An oil press

Abstract

The invention discloses an oil press, belonging to the technical field of oil press equipment. The pressing screw shaft is a stamping type pressing screw shaft, which includes a front-stage pressing screw shaft, a secondary stamping device and a rear-stage pressing screw shaft. The front-stage pressing screw shaft and the rear-stage pressing screw shaft are formed by radial segmentation of the pressing screw shaft. The front section of the pressing screw shaft after segmentation is the front-stage pressing screw shaft, and the rear section of the pressing screw shaft after segmentation is the rear-stage pressing screw shaft. The secondary stamping device is fixed between the front-stage pressing screw shaft and the rear-stage pressing screw shaft. The secondary stamping device is provided with more than two spiral secondary stamping channels, and the front port of each secondary stamping channel is connected to the rear port of the front-stage spiral oil pressing channel, and the rear port of each secondary stamping channel is connected to the front port of the rear-stage spiral oil pressing channel; the spiral angle of the side wall of each secondary stamping channel is smaller than the spiral angle of the pressing screw shaft. It has the characteristics of high oil pressing efficiency, small size, and easy disassembly and maintenance.

Description

Technical Field

[0001] The invention relates to the technical field of oil pressing equipment. Background Art

[0002] The oil press is a kind of edible oil preparation equipment. It uses physical methods to squeeze the oil crops through the oil pressing structure to separate the oil from the oil crops. The spiral shaft rotates so that the spiral blades push the oil crops forward. The diameter of the spiral shaft gradually increases from front to back. During the forward movement of the oil crops, they are squeezed between the spiral shaft and the pressing bars arranged around the spiral shaft, and the oil is squeezed out from the gaps between the pressing bars.

[0003] The spiral shaft currently used is formed by a spiral blade spirally wound around the shaft from front to back. During the oil pressing process, since the spiral angle of the spiral blade does not change much, the squeezing force exerted on the oil crop at each part of the spiral shaft is basically the same. However, it is not difficult to understand that as the oil crop is continuously squeezed and the oil continues to overflow, the oil crop at the rear of the spiral shaft has less oil content, and the oil pressing effect will become worse and worse with the same squeezing force, which affects the efficiency of oil pressing. At the same time, the oil crop at the rear of the spiral shaft cannot reach the required squeezing force, which will cause power consumption and waste of energy. In order to ensure the loose oil content of the cake, it is necessary to increase the length of the spiral shaft, which will increase the volume of the oil press and the power consumption will also increase accordingly. An oversized oil press will also bring difficulties to the subsequent maintenance and repair work. If the spiral angle of the spiral blade is changed to adapt to the squeezing force required by the oil crops behind the spiral shaft, the squeezing force on the oil crops in front of the spiral shaft will be too large, which will also cause energy waste. In short, in the oil pressing process, the squeezing force required for the oil crops at the front and back positions of the spiral shaft is different, and reasonable matching is needed to ensure the loose oil content of the cake while reducing energy consumption and miniaturizing the equipment. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide an oil press, which has the characteristics of high oil pressing efficiency, small size, easy disassembly and maintenance, etc.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] An oil press comprises a frame and an oil pressing device mounted on the frame, the oil pressing device comprises a pressing screw shaft and a pressing chamber, the pressing chamber comprises a pressing cage and pressing bars, the pressing bars are supported, arranged and fixed by the pressing cage to form a pressing screw shaft adapting chamber, the pressing cage is fixed to the frame; the pressing screw shaft is rotatably connected to the frame, the shaft body of the pressing screw shaft located in the pressing screw shaft adapting chamber forms an oil pressing structure with the pressing screw shaft adapting chamber: the spiral grooves formed between adjacent spiral sheets of the pressing screw shaft and the inner wall of the pressing screw shaft adapting chamber form a spiral oil pressing channel, the cross-sectional area of ​​the spiral oil pressing channel gradually decreases from front to back, and the gaps between the pressing bars in the pressing screw shaft adapting chamber form a spiral oil pressing channel. The spiral oil pressing passage is provided with a residue outlet at the end thereof; when the pressing screw shaft rotates, the spiral blades push the oil crop to move from front to back in the oil pressing passage, and the gradually smaller oil pressing passage produces a pressing effect on the oil crop, so that the crop oil component in the oil crop is pressed out and squeezed out from the oil pressing hole, and the crop residue after squeezing is discharged from the residue outlet at the end of the spiral oil pressing passage. In the oil pressing structure, the pressing screw shaft is a stamping pressing screw shaft, which includes a front-stage pressing screw shaft, a secondary stamping device and a rear-stage pressing screw shaft. The front-stage pressing screw shaft and the rear-stage pressing screw shaft are formed by radially dividing the pressing screw shaft, and the front-stage portion of the pressing screw shaft after division is the front-stage pressing screw shaft. The pressing screw shaft, after the splitting, the rear section of the pressing screw shaft is the rear section pressing screw shaft, the spiral oil pressing channel located at the front section pressing screw shaft is the front section spiral oil pressing channel, and the spiral oil pressing channel located at the rear section pressing screw shaft is the rear section spiral oil pressing channel; the secondary punching device is fixed between the front section pressing screw shaft and the rear section pressing screw shaft, and the secondary punching device is provided with more than two spiral secondary punching channels, and the specific structure is: the secondary punching device is provided with a plurality of spiral secondary punching channel side walls coaxial with the pressing screw shaft, and the adjacent secondary punching channel side walls and the secondary punching channel bottom wall located between them and the inner wall of the pressing screw shaft matching cavity form The spiral channel is a secondary punching channel, and the front port of each secondary punching channel is connected to the rear port of the front spiral oil pressing channel, and the rear port of each secondary punching channel is connected to the front port of the rear spiral oil pressing channel; the spiral angle of the side wall of each secondary punching channel is smaller than the spiral angle of the pressing screw shaft, so that the secondary punching channel can increase the propulsion speed of the oil crop at the same rotation speed. When the oil crop enters each secondary punching channel from the rear port of the front spiral oil pressing channel, each secondary punching channel quickly propels it into the rear spiral oil pressing channel, so that the rear spiral oil pressing channel increases the pressing force on the oil crop to improve the oil pressing rate.

