CN110843000B - Paper tube cutting machine - Google Patents

Abstract

The invention discloses a paper tube cutting machine, which comprises a frame and a control system, wherein one end of the frame is provided with a mandrel fixing device and a driving device, and the other end of the frame is provided with a clamping rotating device; the central roller is arranged at the central position of the mandrel fixing device, N mandrels are arranged at the edge of the central roller, N is an even number, and every two mandrels form a group of mandrel groups; the machine frame is also provided with a horizontal moving device, and a cutter device is arranged above the horizontal moving device. The mandrel fixing device can effectively fix the mandrel and avoid shaking of the mandrel. Simultaneously the outside of the mandrel is fixed through the adjusting seat, and the axis of the mandrel can be finely adjusted through the central adjusting screw, so that the mandrel can be fixed to avoid shaking, the axis of the mandrel can be adjusted, the axis of the mandrel is ensured to meet the requirement of collimation degree in the processing process, and the processing quality is improved. The invention has 4 groups of 8 mandrels, each group has own functions, and the processing efficiency can be improved by more than one time by matching with two cutters.

Description

Paper tube cutting machine

Technical Field

The invention relates to the technical field of paper tube processing equipment, in particular to a paper tube cutting machine for cutting a paper tube.

Background

Paper tubes are a common product in daily life, and have wide application, such as products of adhesive tapes, roll paper, plastic films and the like, and the paper tubes are used as inner cores. When the paper tube is manufactured, paper with certain thickness and hardness is matched with glue, hard paper is wound into the paper tube on special tube rolling equipment, and the paper tube is required to be cut into long paper tubes with the length of one meter to a plurality of meters in the manufacturing process because the winding process is continuous. At this time, the paper tube is long and cannot be directly applied to products such as adhesive tapes, roll paper and the like, so that special paper tube cutting equipment is also required to cut the long paper tube into small paper tubes with specified lengths. The prior art paper tube cutting apparatus has many technical problems.

First, among the prior art, paper tube cutting equipment only has one or two dabbers, and dabber diameter slightly is less than the internal diameter of paper tube, and paper tube suit is at dabber, can not take place the radial swing of by a wide margin. The cutter of the paper tube cutting device cuts the paper tube into small paper tubes with a certain length, and after one long paper tube is cut, a worker sleeves the other long paper tube on the mandrel and then cuts the paper tube. Because the existing paper tube cutting equipment only has one mandrel for cutting, or two mandrels are alternately cut, when the existing paper tube cutting equipment is used for processing paper tubes with small diameters, the processing efficiency is very low.

Secondly, when the cutting equipment works, the paper tube rotates at a high speed under the drive of the chuck, the cutter approaches to the paper tube and is tangent to the paper tube rotating at the high speed, the paper tube is cut off by utilizing the friction force between the cutter and the paper tube, but the cutter cannot confirm when the cutter cuts off the paper tube, so that a larger cutter advancing amount is usually set in the prior art, the cutter is ensured to have enough cutting amount, and the paper tube is completely cut off. But the inside metal dabber that is of paper tube, the interval between paper tube inner wall and the dabber is very little moreover, and the cutter is after cutting off the paper tube, and the in-process that continues is very easy collide with the dabber, leads to the cutter to roll up the sword, causes the incision in follow-up cutting process unsmooth, influences paper tube quality, causes the scrapping even to need frequently to change the cutter, reduce machining efficiency. Moreover, because cutter and dabber frequently collide, the cutter is with dabber surface fish tail, after a period of time, and dabber surface is scratched the scratch by the cutter, causes dabber surface roughness, leads to the paper tube to be unstable when high-speed rotation easily, also can cause the incision not smooth, influences cutting quality to need to change the dabber, increase processing cost.

Disclosure of Invention

The application provides a novel paper tube cutting machine, which aims at solving the problems that the existing paper tube cutting machine is low in machining efficiency, and the cutter cannot be automatically detected to cause damage due to collision of the cutter and a mandrel, so that the machining efficiency is affected, the maintenance cost is increased, and the like.

The technical scheme adopted by the invention is as follows:

A paper tube cutting machine comprises a frame and a control system, wherein a mandrel fixing device and a driving device are arranged at one end of the frame, and a clamping and rotating device is arranged at the other end of the frame; the central roller is arranged at the central position of the mandrel fixing device, N mandrels are arranged at the edge of the central roller, N is an even number, and every two mandrels form a group of mandrel groups; the machine frame is also provided with a horizontal moving device, and a cutter device is arranged above the horizontal moving device.

