mechanism, a power transmission structure such as a conductive slip ring is usually required between the stationary and rotating parts of the machine tool. This dynamic-static connection structure not only increases the structural complexity of the chuck system, but also makes it susceptible to wear, vibration, and changes in contact conditions during long-term high-speed rotation, increasing the likelihood of equipment failure and maintenance.

[0007] While some existing mechanical locking structures can reduce continuous reliance on hydraulic pressure, their locking mechanisms still need to ensure reliable locking and rapid unlocking during high-speed rotation. When the locking method mainly relies on friction, the locking performance is easily affected by vibration and changes in contact conditions. On the other hand, using a more complex mechanical clamping mechanism may affect the response speed and automation level of the chuck clamping and releasing actions, making it difficult to balance pressure loss safety protection, high-speed operation reliability, and continuous machining efficiency of CNC machine tools.

[0008] Therefore, there is still room for improvement in the existing hydraulic chuck pressure loss protection technology of CNC machine tools. It is necessary to provide a CNC machine tool that can maintain the workpiece clamping state when the main hydraulic system experiences abnormal pressure loss, adapt to the high-speed rotation of the chuck, and reduce the electrical connection structure on the rotating side to achieve reliable locking and unlocking. Summary of the Invention

[0009] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0010] Therefore, the object of the present invention is to provide a CNC machine tool with locking protection, including a frame and a rotary chuck assembly located within the frame.

[0011] It also includes a pressure loss protection component and a self-locking component that rotate synchronously with the rotary chuck assembly, and a spindle for driving the rotary chuck assembly to rotate.

[0012] The rotary chuck includes multiple inner oil cylinders arranged in a ring. A piston block is provided inside the inner oil cylinder. A first connecting post is welded and fixed to one end of the piston block. The other end of the first connecting post extends out of the inner oil cylinder and is welded and fixed to a chuck.

[0013] The pressure loss protection assembly includes an outer cylinder sleeved on an inner oil cylinder. The inner wall of the outer cylinder and the outer wall of the inner oil cylinder enclose a sealed annular cavity. A piston ring that moves synchronously with the piston block is provided in the annular cavity. The piston ring divides the annular cavity into two chambers filled with hydraulic oil. The outer cylinder walls of the two chambers are welded and connected to connecting pipes. The two connecting pipes are sealed to the valve body flange.

[0014] The self-locking assembly is connected to the valve stem on the valve body via a connecting rod, and the self-locking assembly is used to lock and unlock the valve body.

[0015] As a preferred technical solution: As described above, a CNC machine tool with locking protection is provided in the frame, and a tailstock sleeve that cooperates with the rotary chuck assembly is provided between the rotary chuck assembly and the tailstock sleeve for placing the cutting tool.

[0016] Through the above technical solution, the frame is equipped with a linear screw mechanism for driving the tailstock sleeve and the tool holder to move laterally, and a linear screw mechanism for driving the tool holder to move longitudinally, thereby realizing the feed motion of the tailstock sleeve and the tool.

[0017] The CNC machine tool with locking protection as described above further includes an oil circuit assembly for conveying oil to an inner oil cylinder, the oil circuit assembly including a hydraulic oil pipe, a rotary cylinder and an internal oil pipe.

[0018] The frame is connected to the bearing of the rotary cylinder. One end of the rotary cylinder is connected to the hydraulic oil pipe through a sealed rotary joint. The other end of the rotary cylinder is welded to the built-in oil pipe. The rotary cylinder is fixedly connected to one end of the main shaft through a flange.

[0019] The built-in oil pipe is located inside the main shaft, and one end of the built-in oil pipe is welded and fixed to the rotary cylinder and connected to it.

[0020] Through the above technical solution, the hydraulic oil pipe is connected to the hydraulic station, and the hydraulic oil pipe, rotary cylinder and spindle are coaxial. In this way, the rotary cylinder and spindle can rotate synchronously and smoothly, ensuring smooth oil transmission, while driving the workpiece to rotate at high speed by driving the chuck.