[0007] The present invention is further improved in that:

[0008] The secondary punching device is provided with 3 to 8 secondary punching channels, and the helix angle of each secondary punching channel is 8° to 30° smaller than the helix angle of the squeezing screw shaft.

[0009] The specific structure of each spiral secondary punching channel is as follows: the side wall of the secondary punching channel is a cylindrical spiral body with equal diameter, which is used to cooperate with the inner wall of the matching cavity of the pressing screw shaft to make the adjacent secondary punching channels relatively closed, and the bottom wall of the secondary punching channel includes an oil crop pushing surface and an oil crop grinding surface, and the oil crop pushing surface and the oil crop grinding surface are both spiral surfaces, and the front end edge of the oil crop pushing surface is connected with the rear end edge of the secondary punching channel side wall at the front end of the secondary punching channel, and the rear end edge of the oil crop pushing surface is connected with the front end edge of the oil crop grinding surface, and the rear end edge of the oil crop grinding surface is connected with the front end edge of the secondary punching channel side wall at the rear end of the secondary punching channel, and the connection point between the rear end edge of the oil crop pushing surface and the front end edge of the oil crop grinding surface is the lowest point of the bottom wall of the secondary punching channel, and the slope of the oil crop pushing surface is steeper than that of the oil crop grinding surface, so that during the rotation of the pressing screw shaft, the oil crop pushing surface with a steeper slope is convenient for pushing the oil crop to move forward. The oil crop grinding surface with a gentle slope has a better grinding and squeezing effect on the oil crops, so as to improve the oil extraction rate, because the gap between it and the inner wall of the matching cavity of the pressing screw shaft gradually decreases from front to back.

[0010] The structure of the stamping type screw pressing shaft is as follows: it includes a central shaft, which is provided with a bearing seat mounting part, a screw pressing mounting part and a spline groove for transmission connection with the gearbox in sequence from front to back; the bearing seat mounting part is used to install the bearing seat so as to be fixedly connected with the frame, and is provided with a bearing sleeve fixing thread, a bearing inner ring assembly shaft and a bearing sleeve positioning shoulder in sequence from front to back; the screw pressing mounting part is provided with a screw pressing fixing thread, a screw pressing assembly shaft and a screw pressing positioning shoulder in sequence from front to back, a keyway is provided on the screw pressing assembly shaft, the front-stage screw pressing shaft, the secondary stamping device and the rear-stage screw pressing shaft are all provided with shaft holes and keyways matched with the screw pressing assembly shaft, the front-stage screw pressing shaft, the secondary stamping device and the rear-stage screw pressing shaft are circumferentially fixed to the screw pressing assembly shaft through the keyway connection, the screw pressing fixing nut is screwed into the screw pressing fixing thread, and the front-stage screw pressing shaft, the secondary stamping device and the rear-stage screw pressing shaft are fixed between the screw pressing fixing nut and the screw pressing positioning shoulder.

