A multi-axis rotary polishing machine tool for turbine blade machining

Abstract

This invention relates to the field of blade processing equipment technology, and more particularly to a multi-axis rotary polishing machine tool for processing steam turbine blades, comprising: a frame, a grinding wheel base, a mounting shaft, and a clamping seat; the mounting shaft is rotatably connected to the frame; the clamping seat is rotatably connected to the mounting shaft; the grinding wheel base is connected to the frame; the support mechanism can clamp the blade and perform polishing on the blade's fluttering parts, thereby increasing the stiffness of the blade at the clamped part, and thus increasing the blade's natural frequency and eliminating flutter; this invention improves the stiffness of the polished part of the blade edge by clamping the clamping shaft on both sides of the thinner part of the blade edge during polishing, thereby increasing the natural frequency of that part of the blade, so that the natural frequency of the blade at the polished part is offset from the high-frequency vibration frequency generated by the rapid rotation of the grinding wheel base during polishing, thereby reducing the occurrence of flutter during polishing.

Description

Technical Field

[0001] This invention relates to the field of blade processing equipment technology, and in particular to a multi-axis rotary polishing machine tool for processing steam turbine blades. Background Technology

[0002] Steam turbines are core equipment in the fields of power generation and drive. The core component inside the steam turbine, the blades, must withstand extreme tests of high temperature, high pressure and high speed rotation during operation. Therefore, the manufacturing quality of the blades, especially their surface smoothness, directly determines the efficiency and lifespan of the entire unit.

[0003] In the existing technology, a multi-axis rotary polishing machine tool is used to polish turbine blades. The blades are clamped on the fixture of the polishing machine tool, the polishing abrasive of the machine tool contacts the blades and polishes them, and at the same time the fixture drives the blades to rotate to adjust the blade angle so that the blades fit into the polishing mold.

[0004] During the polishing process of the blade, the polishing abrasive rubs against the blade, causing the blade to vibrate. When the frequency of the vibration is the same as the frequency of the blade, it will aggravate the vibration of the blade, thus producing flutter. The polishing abrasive forms vibration marks on the surface of the blade, affecting the quality of the blade and causing limitations.

[0005] Therefore, we propose a multi-axis rotary polishing machine tool for machining steam turbine blades. Summary of the Invention

[0006] In view of the shortcomings of the prior art, the present invention provides a multi-axis rotary polishing machine tool for processing steam turbine blades, which overcomes the shortcomings of the prior art and aims to solve the problems in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a multi-axis rotary polishing machine tool for machining turbine blades, comprising:

[0008] The machine includes a frame, a mold holder, a mounting shaft, and a clamping seat; the mounting shaft is rotatably connected to the frame; the clamping seat is rotatably connected to the mounting shaft; the mold holder is connected to the frame; a motor for driving the mounting shaft to rotate is mounted on the frame; a motor for driving the clamping seat to rotate is mounted on the mounting shaft.

[0009] The frame is equipped with a support mechanism; the support mechanism can clamp the blade, clamp and support the thinner parts of the blade, and improve the rigidity of the blade at the clamped part.

[0010] Preferably, the support mechanism includes a mounting ring, a support rod, a lifting block, and a clamping shaft; the mounting ring is mounted on the frame and located above the clamping seat; the mounting ring is provided with a toothed ring; the support rod is slidably connected to the mounting ring; the lifting block is slidably connected to the support rod; a rotating shaft is rotatably connected to the lifting block; the rotating shaft is fixedly connected to the rotating block; the clamping shaft is mounted on the rotating block; a rubber layer is rotatably connected to the clamping shaft; a rotating electric push rod is connected between the lifting block and the rotating block; a separate lead screw is provided inside the support rod and connected to the lifting block; a motor is provided above the support rod to drive the lead screw to rotate.

[0011] A rotating motor is installed inside the support rod; the output end of the rotating motor is fixedly connected to a gear that meshes with the gear ring.

[0012] Preferably, the clamping shaft is spherically hinged to the rotating block, and a return spring is connected between the clamping shaft and the rotating block.