[0021] As described above, in a CNC machine tool with locking protection, the rotary chuck assembly further includes a hollow oil guide ring and an annular connecting seat. One end of the built-in oil pipe is closed and passes through the connecting seat. The closed end of the built-in oil pipe is connected to the oil guide ring through multiple oil guide pipes. The top end of the inner oil cylinder is open, and the top end of the inner oil cylinder is welded and fixed to the inner circular wall of the oil guide ring and connected to it.

[0022] The connecting seat is fixedly connected to the flange at one end of the main shaft. The connecting seat is welded to the outer circular wall of the chuck and the inner circular wall of the oil guide ring. The oil guide pipe is located between the connecting seat and the chuck.

[0023] Through the above technical solution, the two ends of the oil guide pipe are welded to the built-in oil pipe and the oil guide ring, which improves the overall sealing performance. One end of the built-in oil pipe is sealed to ensure that the internal oil can enter the oil guide ring through the oil guide pipe.

[0024] As described above, in a CNC machine tool with locking protection, a set of second connecting posts are welded and fixed on the piston ring. One end of the second connecting post penetrates the outer cylinder and is welded and fixed to the collar. The collar is sleeved and fixed on the first connecting post.

[0025] With the above technical solution, both the inner and outer circles of the piston ring are provided with polytetrafluoroethylene sealing gaskets, which achieve a sealing fit with the outer wall of the inner oil cylinder and with the inner wall of the outer cylinder.

[0026] As described above, a CNC machine tool with locking protection includes a fixed cylinder and a movable block located inside the fixed cylinder. The fixed cylinder has a connecting seat and a chuck passing through both ends. One end of the movable block is fixedly connected to a connecting rod, and the other end of the movable block has a groove. A movable piece is provided inside the groove. A magnet is embedded on the outer side of the movable piece. A guide post is welded and fixed at the center of the inner side of the movable piece. A guide groove for inserting the guide post is provided at the bottom of the groove. A first spring is sleeved on the guide post. Both ends of the first spring are welded to the guide post and the bottom of the groove.

[0027] With the above technical solution, the opening of the groove is smaller than the size of the movable piece, which can prevent the movable piece from falling out of the groove and ensure that the movable piece can pull the movable block to move synchronously when magnetic attraction occurs.

[0028] As described above, in a CNC machine tool with locking protection, the inner diameter of the fixed cylinder is the same as the outer diameter of the movable block, a set of symmetrically distributed slots are provided on the inner wall of the fixed cylinder, and a set of symmetrically distributed pin holes are provided on the outer wall of the movable block, with the bottom end of the pin hole communicating with the groove.

[0029] A movable pin is inserted into the slot, and the top of the movable pin is connected to the bottom of the slot via a second spring.

[0030] With the above technical solution, there is a step at the connection between the pin hole and the groove. When the fixing pin is inserted into the pin hole, the end of the fixing pin will abut against the step, thus preventing the fixing pin from being inserted into the groove and obstructing the movement of the magnet column.

[0031] As described above, in a CNC machine tool with locking protection, the axes of the slot and the pin hole are both inclined, the inclination angles of the slot and the pin hole are the same, and the inner diameters of the slot and the pin hole are the same.

[0032] By adopting the above technical solution and using an inclined setting, the component of the centrifugal force generated when the chuck rotates in the sliding direction of the fixed pin is attenuated by the tilt angle, which effectively reduces the risk of the fixed pin being thrown out of the slot by centrifugal force under high-speed rotation conditions.

[0033] As described above, in a CNC machine tool with locking protection, a set of symmetrically distributed magnetic columns are welded and fixed to the inner side of the movable plate. The top of the magnetic column is an inclined surface, and a magnetic block is embedded at the bottom of the movable pin. The top of the magnetic column and the surface of the magnetic block are magnetic poles of the same name.

[0034] With the above technical solution, when the fixing pin is inserted into the pin hole, and the top of the magnet moves below the bottom of the fixing pin, the angled top of the magnet causes the repulsive force between the magnet and the magnet to be exactly on the axis of the fixing pin. This allows the fixing pin to be quickly moved into the slot. As described above, in a CNC machine tool with locking protection, a rotating ring is connected to the frame bearing on one side of the connecting seat. The rotating ring has multiple notches, and a movable strip is inserted into the notch. An electromagnet is installed on the movable strip, and the electromagnet is coaxial with the fixed cylinder.