[0011] The beneficial effects of adopting the above technical solution are:

[0012] The present invention improves the pressing screw shaft into a stamping type pressing screw shaft, wherein the secondary stamping device is provided with more than two spiral secondary stamping channels, and the spiral angle of the side wall of each secondary stamping channel is smaller than the spiral angle of the pressing screw shaft, so that the secondary stamping channel can increase the propulsion speed of the oil crop at the same rotation speed. When the oil crop enters each secondary stamping channel from the rear port of the front spiral oil pressing channel, each secondary stamping channel quickly propels it into the rear spiral oil pressing channel, so that the rear spiral oil pressing channel increases the pressing force on the oil crop, thereby improving the oil pressing rate.

[0013] It has the characteristics of high oil pressing efficiency, small size, and easy disassembly and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the present invention;

[0015] Figure 2 yes Figure 1 Schematic diagram of the structure of the middle punch press screw shaft and press chamber;

[0016] Figure 3 yes Figure 2 Left view of;

[0017] Figure 4 yes Figure 3 AA section view;

[0018] Figure 5 yes Figure 4 Schematic diagram of the local structure;

[0019] Figure 6 yes Figure 5 The structural diagram of the secondary stamping device;

[0020] Figure 7 yes Figure 6 Schematic diagram of the structure after the AA section view is expanded.

[0021] In the attached drawings: 1. frame; 2. pressing cage; 3. pressing bar; 4. spiral sheet; 5. front section pressing screw shaft; 6. secondary punching device; 7. rear section pressing screw shaft; 8. front section spiral oil pressing channel; 9. rear section spiral oil pressing channel; 10. side wall of secondary punching channel; 11. secondary punching channel; 12. oil crop pushing surface; 13. oil crop grinding surface; 14. pressing screw assembly shaft; 15. spline groove; 16. bearing inner ring assembly shaft; 17. pressing screw fixing nut; 18. bearing sleeve fixing nut; 19. bearing seat; 20. peanut inlet; 21. peanut residue outlet; 22. motor. DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, and bonding in the prior art, which will not be described in detail here.