[0013] Preferably, a connecting block is slidably connected to the support rod; a winding block is symmetrically slidably connected to the connecting block; a lead screw with opposite threads at both ends is provided on the connecting block, and a motor connected to the lead screw is provided on the connecting block; a winding shaft is rotatably connected to the winding block; a winding belt is wound on the winding shaft; electromagnet blocks are uniformly fixedly connected to the winding belt; the winding belt can provide counterweight for the blade; a motor is provided on the winding block to drive the winding shaft to rotate; a separate lead screw is provided inside the support rod and connected to the connecting block; a motor is provided above the support rod to drive the corresponding lead screw to rotate.

[0014] Preferably, the take-up tape is in the shape of a flexible water pipe, both ends of the take-up tape are closed, and the lower end of the take-up tape is connected to a connecting pipe.

[0015] Preferably, a first block is fixedly connected to the connecting block, a second block is slidably connected to the connecting block, and a clamping electric push rod is fixedly connected to the connecting block; the output end of the clamping electric push rod is fixedly connected to the second block.

[0016] Preferably, a detection rod is slidably connected to the mounting ring; a detection block is slidably connected to the detection rod; a detection electric push rod is connected between the detection block and the detection rod; a striking rod and a contact rod are slidably connected to the detection block; a pressure sensor and a striking electromagnet are provided inside the detection block; a spring is connected between the striking rod and the detection block; and a spring is connected between the contact rod and the pressure sensor.

[0017] The beneficial effects of this invention are:

[0018] 1. The present invention improves the rigidity of the polished part of the blade edge by clamping the clamping shaft on the front and rear sides of the thinner part of the blade edge during polishing, thereby increasing the natural frequency of that part of the blade. This makes the natural frequency of the blade at the polished part different from the high-frequency vibration frequency generated by the rapid rotation of the grinding wheel during polishing, thereby reducing the occurrence of chatter during polishing.

[0019] 2. This invention uses a winding block and winding belt on a support rod, with the blade positioned between the two winding belts. The winding belts clamp the blade's sides under the action of an electromagnet block. Water is then poured into the winding belts to increase the weight of the blade and reduce its natural frequency. This invention employs two methods: increasing the blade frequency and decreasing the blade frequency. However, if the blade's natural frequency is close to the low-frequency vibrations generated by other equipment in the surrounding polishing environment, increasing the blade's frequency can easily lead to the blade's frequency becoming close to the vibrations generated by the polishing tool during fine polishing. Therefore, using only one method to change the blade's frequency to avoid vibration can easily result in the blade's frequency becoming close to the vibration frequency generated by another vibration source, thus limiting its effectiveness. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of the mounting shaft, clamping seat, mounting ring, support rod and lifting block in this invention;

[0022] Figure 3 for Figure 2 Enlarged view of point A in the middle;

[0023] Figure 4 for Figure 2 Enlarged view of point B in the middle;

[0024] Figure 5 for Figure 4 Enlarged view of point C in the middle;

[0025] Figure 6 This is a cross-sectional view of the detection rod and detection block in this invention;

[0026] Figure 7 This is a schematic diagram of the lifting block, rotating block, and rotating electric push rod in this invention.

[0027] In the diagram: 1. Frame; 11. Mold holder; 12. Mounting shaft; 13. Clamping seat; 21. Mounting ring; 22. Support rod; 23. Lifting block; 24. Clamping shaft; 25. Gear ring; 26. Rotating block; 27. Rubber layer; 28. Return spring; 3. Connecting block; 31. Rewinding shaft; 32. Rewinding belt; 33. Electromagnetic block; 34. Connecting pipe; 35. Block 1; 36. Block 2; 37. Clamping electric push rod; 4. Detection rod; 41. Detection block; 42. Detection electric push rod; 43. Striking rod; 44. Contact rod; 45. Pressure sensor; 46. Striking electromagnet; 5. Rotating electric push rod; 6. Rewinding block; 7. Rotating shaft. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] Example 1: Refer to the appendix of the instruction manual. Figure 1 , 2 3 and 7, a multi-axis rotary polishing machine tool for machining steam turbine blades, comprising:

[0030] The machine frame 1, the mold base 11, the mounting shaft 12, and the clamping seat 13 are rotatably connected to the machine frame 1; the clamping seat 13 is rotatably connected to the mounting shaft 12; the mold base 11 is connected to the machine frame 1; a motor for driving the mounting shaft 12 to rotate is provided on the machine frame 1; a motor for driving the clamping seat 13 to rotate is provided on the mounting shaft 12.