As a further improvement of the above technical scheme:

The mandrel fixing device comprises a first fixing disc and a second fixing disc, and the two fixing discs are connected through a connecting sleeve; the edges of the first fixed disc and the second fixed disc are provided with mandrel mounting holes, the mandrel mounting holes are provided with adjusting seats, the side surfaces of the adjusting seats are provided with central adjusting screws, and the adjusting seats are provided with central through holes communicated with the mandrel mounting holes; the mandrel is fixed in the adjusting seat and the mandrel mounting hole.

The edge of the first fixed disc is uniformly distributed with 4 pin shaft holes, and two mandrels are arranged between every two pin shaft holes; the mandrel fixing device further comprises a third air cylinder, and a piston rod of the third air cylinder is connected with a fixing rod.

The diameter of the mandrel is in clearance fit with the aperture of the mandrel mounting hole or slightly smaller than the aperture of the mandrel mounting hole.

The N is 4, 6 or 8; the distance between two mandrels of the same mandrel group is larger than the distance between adjacent mandrels of the two mandrel groups.

The number of the mandrels is 4, and the mandrels are uniformly distributed on the edge of the fixed disc.

The cutter device comprises a second air cylinder, a piston rod of the second air cylinder is connected with a sliding block, the sliding block is arranged on a guide rail, and the guide rail is fixed on the base; an insulating seat is fixed on the sliding block and is provided with an insulating material, a through hole is processed in the insulating material, and a conductive connecting shaft is arranged in the through hole; one end of the connecting shaft is connected with a cutter fixing disc, a cutter is arranged on the cutter fixing disc, and the other end of the connecting shaft is connected with a cutter rotating mechanism; and a signal wire is arranged on the insulating seat, one end of the signal wire is electrically conducted with the connecting shaft, the other end of the signal wire is communicated with the control system, and the cutter is sequentially communicated with the control system through the cutter fixing disc, the connecting shaft and the signal wire.

The insulating seat is provided with a metal conductive bolt, the conductive bolt passes through the insulating material and then contacts with the connecting shaft, and the conductive bolt is externally connected with the signal wire.

The cutter rotating mechanism consists of a stepping motor and a reduction gear, and the reduction gear is made of insulating materials.

The cutter device is provided with an upper set and a lower set, and the two sets of cutter devices are fixed together.

The machine frame is also provided with a bearing hole, one end of the central roller is fixed on the mandrel fixing device, and the other end of the central roller is inserted into the bearing hole and connected with a piston rod of the fourth cylinder.

The clamping and rotating device comprises a chuck and an ejector rod behind the chuck, wherein the chuck is opposite to the free end of the mandrel for cutting; one end of the ejector rod, which is close to the chuck, is provided with a conical ejector rod head, and the other end of the ejector rod is connected with a piston rod of the first cylinder.

The horizontal moving device comprises a second motor, an output shaft of the second motor is connected with a screw rod, connecting seats are arranged at two ends of the screw rod, and the cutter device is arranged on a screw rod nut.

The driving device comprises a third motor, the third motor is connected with a speed reducer, and an output shaft of the speed reducer is connected with the mandrel fixing device.

The beneficial effects of the invention are as follows:

The mandrel fixing device provided by the invention adopts the front fixing disc, the rear fixing disc and the fixing rod, so that the mandrel can be effectively fixed, and the shaking of the mandrel is avoided. Simultaneously the outside of the mandrel is fixed through the adjusting seat, and the axis of the mandrel can be finely adjusted through the central adjusting screw, so that the mandrel can be fixed to avoid shaking, the axis of the mandrel can be adjusted, the axis of the mandrel is ensured to meet the requirement of collimation degree in the processing process, and the processing quality is improved.

The invention has 4 groups of 8 mandrels, each group has own functions, and two cutters are matched, so that the invention is convenient for operators to operate, and can improve the processing efficiency by more than one time compared with the prior art.

According to the cutter device, the cutter is arranged on the insulating seat, when the cutter is in contact with the mandrel to form a current path, current is generated in the whole path, and the control system immediately controls the cutter to retract after detecting a current signal, so that collision between the cutter and the mandrel can be avoided, damage to the cutting edge of the cutter and the surface of the mandrel can be prevented, the service lives of the cutter and the mandrel can be prolonged, the production and processing cost can be reduced, the replacement times can be reduced, and the production efficiency can be greatly improved.

