Electromagnetic impact device for casting sprues

Abstract

The application belongs to the technical field of gating and riser cleaning equipment of castings, and particularly relates to a castings gating and riser electromagnetic impact device, which comprises an impact head, a shell, a shaft, an electromagnetic loading module, a first buffer assembly and a second buffer assembly. The one end of the shaft is inserted into the shell, and the other end is connected with the impact head. The electromagnetic loading module comprises a primary coil and a secondary coil. The primary coil is sleeved on the shaft through a coil base, and the secondary coil is fixed with the shaft through a coil support. The first buffer assembly comprises a first mass block, a first buffer spring and a pressing part. The shaft passes through a through hole on the first mass block. The pressing part is connected with the shaft. The first buffer spring is arranged in the through hole and sleeved on the shaft. The pressing part abuts against one end of the first buffer spring. The second buffer assembly is arranged between the coil base and the side wall of the shell and is used for buffering the primary coil under the repulsion effect. The device effectively improves the buffering effect of the electromagnetic loading module and expands the application range of the device.

Description

Technical Field

[0001] This invention belongs to the technical field of casting gating and riser cleaning equipment, specifically relating to an electromagnetic impact device for casting gating and riser. Background Technology

[0002] In recent years, with the rapid development of my country's foundry industry, the demand for large castings has increased year by year, making riser and gating system cleaning equipment technology increasingly important. This technology plays a crucial role in improving production efficiency and ensuring casting quality.

[0003] Traditional cleaning methods include manual hammering, gas cutting, and flame cutting. However, these methods are not only inefficient and labor-intensive, but also costly and difficult to train operators, posing safety risks, being susceptible to human error, and exhibiting high instability. Although pneumatic hammers, as a mechanized cleaning device, have been applied to the cleaning of risers and gating gates of large castings, their air storage and hammer body series structure still has a series of problems. While pneumatic hammers are simpler to operate and have better safety performance compared to traditional cleaning methods, they still suffer from drawbacks such as high vibration, high noise, and large size. From an energy and energy consumption perspective, they utilize secondary energy, resulting in low energy utilization and high energy consumption. Furthermore, both traditional cleaning methods and the use of pneumatic hammers can lead to damage or deformation of castings due to inaccurate impact force or rough operation, thereby reducing product quality and yield.

[0004] For example, patent application number 202210148598.3 discloses a head impact injury testing device based on electromagnetic loading. This device includes an electromagnetic control component, a drive component consisting of a primary coil, a secondary coil, and a loading rod, and an impact head. The drive component includes a buffer block with a groove on its rear side filled with a cushioning medium such as modeling clay. This device uses electromagnetic force as a power source, and the repulsive thrust can be precisely adjusted by regulating the applied voltage. However, the device relies on a cushioning medium such as modeling clay within the buffer block for buffering, which is insufficient for the electromagnetic loading device, resulting in significant limitations in its application. Summary of the Invention

[0005] In order to solve the problems existing in the prior art, the purpose of this invention is to provide an electromagnetic impact device for casting risers and gating systems, which can effectively improve the buffering effect on the electromagnetic loading module and expand the application range of the device.

[0006] The technical solution of this invention is:

[0007] An electromagnetic impact device for casting risers and gating systems includes an impact head, a housing, and a shaft. The shaft is inserted into the housing, and one end of the shaft extends out of the housing and connects to the impact head. The device also includes:

[0008] The electromagnetic loading module includes a primary coil and a secondary coil. The primary coil is mounted on the shaft via a coil base, and the coil base is clearance-fitted with the shaft and slidably connected to the housing. The secondary coil is located between the primary coil and the first mass block and is fixed to the shaft via a coil bracket.

[0009] The first buffer assembly includes a first mass block, a first buffer spring, and a compression part. The first mass block is fixed to the housing and has a through hole on its side wall. The first mass block is fitted onto the shaft through the through hole. The inner wall of the through hole facing the impact head has a boss. The compression part is connected to the shaft. The first buffer spring is located between the boss and the compression part, and the first buffer spring is placed in the through hole and fitted onto the shaft.

[0010] The second buffer assembly is disposed between the coil base and the side wall of the housing away from the impact head, and is used to buffer the primary coil under repulsive force.