[0031] A support mechanism is installed on the frame 1; the support mechanism can clamp the blade, clamp and support the thinner parts of the blade, and improve the rigidity of the blade in the clamped part.

[0032] In this invention, the support mechanism includes a mounting ring 21, a support rod 22, a lifting block 23, and a clamping shaft 24. The mounting ring 21 is mounted on the frame 1 and located above the clamping seat 13. A toothed ring 25 is provided on the mounting ring 21. The support rod 22 is slidably connected to the mounting ring 21. The lifting block 23 is slidably connected to the support rod 22. A rotating shaft 7 is rotatably connected to the lifting block 23. The rotating shaft 7 is fixedly connected to the rotating block 26. The clamping shaft 24 is mounted on the rotating block 26. A rubber layer 27 is rotatably connected to the clamping shaft 24. A rotating electric push rod 5 is connected between the lifting block 23 and the rotating block 26. A separate lead screw is provided inside the support rod 22 and connected to the lifting block 23. A motor is provided above the support rod 22 to drive the lead screw to rotate.

[0033] A rotating motor is installed inside the support rod 22; the output end of the rotating motor is fixedly connected to a gear that meshes with the gear ring 25.

[0034] In this invention, the clamping shaft 24 is spherically hinged to the rotating block 26, and a return spring 28 is connected between the clamping shaft 24 and the rotating block 26.

[0035] In this invention, the turbine blade is clamped on the clamping seat 13, with the blade positioned between the two clamping shafts 24 on the rotating block 26. Then, the electric push rod 5 is rotated to drive the rotating block 26 to rotate, causing the two clamping shafts 24 on the rotating block 26 to contact the front and rear surfaces of the turbine blade, thus clamping the turbine blade. Next, the grinding wheel seat 11 moves towards the direction close to the turbine blade and sprays polishing fluid, polishing the turbine blade. The mounting shaft 12 and the clamping seat 13 rotate, causing the turbine blade to deflect and adjust its angle, so that the turbine blade is aligned with the front and rear surfaces of the turbine blade. The grinding contact surface on the grinding mold base 11 reaches its maximum. During the grinding and polishing process, the clamping shaft 24 is clamped on the front and rear sides of the turbine blade. The motor on the support rod 22 drives the corresponding lead screw to rotate, so that the lifting block 23 moves up and down with the rotating block 26 and the clamping shaft 24. Thus, the clamping shaft 24 can move synchronously with the grinding and polishing of the grinding mold base 11, and clamp the part of the turbine blade being ground and polished in real time. This improves the rigidity of the thinner edge of the turbine blade when it is ground and polished, thereby increasing the natural frequency of the blade and reducing the occurrence of flutter.

[0036] The motor inside the support rod 22 drives the gear to rotate, causing the support rod 22, along with the lifting block 23, the rotating block 26 and the clamping shaft 24, to rotate along the mounting ring 21, so that the entire support mechanism can rotate together with the clamping seat 13;

[0037] In this invention, the clamping shaft 24 is spherically hinged to the rotating block 26, so that the clamping shaft 24 can rotate in any direction, thereby better fitting with the blade, and the return spring 28 can provide clamping pressure.

[0038] The present invention improves the rigidity of the polished part of the blade edge by clamping the clamping shaft 24 on the front and rear sides of the thinner part of the blade edge during polishing, thereby increasing the natural frequency of that part of the blade. This makes the natural frequency of the blade in the polished part different from the high frequency of vibration generated by the rapid rotation of the grinding wheel 11 during polishing, thereby reducing the occurrence of chatter during polishing.