[0035] With the above technical solution, the movable bar is set in the recess in a detachable manner, such as by using bolts. This enables a modular design. When the electromagnet malfunctions and needs to be unlocked, there is no need to disassemble the chuck, clamp, or other components. The movable bar can be directly inserted and removed to replace the electromagnet. The maintenance process is simple, which greatly shortens downtime and reduces production and maintenance costs.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects: (1) In this invention, an outer cylinder is fitted onto an inner cylinder. After clamping, the hydraulic medium in the chambers on both sides of the piston ring is incompressible, and the piston ring is locked by the hydraulic medium on both sides and cannot move. The clamping force of the chuck can be maintained for a long time and is not affected by the failure of the main hydraulic system. Even if the upstream main oil circuit is broken or the rotary joint seal fails, resulting in the complete loss of the main clamping force, the closed annular locking cavity can still maintain the clamping force independently, which can fundamentally solve the safety problem of the workpiece flying out after the pressure is lost.

[0037] (2) The present invention is equipped with an electromagnet, and the electromagnet is installed on the rotatable ring on the stationary side of the machine tool. The rotatable ring has no physical contact with the rotating chuck. Non-contact triggering locking and unlocking is achieved by relying on magnetic force. There are no electrical components on the rotating parts, which completely eliminates complex dynamic and static transition parts such as conductive slip rings. The structure is simpler, the reliability is higher under high-speed rotation, and the failure rate is greatly reduced.

[0038] (3) The present invention adopts a self-locking method in which the spring drives the fixed pin to engage with the pin hole, replacing the traditional friction self-locking. In the locked state, the pin body relies on the shear bearing capacity to bear the axial load, and is not affected by cutting vibration, lubrication state of the contact surface, or temperature changes. The locking force is stable and has no attenuation, and the impact and vibration resistance is greatly improved.

[0039] (4) The clamping action of the chuck of the present invention is synchronized with the movement of the piston ring. After clamping is completed, it means that the closed chambers on both sides of the piston ring have been established. No additional sensors or control logic are needed to trigger it, which simplifies the system structure, improves the response speed, and the fixing pin is automatically inserted into the pin hole and removed from the pin hole by elastic force and magnetic force. The entire locking and unlocking action is fast and reliable, which can better adapt to efficient production. Attached Figure Description

[0040] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This is an external perspective view of the present invention; Figure 2 This is an internal perspective view of the present invention; Figure 3 This is an internal perspective view of the present invention; Figure 4 This is a perspective view of the spindle, hydraulic oil pipes, and rotary cylinder of the present invention. Figure 5 This is a perspective view of the oil guide ring and oil guide tube of the present invention; Figure 6 This is a perspective view of the oil guide ring and outer cylinder of the present invention; Figure 7 This is a perspective view of the outer cylinder, movable block, and fixed cylinder of the present invention; Figure 8 This is an exploded perspective view of the movable block and movable piece of the present invention; Figure 9 This is a perspective sectional view of the inner oil cylinder and outer cylinder of the present invention; Figure 10 This is a perspective sectional view of the movable block and the fixed cylinder of the present invention; Figure 11 This is a perspective view of the rotating ring and movable bar of the present invention.

[0041] In the diagram: 1. Frame; 2. Tailstock sleeve; 3. Tool holder; 4. Spindle; 5. Hydraulic oil pipe; 6. Rotary cylinder; 7. Internal oil pipe; 8. Guide ring; 9. Guide pipe; 10. Connecting seat; 11. Chuck; 12. Collet; 13. Inner oil cylinder; 14. Piston block; 15. First connecting column; 16. Outer cylinder; 17. Piston ring; 18. Connecting pipe; 19. Second connecting column; 20. Collar; 21. Valve body; 22. Connecting rod; 23. Movable block; 24. Fixed cylinder; 25. Groove; 26. Movable plate; 27. Magnet plate; 28. Guide column; 29. ​​First spring; 30. Pin hole; 31. Magnet column; 32. Hole groove; 33. Movable pin; 34. Second spring; 35. Rotating ring; 36. Movable bar; 37. Electromagnet. Detailed Implementation

[0042] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0043] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0044] like Figures 1-11 As shown, this embodiment of the invention discloses a CNC machine tool with locking protection, including a frame 1, a rotary chuck assembly located in the frame 1, and a tailstock sleeve 2 that cooperates with the rotary chuck assembly. A tool holder 3 for placing a tool is provided between the rotary chuck assembly and the tailstock sleeve 2.