[0011] Preferably, the first buffer assembly further includes two buffer pads disposed opposite to each other, both buffer pads being fitted onto the shaft and both buffer pads being disposed between the first mass block and the electromagnetic loading module, one of the buffer pads being fixedly connected to the mass block and the other buffer pad being fixedly connected to the coil support.

[0012] Preferably, the second buffer assembly includes a plurality of shock absorbers, which are arranged in a circumferential array on the side of the coil base away from the secondary coil. The shock absorption direction of the shock absorbers is parallel to the axis of the shaft. One end of each shock absorber is connected to the coil base, and the other end is fixed to the side wall of the housing.

[0013] Preferably, the shock absorber is a damper, and a blind hole is provided on the side wall of the coil base for each damper. One end of the damper is inserted into the blind hole, and the other end is fixed to the side wall of the housing away from the impact head. The depth of the blind hole is less than the length of the damper.

[0014] Preferably, a third buffer assembly is provided between the end of the shaft away from the impact head and the inner wall of the housing, the third buffer assembly comprising:

[0015] The clamping bolt is inserted into the screw hole at the end of the shaft away from the impact head and the two are screwed together;

[0016] The third buffer spring has one end fixed to the clamping bolt and the other end fixed to the inner wall of the housing away from the impact head. The extension and retraction direction of the third spring coincides with the axis of the shaft.

[0017] Preferably, the coil base has an annular groove on the side wall facing the third buffer spring that is adapted to the spring support shell. The spring support shell is engaged in the annular groove. The spring support shell is a hollow cylindrical structure, and the depth of the annular groove is less than the length of the spring support shell. The spring support shell is fitted onto the shaft, and a second buffer spring is provided in the gap between the spring support shell and the shaft. The second buffer spring is also fitted onto the shaft. A bushing is provided at one end of the spring support shell away from the coil base. The bushing is fitted onto the shaft, with one side abutting against the second spring and the other side abutting against the clamping bolt.

[0018] Preferably, the shaft comprises:

[0019] The first mandrel is sequentially inserted into the coil base and the coil support, and one end is connected to the clamping bolt;

[0020] The second spindle has one end inserted into the first mass block and the other end screwed to the impact head through an impact connector.

[0021] An adapter spindle is disposed between the first spindle and the second spindle, and all three are coaxial. The adapter spindle is screwed to the first spindle and the second spindle respectively. One end of the adapter spindle is slidably connected to the through hole of the first mass block and abuts against the first buffer spring.

[0022] Preferably, a second mass block is further provided between the first mass block and the impact joint. The second mass block is fixed to the housing. The second mass block has a first channel at one end facing the first mass block and a second channel at the other end. The diameter of the first channel is smaller than the space of the second channel, and the two are coaxial and connected. The second mandrel passes through the first channel and the second channel, and a linear bearing is embedded in the second channel. The linear bearing is mounted on the second mandrel. The diameter of the first channel is adapted to the second mandrel.

[0023] Preferably, a third mass block is provided between the second mass block and the impact joint. The third mass block is fixed to the housing. A polygonal slide is provided through the third mass block. A polygonal joint is slidably connected in the polygonal slide. One end of the polygonal joint is screwed to the second mandrel, and the other end is screwed to the impact joint.

[0024] Compared with the prior art, the electromagnetic impact device for casting risers of the present invention has the following advantages:

[0025] 1. After the electromagnetic loading module is powered on, the impact force generated instantaneously by the secondary coil drives the shaft to provide impact force to the impact head. At this time, the shaft drives the extrusion part to compress the first buffer spring inside the first mass block. The first buffer spring uses its elastic force to withstand and alleviate the high-speed impact during the cleaning of the riser and gating. The second buffer component is set between the coil base and the side wall of the housing away from the impact head, which can hinder the movement and buffer the repulsive force on the primary coil, reducing the discomfort caused by the recoil force to the operator.

[0026] 2. This device uses electromagnetic loading, which uses primary energy. While improving the energy conversion rate, it generates a greater impact force. The cooperation of the first, second and third buffer components can better withstand and mitigate the high-speed impact during the cleaning of the riser and gating system, reduce the discomfort caused to the operator by the recoil, and the third buffer spring on the third buffer component can absorb the redundant energy during the rebound.

