CN112845986A

CN112845986A - Building engineering reinforcing bar processingequipment

Info

Publication number: CN112845986A
Application number: CN202110012069.6A
Authority: CN
Inventors: 吴跃
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-01-06
Filing date: 2021-01-06
Publication date: 2021-05-28

Abstract

This scheme belongs to the reinforcing bar processing field, concretely relates to building engineering reinforcing bar processingequipment, including shell and motor, motor fixed connection is in the shell, fixedly connected with backup pad in the shell, fixedly connected with dead lever and first cylinder in the shell, the dead lever rotates and is connected with the axis of rotation, coaxial fixedly connected with cutting knife and half side gear in the axis of rotation, first cylinder includes piston and piston rod, first cylinder internal fixation is equipped with the spring, the spring both ends respectively with piston and first cylinder wall fixed connection, the first rack of piston rod fixedly connected with, first rack and half side gear engagement, the fixed water storage tank that is equipped with in shell bottom, the fixed collecting box that is equipped with open-top in water storage tank top. When the cutting knife cuts, the circulating water can be continuously and circularly washed and cooled for the cutting knife, the reinforcing steel bars and the like. When the cutting knife stops cutting, the spray head also stops spraying water outwards, and synchronous automatic control is realized.

Description

Building engineering reinforcing bar processingequipment

Technical Field

This scheme belongs to the reinforcing bar processing field, concretely relates to building engineering reinforcing bar processingequipment.

Background

Reinforcing steel bars (rebars) are steel materials for reinforced concrete and prestressed reinforced concrete, and have a circular cross section, and sometimes a square cross section with rounded corners. Comprises plain round steel bars, ribbed steel bars and twisted steel bars. At the in-process of reinforcing bar processing, the cutting knife lasts and cuts the reinforcing bar, can cause reinforcing bar incision department and cutting knife to generate heat, and the overheated regularity that can influence cutting accuracy and reinforcing bar incision department of temperature leads to the fact certain influence to subsequent use of reinforcing bar. The reinforcing steel bar can carry a lot of earth chips and the like, and the cutting knife can be damaged, so that the processing precision is influenced.

The prior Chinese utility model with the application number of CN201922349161.2 discloses a reinforced concrete drain pipe reinforcing steel bar processing device, which comprises a shell; the motor is fixed at the top of the shell; the cutting assembly is arranged on one side of the motor; the limiting assembly is fixed on one side of the inner wall of the shell; the limiting assembly comprises a supporting plate, and the top of the supporting plate is fixedly connected with a limiting block; the mounting assembly is fixed at the bottom of the supporting plate; a filter assembly disposed on the mounting assembly; the circulating assembly is fixed at the bottom of the inner wall of the shell; a fixed component disposed on the housing. The reinforced concrete drain pipe reinforcing steel bar processing equipment provided by the invention has the advantages that water is sprayed to the cutting position through the two spray heads, the reinforcing steel bar is cooled, and the reinforcing steel bar is prevented from being overheated and oxidized to influence the strength of the reinforcing steel bar. However, the above scheme requires a pump to pressurize the cooling water, wastes electricity and increases the installation cost of the processing apparatus. The cooling water is when cooling for the reinforcing bar, and the temperature of water also can rise, and above-mentioned scheme is simple the cooling water reuse who heaies up the back can not be fine for the reinforcing bar cooling of cutting always.

Disclosure of Invention

This scheme provides a building engineering reinforcing bar processingequipment to solve cooling water automatic cycle, energy-conservation and for the problem of cooling water cooling.

In order to achieve the above purpose, the present scheme provides a building engineering steel bar processing device, which comprises a shell and a motor, wherein the motor is fixedly connected in the shell, a support plate is fixedly connected in the shell, a fixed rod and a first cylinder are fixedly connected in the shell, a one-way air inlet valve is arranged in the first cylinder, the fixed rod is rotatably connected with a rotating shaft, a cutting knife and a half gear are coaxially and fixedly connected on the rotating shaft, the first cylinder comprises a piston and a piston rod, the piston and the piston rod are fixedly connected, a spring is fixedly arranged in the first cylinder, two ends of the spring are respectively fixedly connected with the piston and a first cylinder wall, a first rack is fixedly connected with the piston rod, the first rack is meshed with the half gear, a water storage tank is fixedly arranged at the bottom of the shell, a collecting box with an opening at the top, the bottom surface of the collecting box is an inclined plane with a high side face and a low middle part, the collecting box is communicated with one end of a water pipe, the other end of the water pipe is communicated with the water storage tank, the other end of the water pipe is narrower, a one-way valve from the collecting box to the water storage tank is arranged in the water pipe, the first air cylinder is communicated with one end of the air pipe, the other end of the air pipe is communicated with the water storage tank, the one-way valve from the first air cylinder to the water storage tank is arranged in the air pipe, the water storage tank is communicated with one end of a water spraying pipe, the other end.