[0024] Depend on Figures 1 to 7As can be seen from the embodiment shown, this embodiment includes a frame 1 and an oil pressing device installed on the frame 1, the oil pressing device includes a pressing screw shaft and a pressing chamber, the pressing chamber includes a pressing cage 2 and pressing bars 3, the pressing bars 3 are supported, arranged and fixed by the pressing cage 2 to form a pressing screw shaft adaptation chamber, and the pressing cage 2 is fixed to the frame 1; the pressing screw shaft is rotatably connected to the frame 1, and the shaft body of the pressing screw shaft located in the pressing screw shaft adaptation chamber forms an oil pressing structure with the pressing screw shaft adaptation chamber: the spiral grooves formed between adjacent spiral sheets 4 of the pressing screw shaft are combined with the inner wall of the pressing screw shaft adaptation chamber to form a spiral oil pressing channel, the cross-sectional area of ​​the spiral oil pressing channel gradually decreases from front to back, the gaps between the pressing bars 3 in the pressing screw shaft adaptation chamber form oil pressing outlets, and the spiral oil pressing channel The end is provided with an annular residue outlet coaxial with the pressing screw shaft; when the pressing screw shaft rotates, the spiral blade 4 pushes the oil crop to move from front to back in the oil pressing channel, and the gradually smaller oil pressing channel produces a pressing effect on the oil crop, so that the crop oil component in the oil crop is pressed out and squeezed out from the oil pressing outlet, and the crop residue after squeezing is discharged from the residue outlet at the end of the spiral oil pressing channel. In the oil pressing structure, the pressing screw shaft is a stamping pressing screw shaft, which includes a front-stage pressing screw shaft 5, a secondary stamping device 6 and a rear-stage pressing screw shaft 7. The front-stage pressing screw shaft 5 and the rear-stage pressing screw shaft 7 are formed by radial segmentation of the pressing screw shaft. The front section of the pressing screw shaft after segmentation is the front-stage pressing screw shaft 5, and the rear section of the pressing screw shaft after segmentation is the rear-stage pressing screw shaft 7. The spiral oil pressing channel of the screw shaft 5 is the front-stage spiral oil pressing channel 8, and the spiral oil pressing channel located at the rear-stage spiral oil pressing channel 7 is the rear-stage spiral oil pressing channel 9; the secondary punching device 6 is fixed between the front-stage spiral oil pressing shaft 5 and the rear-stage spiral oil pressing shaft 7, and the secondary punching device 6 is provided with six spiral secondary punching channels 11, and the specific structure is: the secondary punching device 6 is provided with a plurality of spiral secondary punching channel side walls 10 coaxial with the pressing screw shaft, and the spiral channel formed between the adjacent secondary punching channel side walls 10 and the secondary punching channel bottom wall located therebetween and the inner wall of the screw shaft adapter cavity is the secondary punching channel 11, and the front port of each secondary punching channel 11 is connected to the rear port of the front-stage spiral oil pressing channel 8 , the rear port of each secondary punching channel 11 is connected with the front port of the rear-stage spiral oil pressing channel 9; the average diameter of the bottom wall of the secondary punching channel is the same as the average diameter of the bottom wall of the rear port of the front-stage spiral oil pressing channel 8 and the bottom wall of the front port of the rear-stage spiral oil pressing channel 9, and the helix angle of each secondary punching channel side wall 10 is smaller than the helix angle of the pressing screw shaft, so that the secondary punching channel 11 can increase the propulsion speed of the oil crop at the same rotation speed. When the oil crop enters each secondary punching channel 11 from the rear port of the front-stage spiral oil pressing channel 8, each secondary punching channel 11 quickly propels it into the rear-stage spiral oil pressing channel 9, so that the rear-stage spiral oil pressing channel 9 increases the pressing force on the oil crop to improve the oil pressing rate.

[0025] The secondary punching device 6 is provided with 3 to 8 secondary punching channels 11, the helix angle of each secondary punching channel 11 is 64.01°, and the helix angle of the pressing screw shaft is 77°.

[0026] The specific structure of each spiral secondary punching channel 11 is as follows: the side wall 10 of the secondary punching channel is a cylindrical spiral body with equal diameter, which is used to cooperate with the inner wall of the adapting cavity of the pressing screw shaft to make the adjacent secondary punching channels 11 relatively closed, and the bottom wall of the secondary punching channel includes an oil crop pushing surface 12 and an oil crop grinding surface 13, and the oil crop pushing surface 12 and the oil crop grinding surface 13 are both spiral surfaces, and the front end edge of the oil crop pushing surface 12 is connected with the rear end edge of the secondary punching channel side wall 10 at the front end of the secondary punching channel 11, and the oil crop pushing surface 12 is connected with the rear end edge of the secondary punching channel side wall 10 at the front end of the secondary punching channel 11. The rear edge of the moving surface 12 is connected with the front edge of the oil crop grinding surface 13, and the rear edge of the oil crop grinding surface 13 is connected with the front edge of the secondary punching channel side wall 10 at the rear end of the secondary punching channel 11. The connection point between the rear edge of the oil crop pushing surface 12 and the front edge of the oil crop grinding surface 13 is the lowest point of the bottom wall of the secondary punching channel 11. The slope of the oil crop pushing surface 12 is steeper than that of the oil crop grinding surface 13, so that during the rotation of the squeezing screw shaft, the oil crop pushing surface 12 with a steeper slope is convenient for pushing the oil crop forward. The oil crop grinding surface 13 with a gentler slope has a better grinding and squeezing effect on the oil crop because the gap between it and the inner wall of the squeezing screw shaft matching cavity gradually decreases from front to back, so as to improve the oil pressing rate.