[0027] 3. The overall structure of this device is relatively simple, and the impact components can be easily disassembled and replaced. In addition, the impact force of this device can be precisely adjusted, it is easy to operate, and the vibration is small, achieving the beneficial effects of simultaneously ensuring safety, accuracy, and high cleaning efficiency. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the circuit structure illustrating the working principle in an embodiment of the present invention;

[0029] Figure 2 This is a schematic diagram of the overall structure in an embodiment of the present invention;

[0030] Figure 3 This is a schematic diagram of the exploded structure of the second buffer component in an embodiment of the present invention;

[0031] Figure 4 This is a partial structural diagram of an embodiment of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Impact head; 2. Top cover; 3. Housing; 4. Third mass block; 5. Screw; 6. Second mass block; 7. First mass block; 8. Buffer pad; 9. Adapter spindle; 10. Secondary coil; 11. Primary coil; 12. Spring support shell; 13. Bushing; 14. Clamping bolt; 15. First damper; 16. Coil base; 17. Coil fixing plug; 18. Guide rail; 19. Coil bracket; 20. First spindle; 21. First buffer spring; 22. Second spindle; 23. Linear bearing; 24. Polygonal joint; 25. Impact joint; 26. Second buffer spring; 27. Third buffer spring; 28. Second damper; 29. ​​Third damper. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0035] 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.

[0036] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0037] See Figure 1 , 2 As shown, in order to effectively improve the buffering effect of the electromagnetic loading module and expand the application range of the device, this embodiment provides an electromagnetic impact device for casting risers, including an impact head 1, a housing 3, a shaft, an electromagnetic loading module, a first buffer assembly, and a second buffer assembly.

[0038] The shaft is inserted into the housing 3, with one end extending out of the housing 3 and connecting to the impact head 1. The housing 3 has an opening at one end near the impact head 1 and is equipped with a top cover 2. The top cover 2 is a conical sleeve type with openings at both ends. One end of the opening is screwed into the opening of the housing 3 for easy disassembly.

[0039] The electromagnetic loading module includes a primary coil 11 and a secondary coil 10. The primary coil 11 is mounted on a shaft via a coil base 16 and a coil fixing plug 17. The coil base 16 and the coil fixing plug 17 are clearance-fitted with the shaft and slidably connected to the housing 3. The coil base 16 and the coil fixing plug 17 not only fix the coil but also reduce the impact of electromagnetic force interaction on the coil structure. Preferably, a guide rail 18 is fixed on the inner wall of the housing 3, and both the coil base 16 and the coil fixing plug 17 slide within the guide rail 18, providing support and guidance for the primary coil 11. The secondary coil 10 is located between the primary coil 11 and the first mass block 7 and is fixed to the shaft via a coil bracket 19. Preferably, the coil bracket 19 is fixed to the shaft via a threaded connection, and the coil bracket 19 protects the secondary coil 10.

[0040] The first buffer assembly includes a first mass block 7, a first buffer spring 21, and a compression part. The first mass block 7 is fixed to the housing 3 and has a through hole on its side wall. The first mass block 7 is fitted onto the shaft through the through hole. A boss is provided on the inner wall of the through hole facing the impact head 1. The compression part is connected to the shaft. The first buffer spring 21 is located between the boss and the compression part, and the first buffer spring 21 is placed in the through hole and fitted onto the shaft.

[0041] See Figure 1 As shown, the shaft consists of a first spindle 20, a second spool, and a connecting spindle 9, all three being coaxially aligned. The first spindle 20 is sequentially inserted into the coil base 16 and the coil support 19, with one end connected to the second buffer assembly. One end of the second spindle 22 is inserted into the first mass block 7, and the other end is screwed to the impact head 1 via an impact connector 25. The connecting spindle 9 is positioned between the first spindle 20 and the second spindle 22, all three being coaxial. The connecting spindle 9 is screwed to both the first spindle 20 and the second spindle 22, with one end slidably connected to the through hole of the first mass block 7 and abutting against the first buffer spring 21. In fact, this connecting spindle 9 is the aforementioned extrusion part. Preferably, the first spindle 20, the second spindle 22, and the connecting spindle 9 are all made of 410 stainless steel.