The cutter device is provided with the cutter rotating mechanism, and in the processing process, when the cutting edge at one position of the cutter works for a certain time or cuts a certain number of times, the cutter rotating mechanism drives the cutter to rotate for a certain angle, so that a new cutting edge part aims at a paper tube to cut, the cutting edge at one position is avoided, and the service life of the cutter is prolonged.

Drawings

Fig. 1 is a front view of a paper tube cutter of the present invention.

Fig. 2 is a right side view of the paper tube cutter of the present invention.

Fig. 3 is a top view of the paper tube cutting machine of the present invention, with the clamping and rotating device not shown.

Fig. 4 is a schematic structural view of the clamping and rotating device of the present invention.

Fig. 5 is a schematic structural view of the driving device and the mandrel fixing device according to the present invention.

Fig. 6 is a perspective view of the mandrel and mandrel fixture of the present invention.

Fig. 7 is a right side view of fig. 6.

Fig. 8 is an enlarged view of the mandrel fastening structure of fig. 5.

Figure 9 is a schematic view of the cooperation of the cutter assembly and the mandrel of the present invention.

Figure 10 is a top view of the cutting device of the present invention.

Fig. 11 is a cross-sectional view taken along AA in fig. 10, showing the structure of only one cutter.

Fig. 12 is a cross-sectional view along the BB direction in fig. 10, showing the structure of only one cutter.

In the figure: 1. a frame; 2. clamping and rotating device; 3. a cutter device; 4. a horizontal movement device; 5. a mandrel fixture; 6. a driving device; 7. a control system; 8. a mandrel; 9. a center roller; 10. a mandrel set; 21. a claw; 22. a top head; 23. a push rod; 24. a first cylinder; 25. a first motor; 26. a transmission belt; 27. driven wheel; 28. a bearing hole; 29. a fourth cylinder; 31. a cutter; 32. a second cylinder; 33. a cutter rotating mechanism; 34. an insulating base; 35. a connecting shaft; 36. a conductive bolt; 37. a signal line; 39. a fixing bolt; 40. a base; 41. a cutter fixing plate; 42. a second motor; 43. a screw rod; 44. a connecting seat; 45. a guide rail; 46. a slide block; 51. a first fixed plate; 52. a second fixed disk; 53. connecting sleeves; 54. a pin shaft hole; 55. a third cylinder; 56. a fixed rod; 57. an adjusting seat; 58. a center adjustment screw; 59. a bolt; 61. a third motor; 62. a speed reducer.

Detailed Description

The following describes specific embodiments of the present invention with reference to the drawings.

The overall structure of the paper tube cutting machine of the invention is shown in fig. 1 and 3, and comprises a frame 1 and a control system 7, wherein a mandrel fixing device 5 and a driving device 6 are arranged at one end of the frame 1, a clamping and rotating device 2 is arranged at the other end of the frame, and the driving device 6 is connected with the mandrel fixing device 5 to be fixed for driving the mandrel fixing device 5 to rotate and horizontally move, and can play a role in fixing the position of the mandrel fixing device 5. The central position of the mandrel fixing device 5 is provided with a central roller 9, the edge of the mandrel fixing device is provided with a plurality of mandrels 8, one end of each mandrel 8 is fixedly arranged on the mandrel fixing device 5, and the other end of each mandrel 8 is opposite to the clamping rotating device 2. The machine frame 1 is also provided with a horizontal moving device 4, a cutter device 3 is arranged above the horizontal moving device 4, the horizontal moving device 4 can drive the cutter device 3 to horizontally move, and the cutter device 3 cuts a paper tube sleeved on the mandrel 8 to form a small paper tube with a certain length by moving a certain distance each time.