[0039] Example 2: Based on Example 1, refer to the appendix of the instruction manual. Figure 1 , 2In the present invention, 4 and 5, a connecting block 3 is slidably connected to the support rod 22; a winding block 6 is symmetrically slidably connected to the connecting block 3; a lead screw with opposite threads at both ends is provided on the connecting block 3, and a motor connected to the lead screw is provided on the connecting block 3; a winding shaft 31 is rotatably connected to the winding block 6; a winding belt 32 is wound on the winding shaft 31; an electromagnet block 33 is uniformly fixedly connected to the winding belt 32; the winding belt 32 can provide counterweight for the blade; a motor is provided on the winding block 6 to drive the winding shaft 31 to rotate; a separate lead screw is provided inside the support rod 22 and connected to the connecting block; a motor is provided above the support rod to drive the corresponding lead screw to rotate.

[0040] In this invention, the take-up tape 32 is a flexible water tube, with both ends of the take-up tape 32 closed, and the lower end of the take-up tape 32 is connected to a connecting pipe 34.

[0041] In this invention, a first block 35 is fixedly connected to the connecting block 3, a second block 36 is slidably connected to the connecting block 3, and a clamping electric push rod 37 is fixedly connected to the connecting block 3; the output end of the clamping electric push rod 37 is fixedly connected to the second block 36.

[0042] In this invention, the connecting pipe 34 is connected to a water source. A connecting block 3 and a take-up belt 32 are installed on the support rod 22. When low-frequency vibrations occur in other equipment around the polishing site, the motor on the connecting block 3 drives the corresponding lead screw to rotate. Under the action of the oppositely oriented threads at both ends, the two take-up blocks 6 approach each other. The motor on the take-up block 6 drives the take-up shaft 31 to rotate, causing the take-up belt 32 to be released. Furthermore, the take-up belts 32 on both sides of the blade are attracted to each other by the electromagnet block 33. Under the generated magnetic force, the take-up belt 32 adheres to the blade. On the blade, water is then introduced into the take-up tape 32 through the connecting pipe 34. The clamping electric push rod 37 drives the second block 36 to move, so that the second block 36 and the first block 35 clamp and seal the water-filled part of the take-up tape 32, thereby increasing the weight of the blade. The increased weight of the blade can reduce the blade's own frequency, thereby avoiding the low-frequency vibration of the surrounding environment or the low-frequency vibration generated by the abrasive of the abrasive in the abrasive seat 11 during the rough grinding and polishing of the blade, thus providing a variety of ways to adjust the blade's own frequency.

[0043] This invention uses a winding block 6 and a winding belt 32 on a support rod 22. The blade is located between the two winding belts 32. The winding belts 32 clamp the two sides of the blade under the action of an electromagnet block 33. Water is then poured into the winding belts 32 to increase the weight of the blade and reduce its natural frequency. This invention employs two methods: increasing the blade frequency and decreasing the blade frequency. However, if the natural frequency of the blade is close to the low-frequency vibration generated by other equipment in the surrounding polishing environment, increasing the blade frequency may cause the blade frequency to approach the vibration generated by the polishing tool during fine polishing. Therefore, using only one method to change the blade frequency to avoid vibration may result in the blade frequency approaching the vibration frequency generated by another vibration source, thus limiting its effectiveness.

[0044] Example 3: Based on Example 2, refer to the appendix of the instruction manual. Figure 1 , 2 In the present invention, a detection rod 4 is slidably connected to the mounting ring 21; a detection block 41 is slidably connected to the detection rod 4; a detection electric push rod 42 is connected between the detection block 41 and the detection rod 4; a striking rod 43 and a contact rod 44 are slidably connected to the detection block 41; a pressure sensor 45 and a striking electromagnet 46 are provided inside the detection block 41; a spring is connected between the striking rod 43 and the detection block 41; and a spring is connected between the contact rod 44 and the pressure sensor 45.