[0042] See Figure 1 As shown, furthermore, to improve the impact buffering of the secondary coil 10, the first buffer assembly also includes two opposing buffer pads 8, disposed between the first mass block 7 and the secondary coil 10. One buffer pad 8 is fitted onto the adapter spindle 9 and fixed to the first mass block 7, while the other buffer pad 8 is fixed to the coil support 19. Preferably, the buffer pads 8 are made of rubber, and each buffer pad 8 can be composed of multiple pads connected by adhesive bonding.

[0043] See Figure 1As shown, a second buffer assembly is further provided between the coil base 16 and the side wall of the housing 3 away from the impact head 1 to buffer the primary coil 11 under repulsive force. Specifically, the second buffer assembly includes multiple damping elements, which are arranged in a circumferential array on the side of the coil base 16 away from the secondary coil 10. The damping direction of the damping elements is parallel to the axis of the shaft. One end of the damping element is connected to the coil base 16, and the other end is fixed to the side wall of the housing 3. The damping elements are dampers, preferably three dampers, with a rotation angle of 120 degrees between two adjacent dampers. The three dampers are respectively designated as the first damper 15, the second damper 28, and the third damper 29. Blind holes are provided on the side wall of the coil base 16 corresponding to the first damper 15, the second damper 28 and the third damper 29. One end of the first damper 15, the second damper 28 and the third damper 29 is inserted into the corresponding blind hole, and the other end is fixed to the side wall of the housing 3 away from the impact head 1. The depth of the blind hole is less than the length of the corresponding first damper 15 or second damper 28 or third damper 29.

[0044] See Figure 1 As shown, furthermore, in order to improve the buffering effect on the primary coil 11 and absorb the redundant energy generated during rebound, a third buffer assembly is provided between the end of the first spindle 20 away from the impact head 1 and the inner wall of the housing 3. The third buffer assembly includes a clamping bolt 14 and a third buffer spring 27. The clamping bolt 14 is inserted into a screw hole opened at the end of the shaft away from the impact head 1 and the two are screwed together; one end of the third buffer spring 27 is fixed to the clamping bolt 14, and the other end is fixed to the inner wall of the housing 3 away from the impact head 1, and the extension and contraction direction of the third spring coincides with the axis of the shaft. The third buffer assembly also includes a spring support shell 12, a second buffer spring 26, and a bushing 13. The coil base 16 has an annular groove on its side wall facing the third buffer spring 27 that is adapted to the spring support shell 12. The spring support shell 12 is a hollow cylindrical structure, with one end of it being fitted into the annular groove. The depth of the annular groove is less than the length of the spring support shell 12. The spring support shell 12 is fitted onto the first spindle 20, and the second buffer spring 26 is provided in the gap between the spring support shell 12 and the first spindle 20. The second buffer spring 26 is also fitted onto the first spindle 20. The end of the spring support shell 12 away from the coil base 16 has a bushing 13, which is fitted onto the first spindle 20. One side of the bushing abuts against the second spring, and the other side abuts against the clamping bolt 14.

[0045] See Figure 1As shown, furthermore, to stabilize the impact force and ensure the stability of the extension and retraction of the first buffer spring 21, the second buffer spring 26, and the third buffer spring 27, thereby improving the buffering effect, a second mass block 6 is also provided between the first mass block 7 and the impact joint 25. The second mass block 6 is fixed to the housing 3. The second mass block 6 has a first channel at one end facing the first mass block 7 and a second channel at the other end. The diameter of the first channel is smaller than the space of the second channel, and the two are coaxial and connected. The second spindle 22 passes through the first channel and the second channel, and a linear bearing 23 is embedded in the second channel. The linear bearing 23 is mounted on the second spindle 22, and the diameter of the first channel is adapted to the second spindle 22. The linear bearing 23 makes it less likely for the shaft to generate radial errors during axial movement, resulting in higher guiding accuracy.