As shown in fig. 5, the driving device 6 of the present invention includes a third motor 61, the third motor 61 is connected with a decelerator 62, and an output shaft of the decelerator 62 is connected with the outside of the first fixing plate 51 of the spindle fixing device 5. The third motor 61 is used to drive the spindle fixture 5 to rotate precisely, for example, by 90 degrees, after being decelerated by the decelerator 62. As shown in fig. 5 to 8, the mandrel fixing device 5 of the present invention includes a first fixing plate 51 on the left side and a second fixing plate 52 on the right side, and the two fixing plates are connected together by a connecting sleeve 53. The central position of the mandrel fixing device 5 is provided with a central roller 9, and one end of the central roller 9 can be fixed at the central position of the second fixing disc 52 or can pass through the second fixing disc 52 to be fixed by two fixing discs. The edges of the first fixed disc 51 and the second fixed disc 52 are respectively provided with 8 mandrel mounting holes and 4 pin holes 54, the 4 pin holes 54 are uniformly distributed on the edge of the fixed disc at 90 degrees, and two mandrel mounting holes are arranged between every two pin holes 54. An adjusting seat 57 is arranged at the position of each mandrel mounting hole, the adjusting seat 57 is provided with a central through hole, the through holes are communicated with the mandrel mounting holes, and the adjusting seat 57 is fixed on the fixed disc through bolts 59. The mandrel 8 is inserted into the adjusting seat 57 and the mandrel mounting hole, and the mandrel 8 is fixed by a plurality of center adjusting screws 58 on the periphery of the adjusting seat 57. The diameter of the mandrel 8 is in clearance fit with, or slightly smaller than, the aperture of the mandrel mounting hole.

As shown in fig. 5, the mandrel fixing device 5 of the present invention further includes a third cylinder 55, a piston rod of the third cylinder 55 is connected with a fixing rod 56, the diameter of the fixing rod 56 is slightly smaller than the diameter of the pin hole 54, and the third cylinder 55 can push the fixing rod 56 into the pin hole 54 of the first fixing disc 51. When the cutting machine works, the driving device 6 drives the mandrel fixing device 5 to rotate to a position to be cut, the fixing rod 56 is just right opposite to one of the pin shaft holes 54, and the third air cylinder 55 pushes the fixing rod 56 into the pin shaft hole 54, so that the effect of fixing the positions of the mandrel fixing device 5 and the mandrel 8 can be achieved, and abnormal cutting of paper tubes caused by deflection of the mandrel 8 in the cutting process is avoided.

When the paper tube cutting machine carries out cutting processing, the paper tube sleeved on the mandrel 8 needs to rotate at a high speed and is tangent with the cutter to finish cutting, so that the requirement on the collimation degree of the axis of the mandrel 8 is very high, if the axis of the mandrel 8 deviates, the paper tube can shake when rotating at a high speed, the flatness of the paper tube notch and the processing quality of the paper tube are affected, and even the cutter collides with the mandrel 8, so that the mandrel 8 and the cutter are damaged. Therefore, the invention can prevent the mandrel 8 from shaking during the working process of the cutting machine by installing the mandrel 8 through the front and rear fixed discs. Meanwhile, the central adjusting screw 58 can fix the mandrel 8 and the adjusting seat 57 together, and fine adjustment of the axis of the mandrel 8 can be realized by adjusting the distances of different central adjusting screws 58, so that the axis of the mandrel 8 meets the requirement of collimation in the processing process. Furthermore, the fixing plate is positioned by the fixing rod 56, so that the whole mandrel fixing device 5 can be prevented from shaking, and the mandrel 8 is ensured not to deflect in the processing process.

In this embodiment, the number of mandrels 8 is N, where N is an even number, preferably 4 or 6 or 8, and each two mandrels 8 form a mandrel set 10 for simultaneously cutting 2 paper tubes. The cutter device 3 is provided with an upper group of cutters and a lower group of cutters, but because of the limitation of cutter size, the distance between two mandrels 8 of the same mandrel group 10 is larger than the distance between adjacent mandrels 8 of the two mandrel groups 10 in order to facilitate the installation of the cutter device 3.