[0027] The structure of the stamping type screw pressing shaft is as follows: it includes a central shaft, which is provided with a bearing seat mounting part, a screw pressing mounting part and a spline groove 15 for transmission connection with the gearbox in sequence from front to back; the bearing seat mounting part is used to install the bearing seat 19 so as to be fixedly connected with the frame 1, and it is provided with a bearing sleeve fixing thread, a bearing inner ring assembly shaft 16 and a bearing sleeve positioning shoulder in sequence from front to back, the inner ring of the bearing is assembled on the bearing inner ring assembly shaft 16, and the bearing sleeve fixing nut 18 is screwed into the bearing sleeve fixing thread to fix the bearing seat 19 between the bearing sleeve fixing nut 18 and the bearing sleeve positioning shoulder; the screw pressing mounting part is used to install the bearing seat 19 so as to be fixedly connected with the frame 1, and the bearing seat fixing thread, the bearing inner ring assembly shaft 16 and the bearing sleeve positioning shoulder are arranged in sequence from front to back, and the inner ring of the bearing is assembled on the bearing inner ring assembly shaft 16, and the bearing sleeve fixing nut 18 is screwed into the bearing sleeve fixing thread to fix the bearing seat 19 between the bearing sleeve fixing nut 18 and the bearing sleeve positioning shoulder; The pressing screw fixing thread, the pressing screw assembly shaft 14 and the pressing screw positioning shoulder are provided in sequence from front to back. The pressing screw assembly shaft 14 is provided with a keyway. The front-stage pressing screw shaft 5, the secondary punching device 6 and the rear-stage pressing screw shaft 7 are all provided with shaft holes and keyways matched with the pressing screw assembly shaft 14. The front-stage pressing screw shaft 5, the secondary punching device 6 and the rear-stage pressing screw shaft 7 are circumferentially fixed to the pressing screw assembly shaft 14 through the keyway connection. The pressing screw fixing nut 17 is screwed into the pressing screw fixing thread to fix the front-stage pressing screw shaft 5, the secondary punching device 6 and the rear-stage pressing screw shaft 7 between the pressing screw fixing nut 17 and the pressing screw positioning shoulder.

Claims

1. An oil press, comprising a frame (1) and an oil pressing device mounted on the frame (1), the oil pressing device comprising a pressing screw shaft and a pressing chamber, the pressing chamber comprising a pressing cage (2) and pressing bars (3), the pressing bars (3) being supported, arranged and fixed by the pressing cage (2) to form a pressing screw shaft adapting chamber, the pressing cage (2) being fixed to the frame (1); the pressing screw shaft being rotatably connected to the frame (1), the shaft body of the pressing screw shaft located in the pressing screw shaft adapting chamber forming an oil pressing structure with the pressing screw shaft adapting chamber; the spiral grooves formed between adjacent spiral sheets (4) of the pressing screw shaft being connected to the pressing screw shaft adapting chamber; The inner wall of the screw shaft adapting cavity is combined to form a spiral oil pressing channel, the cross-sectional area of ​​the spiral oil pressing channel gradually decreases from front to back, the gap between the pressing bars (3) in the screw shaft adapting cavity forms an oil pressing outlet, and a slag outlet is provided at the end of the spiral oil pressing channel; when the screw shaft rotates, the spiral blade (4) pushes the oil crop to move from front to back in the oil pressing channel, and the gradually decreasing oil pressing channel produces a pressing effect on the oil crop, so that the crop oil component in the oil crop is pressed out and squeezed out from the oil pressing outlet, and the crop residue after squeezing is discharged from the slag outlet at the end of the spiral oil pressing channel, characterized in that: In the oil pressing structure, the pressing screw shaft is a stamping type pressing screw shaft, which includes a front-stage pressing screw shaft (5), a secondary stamping device (6) and a rear-stage pressing screw shaft (7). The front-stage pressing screw shaft (5) and the rear-stage pressing screw shaft (7) are formed by radial segmentation of the pressing screw shaft. After segmentation, the front-stage portion of the pressing screw shaft is the front-stage pressing screw shaft (5), and the rear-stage portion of the pressing screw shaft is the rear-stage pressing screw shaft (7). The spiral oil pressing channel located at the front-stage pressing screw shaft (5) is the front-stage spiral pressing screw shaft. The oil channel (8) is a spiral oil pressing channel located on the rear-stage pressing screw shaft (7) as the rear-stage spiral oil pressing channel (9); the secondary punching device (6) is fixed between the front-stage pressing screw shaft (5) and the rear-stage pressing screw shaft (7); the secondary punching device (6) is provided with more than two spiral secondary punching channels (11); the specific structure is as follows: the secondary punching device (6) is provided with a plurality of spiral secondary punching channel side walls (10) coaxial with the pressing screw shaft, The spiral channel formed between the adjacent secondary punching channel side walls (10) and the secondary punching channel bottom wall located therebetween and the inner wall of the screw pressing shaft adapting cavity is the secondary punching channel (11); the front port of each secondary punching channel (11) is connected to the rear port of the front-stage spiral oil pressing channel (8), and the rear port of each secondary punching channel (11) is connected to the front port of the rear-stage spiral oil pressing channel (9); the spiral angle of each secondary punching channel side wall (10) is smaller than the spiral angle of the screw pressing shaft, so that the secondary punching channel (11) increases the propulsion speed of the oil crop at the same rotation speed; when the oil crop enters each secondary punching channel (11) from the rear port of the front-stage spiral oil pressing channel (8), each secondary punching channel (11) quickly propels it into the rear-stage spiral oil pressing channel (9), so that the rear-stage spiral oil pressing channel (9) increases the pressing force on the oil crop, thereby improving the oil pressing rate.