[0046] See Figure 1 As shown, a third mass block 4 is also provided between the second mass block 6 and the impact joint 25. The third mass block 4 is fixed to the housing 3. Preferably, the first mass block 7, the second mass block 6, and the third mass block 4 are all detachably connected to the side wall of the housing 3 by multiple screws 5, which facilitates maintenance and replacement. The third mass block 4 has a polygonal slide rail through it. A polygonal joint 24 is slidably connected in the polygonal slide rail. One end of the polygonal joint 24 is screwed to the second mandrel 22, and the other end is screwed to the impact joint 25. Preferably, the polygonal slide rail adopts an internal hexagonal channel, and the polygonal joint 24 adopts an external hexagonal joint. Before the impact cleaning of the riser and gating gate begins, there is a certain safety distance between the secondary coil 10 assembly and the primary coil 11 assembly. Due to the influence of the third mass block 4 and the external hexagonal joint, the shaft can only move in the left and right directions. The external hexagonal joint cannot rotate relative to the second mandrel 22 and the impact joint 25, which can ensure that the shaft will not loosen the threaded connection between the mandrels due to the replacement of the impact head 1.

[0047] Furthermore, the weight of the middle position of the loading device is increased by using the second mass block 6 and the first mass block 7. The upper part of the third mass block 4 is hollow, which reduces the weight of the device near the impact head 1 and avoids the phenomenon that the center of gravity is at both ends of the device, making the operator's holding position more comfortable. A heat dissipation hole is opened on the right end of the housing 3 to prevent the coil from overheating.

[0048] The working principle of this device is as follows:

[0049] like Figure 1As shown, G is the energy storage power supply, and S is the trigger switch. First, the energy storage power supply is charged. When the set voltage value is reached, charging stops, and a trigger signal is sent to the trigger switch, activating the coil circuit. The energy storage power supply G discharges instantaneously, generating a large pulse current in the primary coil 11. The secondary coil 10 induces a circular current in the opposite direction. This circular current interacts with the magnetic field between the two coils to generate an electromagnetic force. This force drives the secondary coil 10 forward. The secondary coil 10, using a shaft, causes the impact joint 25 to move synchronously, providing an axial repulsive force to the impact head 1, thereby impacting the casting riser and completing one cleaning process. The primary coil 11 and the secondary coil 10 are coaxial and of the same diameter. This structure not only ensures tight magnetic coupling and high conversion efficiency but also, due to its axial symmetry, provides the coil with good mechanical strength to resist electromagnetic forces, making the mechanical fixing structure easy to implement. Furthermore, by adjusting the charging voltage, different magnitudes of electromagnetic forces can be generated to drive the coils and achieve the impact. During the impact, the first buffer spring 21 and the buffer pad 8 can reduce the instantaneous impact force and protect the safety of the secondary coil 10. The bushing 13 can buffer the high-speed loading by squeezing the second buffer spring 26 and stretching the third buffer spring 27. After the impact head 1 hits the casting riser, the loading device will rebound to a certain extent. At this time, the third buffer spring 27 can absorb the redundant energy during the rebound and protect the primary coil 11.