Referring to fig. 9, when the paper tube cutting machine works, 8 mandrels form 4 groups of mandrel groups 10, which respectively have different functions, two mandrels 8 vertically arranged on the right side form one group of mandrel groups 10, each mandrel 8 is sleeved with a paper tube, the cutter device 3 is provided with an upper cutter and a lower cutter, and can cut the two paper tubes at the same time, so that the processing efficiency is doubled compared with that of cutting a single paper tube in the prior art. The top mandrel set 10 has been fitted with two paper tubes to be cut. The left mandrel set 10 faces the operator, who removes the previously cut small paper tube and performs a preliminary inspection while sleeving a new long paper tube on the mandrel 8, when the cutter cuts the right paper tube. While the lowest mandrel set 10 has two mandrels 8 that are sleeved with cut small paper tubes, but because the two mandrels are located lowest, the operation is inconvenient and the two mandrels serve as transition zones. When the two paper tubes on the right side are cut, the control system 7 of the cutting machine controls the third motor 61 to work, and after the speed is reduced by the speed reducer 62, the mandrel fixing device 5 is driven to precisely rotate by 90 degrees, at the moment, the mandrel group 10 on the top rotates to the right side to carry out the next group of cutting, and meanwhile, the other 3 groups of mandrel groups 10 also rotate to the next working procedure.

The invention preferably adopts 4 groups of 8 mandrels, each group has own functions, so that the operation of an operator can be facilitated, and the processing efficiency can be improved by more than one time by matching with the cutter device 3 with two groups of cutters.

Of course, the invention can also adopt 4 mandrels, the 4 mandrels are uniformly distributed at the edge of the fixed disk, the functions of the 4 mandrels are the same as the functions of the 4 mandrel groups 10, but compared with 8 mandrels, the cutting efficiency is twice as low.

Of course, the number of mandrels may be set to N, where N is an even number and n+.4, and each two mandrels 8 may form a set of mandrels 10, for example, only a left side up-down mandrel set 10 and a right side cutting mandrel set 10.

As shown in fig. 3, the horizontal moving device 4 of the present invention includes a second motor 42, an output shaft of the second motor 42 is connected with a screw rod 43, two ends of the screw rod 43 are provided with connecting seats 44, and the cutter device 3 is mounted on a screw rod nut. When the second motor 42 works, the cutter device 3 is driven to horizontally move through the screw rod 43. The length of the paper tube product is set in the cutter control system 7, after the cutter device 3 completes one-time cutting, the horizontal moving device 4 drives the cutter device 3 to horizontally move by the same distance as the length of the paper tube product, next cutting is carried out, and the whole long paper tube is cut in sequence. When the whole long paper tube is cut, the horizontal moving device 4 drives the cutter device 3 to return to the starting position, and the next long paper tube is ready to be cut.

As shown in fig. 9, the cutter device 3 of the present invention includes two sets of cutters, an upper set and a lower set, which are fixed together. Taking the above cutter as an example, as shown in fig. 10, 11 and 12, the cutter device 3 includes a second cylinder 32, a piston rod of the second cylinder 32 is connected with a slider 46, the slider 46 is mounted on a guide rail 45, and the guide rail 45 is fixed on the base 40. An insulating seat 34 is arranged above the sliding block 46 through a fixing bolt 39, and the insulating seat 34 is made of insulating materials. The insulating base 34 is provided with a central through hole perpendicular to the axis of the second cylinder 32 in a horizontal direction, a connecting shaft 35 is installed in the hole, the connecting shaft 35 can conduct electricity, one end of the connecting shaft 35 is provided with a cutter rotating mechanism 33, the other end of the connecting shaft is connected with a cutter fixing disc 41, and the cutter fixing disc 41 is provided with a cutter 31. In this embodiment, the cutter rotating mechanism 33 is composed of a stepping motor and a reduction gear, the reduction gear is made of an insulating material, the connection shaft 35 is electrically isolated from the stepping motor, and the cutter rotating mechanism 33 is used for driving the connection shaft 35 and the cutter 31 to rotate by a certain angle. A metal conductive bolt 36 is arranged above the insulating seat 34, the conductive bolt 36 passes through the upper half part of the insulating seat 34 and is contacted with the connecting shaft 35, meanwhile, a signal wire 37 is externally connected with the conductive bolt 36, the signal wire 37 is connected with the control system 7, and the control system 7 controls and applies a safe voltage. With the above structure, the signal line 37 is connected to the cutter 31 through the conductive bolt 36, the connection shaft 35, and the cutter fixing plate 41 in this order.