[0045] It also includes a pressure loss protection component and a self-locking component that rotate synchronously with the rotary chuck assembly, and a spindle 4 for driving the rotary chuck assembly to rotate.

[0046] The rotary chuck includes multiple inner oil cylinders 13 arranged in a ring. A piston block 14 is provided inside the inner oil cylinder 13. A first connecting post 15 is welded and fixed to one end of the piston block 14. The other end of the first connecting post 15 passes through the inner oil cylinder 13 and is welded and fixed to a chuck 12.

[0047] The pressure loss protection assembly includes an outer cylinder 16 sleeved on the inner oil cylinder 13. The inner wall of the outer cylinder 16 and the outer wall of the inner oil cylinder 13 form a sealed annular cavity. A piston ring 17 that moves synchronously with the piston block 14 is provided in the annular cavity. A set of second connecting posts 19 are welded and fixed on the piston ring 17. One end of the second connecting post 19 passes through the outer cylinder 16 and is welded and fixed to the collar 20. The collar 20 is sleeved and fixed on the first connecting post 15.

[0048] Piston ring 17 divides the annular cavity into two chambers filled with hydraulic oil. The outer cylinder 16 of each chamber is welded to a connecting pipe 18, and the two connecting pipes 18 are sealed to the flange of valve body 21. The self-locking assembly is connected to the valve stem on the valve body 21 via the connecting rod 22. The self-locking assembly is used to lock and unlock the valve body 21.

[0049] Specifically, during implementation, after the machine tool hydraulic station is started, the pressurized oil is delivered to the inner oil cylinder 13 through the oil circuit assembly. The pressurized oil pushes the piston block 14 to move, and the piston block 14 pushes the chuck 12 to move through the first connecting column 15 to clamp the workpiece.

[0050] like Figure 7 and Figure 9 As shown, during the clamping process, the first connecting post 15 drives the second connecting post 19 to move synchronously through the collar 20. The second connecting post 19 drives the piston ring 17 to move in the annular cavity. When the piston ring 17 moves, it will squeeze the hydraulic oil in one side chamber and squeeze the hydraulic oil in that side chamber into the other side chamber through the connecting pipe 18, thereby ensuring that the two side chambers are always filled with hydraulic oil. When the clamping action is completed, the self-locking component pulls the valve stem on the valve body 21 through the connecting rod 22. The valve body 21 is specifically an axial direct-acting gate valve. The gate moves axially linearly with the valve stem. The gate can cut into or out of the fluid passage, thereby realizing the shut-off and opening of the two connecting pipes 18.

[0051] When the gate moves and closes the two connecting pipes 18, the hydraulic oil in the chambers on both sides of the piston ring 17 cannot flow. Since the hydraulic medium is incompressible, the piston ring 17 is locked by the hydraulic medium on both sides and cannot move, thus achieving self-locking of the piston ring 17.

[0052] In extreme operating conditions, such as when the oil circuit assembly ruptures, the piston block 14 loses the force of the pressurized oil and tends to move backward and loosen. However, since the piston ring 17 is self-locking and cannot move, the first connecting post 15 can be locked by the second connecting post 19 and the collar 20, limiting the displacement of the first connecting post 15. This prevents the first connecting post 15 from moving backward with the piston block 14, ensuring the clamping effect of the chuck 12 on the workpiece. This can eliminate the safety hazard of the workpiece loosening and flying out under high-speed rotation.