[0050] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A casting ingate electromagnetic impact device, comprising an impact head (1), a shell (3) and a shaft, the shaft is inserted into the shell (3), one end of the shaft extends out of the shell (3) and is connected with the impact head (1), characterized in that, Also include: Electromagnetic loading module, including the primary coil (11) and the secondary coil (10), the primary coil (11) is sleeved on the shaft by the coil base (16), and the coil base (16) is in clearance fit with the shaft, and is in sliding connection with the shell (3);The secondary coil (10) is located between the primary coil (11) and the first mass (7) and is fixed with the shaft through the coil support (19); The first buffer assembly includes a first mass (7), a first buffer spring (21) and a pressing part, the first mass (7) is fixed with the shell (3) and a through hole is formed in the side wall, the first mass (7) is sleeved on the shaft through the through hole, the inner wall of the side wall facing the impact head (1) is provided with a boss, the pressing part is connected to the shaft, the first buffer spring (21) is located between the boss and the pressing part, and the first buffer spring (21) is placed in the through hole and sleeved on the shaft; The second buffer assembly is arranged between the coil base (16) and the side wall of the shell (3) away from the impact head (1), and is used for buffering the primary coil (11) under the repulsion; The third buffer assembly is arranged between the end of the shaft away from the impact head (1) and the inner wall of the shell (3), and the third buffer assembly comprises: Clamping bolt (14), inserted into the threaded hole formed in the end of the shaft away from the impact head (1) and screwed together; The third buffer spring (27) is fixed at one end of the clamping bolt (14), and the other end is fixed with the inner wall of the shell (3) away from the impact head (1), and the extension direction of the third buffer spring (27) coincides with the axis of the shaft; The side wall of the coil base (16) facing the third buffer spring (27) is provided with an annular groove matched with the spring support shell (12), the spring support shell (12) is inserted into the annular groove, the spring support shell (12) is a hollow cylindrical structure, and the depth of the annular groove is less than the length of the spring support shell (12), the spring support shell (12) is sleeved on the shaft, and the spring support shell (12) is provided with a second buffer spring (26) in the clearance between the spring support shell (12) and the shaft, the second buffer spring (26) is also sleeved on the shaft, the end of the spring support shell (12) away from the coil base (16) is provided with a shaft sleeve (13), the shaft sleeve (13) is sleeved on the shaft, one side of the shaft sleeve (13) abuts against the second buffer spring (26), and the other side abuts against the clamping bolt (14); The shaft comprises: The first core shaft (20) is inserted into the coil base (16) and the coil support (19) in sequence, and one end is connected with the clamping bolt (14); The second core shaft (22) is inserted into the first mass (7) at one end and is screwed with the impact head (1) through the impact joint (25) at the other end. An adapter mandrel (9) is coaxially arranged between the first mandrel (20) and the second mandrel (22), and is screwed with the first mandrel (20) and the second mandrel (22) respectively. One end of the adapter mandrel (9) is slidingly connected in a through hole of the first mass block (7) and abuts against the first buffer spring (21). The adapter mandrel (9) is the extrusion part.

2. A device for electromagnetic impact of a casting sprue according to claim 1, characterized in that The first buffer assembly further comprises two oppositely arranged buffer pads (8). The two buffer pads (8) are sleeved on the shaft rod, and the two buffer pads (8) are arranged between the first mass block (7) and the secondary coil (10). One of the buffer pads (8) is fixedly connected with the first mass block (7), and the other buffer pad (8) is fixedly connected with the coil support (19).

3. The electromagnetic shock device for casting sprue according to claim 1, wherein The second buffer assembly comprises a plurality of shock absorbers. The plurality of shock absorbers are circumferentially arranged on a side of the coil base (16) away from the secondary coil (10). The shock absorbing direction of the shock absorber is parallel to the axis of the shaft rod. One end of the shock absorber is connected with the coil base (16), and the other end is fixed with the side wall of the shell (3).

4. A device for electromagnetic impact of a casting sprue according to claim 3, characterized in that The shock absorber is a damper. A blind hole is formed in the side wall of the coil base (16) corresponding to each damper. One end of the damper is inserted into the blind hole, and the other end is fixed with the side wall of the shell (3) away from the impact head (1). The depth of the blind hole is less than the length of the damper.

5. The electromagnetic shock device for casting sprue according to claim 1, wherein A second mass block (6) is further arranged between the first mass block (7) and the impact joint (25). The second mass block (6) is fixed with the shell (3). A first hole is formed in one end of the second mass block (6) facing the first mass block (7), and a second hole is formed in the other end. The hole diameter of the first hole is smaller than the space of the second hole, and the two holes are coaxial and communicate with each other. The second mandrel (22) passes through the first hole and the second hole, and a linear bearing (23) is embedded in the second hole. The linear bearing (23) is sleeved on the second mandrel (22). The hole diameter of the first hole is matched with the second mandrel (22).

6. A device for electromagnetic impact of a casting sprue according to claim 5, characterized in that A third mass block (4) is further arranged between the second mass block (6) and the impact joint (25). The third mass block (4) is fixed with the shell (3). A polygonal slide is formed through the third mass block (4). A polygonal joint (24) is slidingly connected in the polygonal slide. One end of the polygonal joint (24) is screwed with the second mandrel (22), and the other end is screwed with the impact joint (25).

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