When the cutter device 3 starts to work, the cutter 31 is not in contact with the paper tube, and at this time, the voltage is applied to the cutter 31, but no current passes through the cutter. The second cylinder 32 pushes the slide 46 and the cutter 31 to move to the position of the mandrel 8, and the second cylinder is tangent to the paper tube rotating at a high speed, so that the paper tube is cut off. After the paper tube is cut, the cutter 31 continues to move forward, and when the cutter 31 contacts the mandrel 8, a passage is formed through the entire cutter since the mandrel 8 is a metal material. Therefore, when the cutter 31 is in contact with the mandrel 8, a current path is formed, and a current is generated in the entire path, and at this time, a current also flows in the signal line 37, and after the control system 7 detects the current signal of the signal line 37, the control system immediately controls the second cylinder 32 to retract, so that the cutter 31 is retracted to the initial position. Through the cooperation of above different insulation and conductive structure, control system 7 can just monitor the electric current in the moment that cutter 31 contacted with dabber 8, and control cutter 31 returns, and cutter 31 can not collide with dabber 8, avoids damaging the cutting edge of cutter 31 and dabber 8's surface, improves cutter 31 and dabber 8's life, reduces production processing cost to can reduce the change number of times, improve production efficiency greatly.

In the process of cutting the paper tube, since the cutter 31 does not need to rotate at a high speed, if the cutter 31 is always used for cutting at one position, the cutting edge of the cutter 31 is curled, and the quality of the cut of the paper tube is affected. According to the invention, the cutter rotating mechanism 33 is arranged, when the cutting edge at one position of the cutter 31 works for a certain time or cuts a certain number of times, the cutter rotating mechanism 33 drives the cutter 31 to rotate for a certain angle, so that a new cutting edge part aims at the paper tube to cut, the cutting edge at one position is avoided, and the service life of the cutter 31 is prolonged.

As shown in fig. 4, the clamping and rotating device 2 of the present invention is used for clamping a paper tube and driving the paper tube to rotate at a high speed, and comprises two chucks and a push rod 23 behind the chucks, wherein the two chucks are opposite to the free ends of two mandrels 8 for cutting, each chuck is provided with at least two jaws 21, the number of the jaws is preferably three or four, one end of the push rod 23, which is close to the chucks, is provided with a conical push rod head 22, the other end of the push rod 23 is connected with a piston rod of a first cylinder 24, and the first cylinder 24 can push the push rod 23 to horizontally move so as to jack up the jaws 21 and release the clamped paper tube.

As shown in fig. 2, the clamping and rotating device 2 of the present invention further includes a first motor 25, the first motor 25 is connected to two driven wheels 27 through a transmission belt 26 or a gearbox, the driven wheels 27 are connected to a chuck, and a connection structure between the driven wheels 27 and the chuck is a conventional technology, which is not specifically explained in the present invention. In operation, the first motor 25 drives the chuck and the paper tube clamped by the chuck to rotate at a high speed through the driven wheel 27, and the cutting process is completed. The frame 1 beside the driven wheel 27 is also provided with a bearing hole 28, one end of the central roller 9 is fixed on the mandrel fixing device 5, and the other end is inserted into the bearing hole 28 and connected with a piston rod of a fourth cylinder 29. Through the positioning of the mandrel fixing device 5 and the bearing hole 28, the central axis of the central roller 9 in the cutting machine can be ensured to be stable, the axis of the mandrel 8 on the mandrel fixing device 5 is ensured not to deviate, and the cutting quality is improved. After the paper tube is cut, the claw 21 loosens the paper tube, the fourth cylinder 29 pushes the center roller 9 and the mandrel fixing device 5 to horizontally move in a direction away from the chuck, the free end of the mandrel 8 and the paper tube leave the chuck, then the mandrel fixing device 5 rotates 90 degrees, the next group of mandrels 8 enter a cutting station, the fourth cylinder 29 pulls the center roller 9 and the mandrel fixing device 5, the free end of the mandrel 8 and the paper tube enter a clamping position of the chuck, and the claw 21 clamps the paper tube to perform the next cutting.

The above description is illustrative of the invention and is not intended to be limiting, and the invention may be modified in any form without departing from the spirit of the invention.