[0045] In this invention, after the blade is clamped on the clamping seat 13, the detection electric push rod 42 pushes the detection block 41 to extend the detection rod 4, so that the contact rod 44 and the striking rod 43 come into contact with the turbine blade. Then, the striking electromagnet 46 attracts the striking rod 43, so that the spring between the striking rod 43 and the detection block 41 is compressed. Then, the striking electromagnet 46 stops attracting. Under the action of the striking electromagnet 46, the striking rod 43 strikes the turbine blade. The contact rod 44 transmits the vibration generated by the blade after being struck to the pressure sensor 45 through the spring. The vibration frequency of the blade after being struck is detected according to the force on the pressure sensor 45, thereby detecting the blade's own natural frequency. Then, according to the blade's own frequency, the blade is processed to increase or decrease the frequency.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-axis rotary polishing machine tool for turbine blade machining, characterized by: include: A frame (1), a mold holder (11), a mounting shaft (12), and a clamping seat (13); the mounting shaft (12) is rotatably connected to the frame (1); the clamping seat (13) is rotatably connected to the mounting shaft (12); the mold holder (11) is connected to the frame (1); a motor for driving the mounting shaft (12) to rotate is provided on the frame (1); a motor for driving the clamping seat (13) to rotate is provided on the mounting shaft (12); A support mechanism is installed on the frame (1); the support mechanism can clamp the blade, clamp and support the thinner part of the blade, and improve the rigidity of the blade in the clamped part. The support mechanism includes an mounting ring (21), a support rod (22), a lifting block (23), and a clamping shaft (24); the mounting ring (21) is mounted on the frame (1) and located above the clamping seat (13); a toothed ring (25) is provided on the mounting ring (21); the support rod (22) is slidably connected to the mounting ring (21); the lifting block (23) is slidably connected to the support rod (22); a rotating shaft (7) is rotatably connected to the lifting block (23); the rotating shaft (7) is fixedly connected to the rotating block (26); the clamping shaft (24) is mounted on the rotating block (26); a rubber layer (27) is rotatably connected to the clamping shaft (24); a rotating electric push rod (5) is connected between the lifting block (23) and the rotating block (26); a rotating motor is provided inside the support rod (22); a gear that meshes with the toothed ring (25) is fixedly connected to the output end of the rotating motor; The clamping shaft (24) is spherically hinged to the rotating block (26), and a return spring (28) is connected between the clamping shaft (24) and the rotating block (26). A connecting block (3) is slidably connected to the support rod (22); a winding block (6) is symmetrically slidably connected to the connecting block (3); a lead screw with opposite threads at both ends is provided on the connecting block (3), and a motor connected to the lead screw is provided on the connecting block (3); a winding shaft (31) is rotatably connected to the winding block (6); a winding belt (32) is wound on the winding shaft (31); an electromagnet block (33) is uniformly fixedly connected to the winding belt (32); the winding belt (32) can counterweight the blade; a motor is provided on the winding block (6) to drive the winding shaft (31) to rotate.

2. The multi-axis rotary polishing machine tool for machining turbine blades according to claim 1, characterized in that: The take-up tape (32) is a flexible water tube, with both ends of the take-up tape (32) closed, and the lower end of the take-up tape (32) is connected to a connecting pipe (34).

3. The multi-axis rotary polishing machine tool for processing steam turbine blades according to claim 2, characterized in that: A first block (35) is fixedly connected to the connecting block (3), a second block (36) is slidably connected to the connecting block (3), and a clamping electric push rod (37) is fixedly connected to the connecting block (3); the output end of the clamping electric push rod (37) is fixedly connected to the second block (36).

4. The multi-axis rotary polishing machine tool for machining turbine blades according to claim 3, characterized in that: A detection rod (4) is slidably connected to the mounting ring (21); a detection block (41) is slidably connected to the detection rod (4); a detection electric push rod (42) is connected between the detection block (41) and the detection rod (4); a striking rod (43) and a contact rod (44) are slidably connected to the detection block (41); a pressure sensor (45) and a striking electromagnet (46) are provided inside the detection block (41); a spring is connected between the striking rod (43) and the detection block (41); a spring is connected between the contact rod (44) and the pressure sensor (45).

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