[0053] After the workpiece is clamped by the rotary chuck assembly, the tailstock sleeve 2 is fed axially along the main shaft 4, so that the tailstock sleeve 2 presses against the tail end of the workpiece. Thus, the workpiece is in a double-supported positioning state where one end is clamped by the rotary chuck assembly and the other end is pressed against the tailstock sleeve 2. A servo motor is also installed in the frame 1. The output shaft of the servo motor and the main shaft 4 are equipped with meshing gears. When the servo motor is running, the main shaft 4 can be driven to rotate at high speed through gear transmission. The main shaft 4 drives the rotary chuck assembly to rotate at high speed, and the chuck 12 drives the workpiece to rotate synchronously.

[0054] After the corresponding tool is installed on the tool holder 3, the linear screw mechanism drives the tool holder 3 to perform transverse or radial feed motion according to the command. The rotating workpiece and the feed tool generate relative cutting motion, and the tool performs turning machining on the outer circle, end face, conical surface or thread of the workpiece.

[0055] The connecting rod 22 is connected to the valve stem via a flange. A return spring is fitted on the valve stem, and both ends of the return spring are welded to the flange and the outer wall of the valve body 21. When the valve stem is pulled by the connecting rod 22, the return spring is stretched. After the workpiece is processed, the self-locking assembly releases its self-locking state. At this time, under the elastic force of the return spring, the valve stem is pulled upward to reset, and the gate plate moves upward axially to reset. The gate plate completely exits the flow channel of the connecting pipe 18, and the valve body 21 returns to the fully open state. The two chambers of the piston ring 17 are reconnected through the connecting pipe 18, and the piston ring 17 regains its ability to move freely axially. Subsequently, the hydraulic station depressurizes, and the built-in spring inside the inner oil cylinder 13 can push the piston block 14 to reset. At this time, the piston ring 17 can move synchronously with the piston block 14. In this way, the piston block 14 drives the chuck 12 to separate from the workpiece through the first connecting column 15, and the workpiece can be taken out from the rotary chuck assembly.

[0056] In one specific embodiment of the present invention, an oil circuit assembly for conveying oil to the inner oil cylinder 13 is also included. The oil circuit assembly includes a hydraulic oil pipe 5, a rotary oil cylinder 6, and an internal oil pipe 7.

[0057] The frame 1 is connected to the rotary cylinder 6 by a bearing. One end of the rotary cylinder 6 is connected to the hydraulic oil pipe 5 through a sealed rotary joint. The other end of the rotary cylinder 6 is welded to the built-in oil pipe 7. The rotary cylinder 6 is fixedly connected to one end of the main shaft 4 through a flange.

[0058] The built-in oil pipe 7 is located inside the spindle 4, and one end of the built-in oil pipe 7 is welded and fixed to the rotary cylinder 6 and connected to it.

[0059] Specifically, such as Figure 1 , Figure 2 and Figure 3 As shown, after the hydraulic station is started, the hydraulic oil is transported to the hydraulic oil pipe 5, and then transported to the built-in oil pipe 7 through the rotary cylinder 6. Finally, it is distributed to multiple inner oil cylinders 13 through other components. Through the combination of multiple components, a complete and sealed oil flow channel can be formed to ensure stable clamping of the workpiece.

[0060] In one specific embodiment of the present invention, the rotary chuck assembly further includes a hollow oil guide ring 8 and an annular connecting seat 10. One end of the built-in oil pipe 7 is closed and passes through the connecting seat 10. The closed end of the built-in oil pipe 7 is connected to the oil guide ring 8 through multiple oil guide pipes 9. The top end of the inner oil cylinder 13 is open. The top end of the inner oil cylinder 13 is welded and fixed to the inner circular wall of the oil guide ring 8 and connected to it.

[0061] The connecting seat 10 is fixedly connected to the flange at one end of the spindle 4. The outer circular wall of the connecting seat 10 and the chuck 11 and the inner circular wall of the oil guide ring 8 are welded together. The oil guide pipe 9 is located between the connecting seat 10 and the chuck 11.

[0062] Specifically, such as Figure 3 , Figure 4 and Figure 5 As shown, when the oil flows from the open end of the built-in oil pipe 7 to the closed port, it will enter the oil guide ring 8 through multiple oil guide pipes 9, and finally be distributed into multiple inner oil cylinders 13. The oil guide pipe 9 is completely wrapped by the connecting seat 10 and the chuck 11, thus avoiding damage caused by collision with external objects.