2. An oil press according to claim 1, characterized in that: The secondary punching device (6) is provided with 3 to 8 secondary punching channels (11), and the helical angle of each secondary punching channel (11) is 8° to 30° smaller than the helical angle of the squeezing screw shaft.

3. An oil press according to claim 1 or 2, characterized in that: The specific structure of each spiral secondary punching channel (11) is as follows: the side wall (10) of the secondary punching channel is a cylindrical spiral body with equal diameter, which is used to cooperate with the inner wall of the matching cavity of the pressing screw shaft to make the adjacent secondary punching channels (11) relatively closed; the bottom wall of the secondary punching channel includes an oil crop pushing surface (12) and an oil crop grinding surface (13); the oil crop pushing surface (12) and the oil crop grinding surface (13) are both spiral surfaces; the front end edge of the oil crop pushing surface (12) is connected with the rear end edge of the secondary punching channel side wall (10) at the front end of the secondary punching channel (11); the rear end edge of the oil crop pushing surface (12) is connected with the front end edge of the oil crop grinding surface (13); the oil crop pushing surface (12) is connected with the front end edge of the oil crop grinding surface (13); The rear edge of the crop grinding surface (13) is connected to the front edge of the secondary punching channel side wall (10) at the rear end of the secondary punching channel (11); the connection point between the rear edge of the oil crop pushing surface (12) and the front edge of the oil crop grinding surface (13) is the lowest point of the bottom wall of the secondary punching channel (11); the slope of the oil crop pushing surface (12) is steeper than the slope of the oil crop grinding surface (13), so that during the rotation of the squeezing screw shaft, the oil crop pushing surface (12) with a steeper slope is convenient for pushing the oil crop forward; and the oil crop grinding surface (13) with a gentler slope has a gap with the inner wall of the squeezing screw shaft matching cavity that gradually decreases from front to back, so that it has a better grinding and squeezing effect on the oil crop, thereby improving the oil extraction rate.

4. An oil press according to claim 3, characterized in that: The punching type screw pressing shaft structure comprises: comprising a central shaft, wherein the central shaft is provided with a bearing seat mounting portion, a screw pressing mounting portion and a spline groove (15) for transmission connection with a gearbox in sequence from front to back; the bearing seat mounting portion is used to mount a bearing seat (19) so as to be fixedly connected with the frame (1), and is provided with a bearing sleeve fixing thread, a bearing inner ring assembly shaft (16) and a bearing sleeve positioning shoulder in sequence from front to back; the screw pressing mounting portion is provided with a screw pressing thread, a screw pressing mounting shaft (14) and a screw pressing positioning shoulder in sequence from front to back, and a key groove is provided on the screw pressing mounting shaft (14). The front-stage squeezing screw shaft (5), the secondary punching device (6) and the rear-stage squeezing screw shaft (7) are all provided with shaft holes and keyways that are compatible with the squeezing screw assembly shaft (14). The front-stage squeezing screw shaft (5), the secondary punching device (6) and the rear-stage squeezing screw shaft (7) are circumferentially fixed to the squeezing screw assembly shaft (14) through the keyways. The squeezing screw fixing nut (17) is screwed into the squeezing screw fixing thread to fix the front-stage squeezing screw shaft (5), the secondary punching device (6) and the rear-stage squeezing screw shaft (7) between the squeezing screw fixing nut (17) and the squeezing screw positioning shoulder.

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