Claims (13)

1. A paper tube cutting machine, characterized in that: comprises a frame (1) and a control system (7), wherein one end of the frame (1) is provided with a mandrel fixing device (5) and a driving device (6), and the other end is provided with a clamping rotating device (2); the central roller (9) is arranged at the central position of the mandrel fixing device (5), N mandrels (8) are arranged at the edge of the central roller, N is an even number, and every two mandrels (8) form a group of mandrel groups (10); a horizontal moving device (4) is also arranged on the frame (1), and a cutter device (3) is arranged above the horizontal moving device (4); the mandrel fixing device (5) comprises a first fixing disc (51) and a second fixing disc (52), and the two fixing discs are connected through a connecting sleeve (53); the edges of the first fixed disc (51) and the second fixed disc (52) are provided with mandrel mounting holes, the mandrel mounting holes are provided with adjusting seats (57), the side surfaces of the adjusting seats (57) are provided with center adjusting screws (58), and the adjusting seats (57) are provided with center through holes communicated with the mandrel mounting holes; the mandrel (8) is fixed in the adjusting seat (57) and the mandrel mounting hole; the machine frame (1) is also provided with a bearing hole (28), one end of the central roller (9) is fixed on the mandrel fixing device (5), and the other end of the central roller is inserted into the bearing hole (28).

2. The paper tube cutting machine of claim 1, wherein: 4 pin shaft holes (54) are uniformly distributed on the edge of the first fixed disc (51), and two mandrels (8) are arranged between every two pin shaft holes (54); the mandrel fixing device (5) further comprises a third air cylinder (55), and a piston rod of the third air cylinder (55) is connected with a fixing rod (56).

3. The paper tube cutting machine of claim 2, wherein: the diameter of the mandrel (8) is in clearance fit with the aperture of the mandrel mounting hole or slightly smaller than the aperture of the mandrel mounting hole.

4. The paper tube cutting machine of claim 1, wherein: the N is 4, 6 or 8; the distance between two mandrels (8) of the same mandrel group (10) is greater than the distance between adjacent mandrels (8) of the two mandrel groups (10).

5. The paper tube cutting machine of claim 1, wherein: the number of the mandrels (8) is 4, and the mandrels are uniformly distributed on the edge of the fixed disc.

6. The paper tube cutting machine of claim 1, wherein: the cutter device (3) comprises a second air cylinder (32), a piston rod of the second air cylinder (32) is connected with a sliding block (46), the sliding block (46) is arranged on a guide rail (45), and the guide rail (45) is fixed on the base (40); an insulating seat (34) is fixed on the sliding block (46), the insulating seat (34) is provided with an insulating material, a through hole is processed in the insulating material, and a conductive connecting shaft (35) is arranged in the through hole; one end of the connecting shaft (35) is connected with a cutter fixing disc (41), a cutter (31) is arranged on the cutter fixing disc (41), and the other end of the connecting shaft (35) is connected with a cutter rotating mechanism (33); the insulating seat (34) is provided with a signal wire (37), one end of the signal wire (37) is electrically communicated with the connecting shaft (35), the other end of the signal wire is communicated with the control system (7), and the cutter (31) is communicated with the control system (7) through the cutter fixing disc (41), the connecting shaft (35) and the signal wire (37) in sequence.

7. The paper tube cutting machine of claim 6, wherein: the insulating seat (34) is provided with a metal conductive bolt (36), the conductive bolt (36) passes through the insulating material and then contacts with the connecting shaft (35), and the conductive bolt (36) is externally connected with the signal wire (37).

8. The paper tube cutting machine of claim 7, wherein: the cutter rotating mechanism (33) consists of a stepping motor and a reduction gear, and the reduction gear is made of insulating materials.

9. The paper tube cutting machine of claim 7, wherein: the cutter device is provided with an upper set and a lower set, and the two sets of cutter devices are fixed together.

10. The paper tube cutting machine of claim 1, wherein: the other end of the center roller (9) is connected with a piston rod of a fourth cylinder (29).

11. The paper tube cutting machine of claim 1, wherein: the clamping and rotating device (2) comprises a chuck and a push rod (23) behind the chuck, wherein the chuck is opposite to the free end of the mandrel (8) for cutting; one end of the ejector rod (23) close to the chuck is provided with a conical ejector rod head (22), and the other end of the ejector rod is connected with a piston rod of a first cylinder (24).

12. The paper tube cutting machine of claim 1, wherein: the horizontal moving device (4) comprises a second motor (42), an output shaft of the second motor (42) is connected with a screw rod (43), connecting seats (44) are arranged at two ends of the screw rod (43), and the cutter device (3) is arranged on a screw rod nut.

13. The paper tube cutting machine of claim 1, wherein: the driving device (6) comprises a third motor (61), the third motor (61) is connected with a speed reducer (62), and an output shaft of the speed reducer (62) is connected with the mandrel fixing device (5).