[0063] Furthermore, the connecting seat 10, chuck 11, and oil guide ring 8 form a whole, so that the main shaft 4 can drive the three to rotate synchronously. In this way, the pressure loss protection component and the self-locking component can rotate synchronously with the inner oil cylinder 13, ensuring that pressure loss protection and self-locking can be achieved during rotation.

[0064] The inner oil cylinder 13 is welded to the outer cylinder 16, which ensures that the chambers on both sides of the piston ring 17 are sealed and prevents oil leakage inside the chambers. A rubber sleeve can be fitted on the entire outer cylinder 16. One end of the rubber strip is sealed and bonded to the outer circular wall of the collar 20, and the other end is sealed and bonded to the inner circle of the oil guide ring 8. This can prevent waste from adhering to the second connecting post 19 and the first connecting post 15, avoiding parts jamming and wear, and affecting the reliability of the mechanism.

[0065] In one specific embodiment of the present invention, a rotating ring 35 is connected to the frame 1 bearing on one side of the connecting seat 10. The rotating ring 35 is provided with a plurality of notches, and a movable strip 36 is inserted into the notches. An electromagnet 37 is provided on the movable strip 36, and the electromagnet 37 is coaxial with the fixed cylinder 24.

[0066] Specifically, such as Figure 4 and Figure 11 As shown, the rotating ring 35 is arranged parallel to the connecting seat 10, and the two are not in contact. Therefore, the rotation of the connecting seat 10 will not affect the rotating ring 35. Thus, the electromagnet 37 does not need to be equipped with components such as conductive slip rings, thereby reducing the complexity of the equipment.

[0067] When electromagnet 37 is damaged, there is no need to remove the connector 10 and chuck 11. Electromagnet 37 can be replaced by inserting and removing the movable bar 36. The rotating ring 35 can rotate axially as a whole. By rotating, multiple movable bars 36 can be pulled out one by one, so that any electromagnet 37 can be maintained. The operation is convenient.

[0068] In one specific embodiment of the present invention, the self-locking assembly includes a fixed cylinder 24 and a movable block 23 located inside the fixed cylinder 24. The fixed cylinder 24 has a connecting seat 10 and a chuck 11 passing through both ends. One end of the movable block 23 is fixedly connected to the connecting rod 22, and the other end of the movable block 23 has a groove 25. A movable piece 26 is provided inside the groove 25. A magnet piece 27 is embedded on the outer side of the movable piece 26. A guide post 28 is welded and fixed at the center of the inner side of the movable piece 26. A guide groove for the insertion of the guide post 28 is provided at the bottom of the groove 25. A first spring 29 is sleeved on the guide post 28. Both ends of the first spring 29 are welded and connected to the guide post 28 and the bottom of the groove 25.

[0069] Specifically, such as Figure 7 and Figure 8 As shown, both ends of the fixed cylinder 24 are welded to the connecting seat 10 and the chuck 11, so that the fixed cylinder 24 will not fall off when the connecting seat 10 rotates at high speed.

[0070] After the workpiece is clamped by the chuck 12, since the electromagnet 37 is aligned with the fixed cylinder 24, when the electromagnet 37 is energized, the electromagnet 37 and the magnet 27 generate an axial magnetic attraction force, which in turn pulls the movable plate 26 to move through the magnet 27. The movable plate 26 moves synchronously while pulling the movable block 23, and the movable block 23 can pull the valve stem axially through the connecting rod 22.

[0071] In one specific embodiment of the present invention, the inner diameter of the fixed cylinder 24 is the same as the outer diameter of the movable block 23. A set of symmetrically distributed holes and grooves 32 are provided on the inner wall of the fixed cylinder 24, and a set of symmetrically distributed pin holes 30 are provided on the outer wall of the movable block 23. The bottom end of the pin hole 30 is connected to the groove 25.

[0072] A movable pin 33 is inserted into the slot 32, and the top of the movable pin 33 is connected to the bottom of the slot 32 by a second spring 34.

[0073] The axes of the slot 32 and the pin hole 30 are both inclined, the inclination angles of the slot 32 and the pin hole 30 are the same, and the inner diameters of the slot 32 and the pin hole 30 are the same.

[0074] A set of symmetrically distributed magnet posts 31 are welded and fixed on the inner side of the movable piece 26. The top of the magnet post 31 is a slope, and a magnetic block is embedded at the bottom of the movable pin 33. The top of the magnet post 31 and the surface of the magnetic block are magnetic poles of the same name.

[0075] Specifically, such as Figure 7 , Figure 8 and Figure 10 As shown, the inner wall of the fixed cylinder 24 and the outer wall of the movable block 23 are in contact, and the slot 32 and the pin hole 30 are staggered. The movable pin 33 is radially pressed by the cylindrical outer wall of the movable block 23 and compressed into the slot 32. The rounded chamfer at the end of the movable pin 33 is in contact with the outer wall of the movable block 23, and the self-locking mechanism is in the unlocked state.

[0076] As the movable block 23 moves axially, the slot 32 aligns with the pin hole 30. At this time, the movable pin 33 is inserted into the pin hole 30 under the push of the second spring 34, thus completing the locking of the valve stem. After locking is completed, the electromagnet 37 is de-energized.

[0077] When unlocking is required, the electromagnet 37 is reverse-energized, and the electromagnet 37, together with the magnet 27, generates an axial magnetic repulsion force. At this time, the movable block 23 is restricted by the movable pin 33 and cannot move. The magnetic repulsion force only pushes the movable piece 26 to move within the groove 25. The movable piece 26 moves axially along the guide groove through the guide post 28 and compresses the first spring 29. During this process, the magnet post 31 moves synchronously with the movable piece 26. When the top of the magnet post 31 is opposite to the bottom of the movable pin 33, an oblique magnetic repulsion force is generated. The magnetic repulsion force pushes the movable pin 33 to move in the opposite direction along its axis. In this way, the movable pin 33 can complete the exit of the pin hole 30. The movable block 23 is unrestricted and resets under the pull of the reset spring. The movable block 23 can push the valve stem to move axially and reset through the connecting rod 22.

[0078] Once unlocking is complete, the electromagnet 37 is de-energized, the movable piece 26 loses its magnetic repulsion, and can be reset under the push of the first spring 29.

[0079] In the description of this specification, terms such as "connection," "installation," and "fixation" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meanings of the above terms within this invention based on the specific circumstances.

[0080] In the description of this specification, the terms "one embodiment," "some embodiments," "specific embodiment," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0081] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A CNC machine tool with locking protection, comprising a frame (1) and a rotary chuck assembly located within the frame (1), Its features are: It also includes a pressure loss protection component and a self-locking component that rotate synchronously with the rotary chuck assembly, and a spindle (4) for driving the rotary chuck assembly to rotate. The rotary chuck includes multiple inner oil cylinders (13) arranged in a ring. A piston block (14) is provided inside the inner oil cylinder (13). A first connecting post (15) is welded and fixed to one end of the piston block (14). The other end of the first connecting post (15) passes through the inner oil cylinder (13) and is welded and fixed to a chuck (12). The pressure loss protection assembly includes an outer cylinder (16) sleeved on the inner oil cylinder (13). The inner wall of the outer cylinder (16) and the outer wall of the inner oil cylinder (13) enclose a sealed annular cavity. A piston ring (17) that moves synchronously with the piston block (14) is provided in the annular cavity. The piston ring (17) divides the annular cavity into two chambers filled with hydraulic oil. The outer cylinder (16) walls at both chambers are welded with connecting pipes (18). The two connecting pipes (18) are sealed to the flange of the valve body (21). The self-locking assembly is connected to the valve stem on the valve body (21) via a connecting rod. The self-locking assembly is used to lock and unlock the valve body (21).

2. A CNC machine tool with locking protection according to claim 1, characterized in that: The frame (1) is also provided with a tailstock sleeve (2) that cooperates with the rotary chuck assembly, and a tool holder (3) for placing the tool is provided between the rotary chuck assembly and the tailstock sleeve (2).

3. A CNC machine tool with locking protection according to claim 1, characterized in that: It also includes an oil circuit assembly for conveying oil to the inner oil cylinder (13), the oil circuit assembly including a hydraulic oil pipe (5), a rotary cylinder (6) and an internal oil pipe (7). The frame (1) is connected to the rotary cylinder (6) by bearings. One end of the rotary cylinder (6) is connected to the hydraulic oil pipe (5) through a sealed rotary joint. The other end of the rotary cylinder (6) is welded to the built-in oil pipe (7). The rotary cylinder (6) is fixedly connected to one end of the main shaft (4) through a flange. The built-in oil pipe (7) is located inside the main shaft (4), and one end of the built-in oil pipe (7) is welded and fixed to the rotary cylinder (6) and connected.

4. A CNC machine tool with locking protection according to claim 3, characterized in that: The rotary chuck assembly also includes a hollow oil guide ring (8) and an annular connecting seat (10). One end of the built-in oil pipe (7) is closed and passes through the connecting seat (10). The closed end of the built-in oil pipe (7) is connected to the oil guide ring (8) through multiple oil guide pipes (9). The top end of the inner oil cylinder (13) is open. The top end of the inner oil cylinder (13) is welded and fixed to the inner circular wall of the oil guide ring (8) and connected to it. The connecting seat (10) is fixedly connected to the flange at one end of the main shaft (4). The outer circular wall of the connecting seat (10) and the inner circular wall of the oil guide ring (8) are welded together. The oil guide pipe (9) is located between the connecting seat (10) and the chuck (11).

5. A CNC machine tool with locking protection according to claim 1, characterized in that: A set of second connecting posts (19) are welded and fixed on the piston ring (17). One end of the second connecting post (19) passes through the outer cylinder (16) and is welded and fixed to the collar (20). The collar (20) is sleeved and fixed on the first connecting post (15).

6. A CNC machine tool with locking protection according to claim 1, characterized in that: The self-locking assembly includes a fixed cylinder (24) and a movable block (23) located inside the fixed cylinder (24). The fixed cylinder (24) has a connecting seat (10) and a chuck (11) passing through both ends. One end of the movable block (23) is fixedly connected to the connecting rod (22). The other end of the movable block (23) has a groove (25). A movable piece (26) is provided inside the groove (25). A magnet piece (27) is embedded on the outer side of the movable piece (26). A guide post (28) is welded and fixed at the center of the inner side of the movable piece (26). A guide groove for the insertion of the guide post (28) is provided at the bottom of the groove (25). A first spring (29) is sleeved on the guide post (28). Both ends of the first spring (29) are welded and connected to the guide post (28) and the bottom of the groove (25).

7. A CNC machine tool with locking protection according to claim 6, characterized in that: The inner diameter of the fixed cylinder (24) is the same as the outer diameter of the movable block (23). A set of symmetrically distributed slots (32) are provided on the inner wall of the fixed cylinder (24), and a set of symmetrically distributed pin holes (30) are provided on the outer wall of the movable block (23). The bottom end of the pin hole (30) is connected to the groove (25). A movable pin (33) is inserted into the slot (32), and the top of the movable pin (33) is connected to the bottom of the slot (32) by a second spring (34).

8. A CNC machine tool with locking protection according to claim 7, characterized in that: The axes of the slot (32) and the pin hole (30) are both inclined, the inclination angles of the slot (32) and the pin hole (30) are the same, and the inner diameters of the slot (32) and the pin hole (30) are the same.

9. A CNC machine tool with locking protection according to claim 6, characterized in that: A set of symmetrically distributed magnet columns (31) are welded and fixed on the inner side of the movable piece (26). The top of the magnet column (31) is a slope, and a magnetic block is embedded at the bottom of the movable pin (33). The top of the magnet column (31) and the surface of the magnetic block are magnetic poles of the same name.

10. A CNC machine tool with locking protection according to claim 1, characterized in that: A rotating ring (35) is connected to the frame (1) on one side of the connecting seat (10). The rotating ring (35) has multiple notches, and a movable strip (36) is inserted into the notch. An electromagnet (37) is provided on the movable strip (36). The electromagnet (37) and the fixed cylinder (24) are coaxial.

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