The principle of the scheme is as follows: the motor drives the rotating shaft to rotate, and the cutting knife and the half-side gear which are coaxially and fixedly connected with the rotating shaft also rotate along with the rotating shaft. The cutting knife rotates and can cut the reinforcing bar, and half side gear rotates and drives first rack and removes, and first rack promotes the piston rod and applys pressure to the piston, and the piston is at inclosed first cylinder compressed gas. Compressed gas enters into the water storage tank through the air pipe, and in the continuous air inlet process, water in the water storage tank is pressed to the spray head through the spray pipe, and the cutting knife and the reinforcing steel bar which are cutting are cooled. Shower nozzle spun water flows into to top open-ended collection box after for cutting knife and reinforcing bar cooling, and the bottom surface side of collecting box is high, the centre is low, can accelerate the velocity of flow of water, and the one end of water pipe and water storage tank intercommunication is narrower. Therefore, when water flows into the water pipe from the collecting tank and then enters the water storage tank, the flow rate of the water is increased, and the temperature is reduced. Water flows out of the water storage tank and finally flows into the water storage tank, so that the cooling and the recycling of the water are realized. And the water can clean and cool down for cutting knife and reinforcing bar. The half side gear is a half side toothed gear, the first rack can be intermittently moved in the rotating process, after the piston is pushed to the bottom, the non-toothed end of the gear is not in contact with the first rack at the moment, the first rack cannot be pushed to move, the piston rebounds, then the first rack is pushed by the toothed end of the half side first rack again, the piston is compressed again, and the cycle is repeated.

The scheme has the beneficial effects that: 1. for pressurizeing in the water storage tank under the effect of axis of rotation, half side gear, first rack and first cylinder etc. make the water of cutting knife in the in-process water storage tank can cool down and clean for cutting knife and reinforcing bar automatically simultaneously, save electric power, reduce cost, green. When the cutting knife does not rotate for cutting, the water in the water storage tank is also in a static state.

2. The bottom surface side of collecting box is high, the centre is low, and the one end that the water pipe is connected with the water storage tank is narrower, makes the water speed of getting into the water storage tank from the collecting box faster, can cool down for water to improve the cooling effect of circulating water pair cutting knife and reinforcing bar.

3. The water of cleaning and cooling can cyclic utilization, saves cost green.

4. The water can carry the cut debris into a collection tank below. Preventing the debris from splashing.

Furthermore, a filter screen is fixedly arranged in the collecting box. The filter screen in the collecting box can be to steel fillings and rubbish etc. the interception that drop in the collecting box on the filter screen, and only water can flow below the filter screen, keeps the cleanness of circulating water.

Further, the number of the springs is more than 1. The spring can increase the speed that the piston kick-backed, and the distance that the piston rebounded in the short time is big more, and the distance that the piston can be compressed next time is also big more, and is more to the gas of bin input, and the water pressure of production is big more, and the effect of cleanness and cooling is better.

Furthermore, a check valve is arranged on the water spraying pipe. After water enters the spray pipe from the storage tank, because water moves from bottom to top, the required pressure ratio is larger, the check valve is installed to prevent the backflow of water which is pressed upwards, the water supply pressure in the water storage tank is reduced, the water flow at the spray head is larger, and the cleaning and cooling effects are better.

Further, shell internal fixation is equipped with second cylinder and liquid nitrogen container, be equipped with the liquid nitrogen in the liquid nitrogen container, the second cylinder internal fixation is equipped with one-way admission valve, piston rod fixedly connected with second rack in the second cylinder, second rack and half side gear engagement, second cylinder and liquid nitrogen container intercommunication, be equipped with the check valve from second cylinder to liquid nitrogen container between second cylinder and the liquid nitrogen container, liquid nitrogen container fixedly connected with denitrogenation pipe, be connected with first sheetmetal one end and second sheetmetal one end in the denitrogenation pipe respectively, first sheetmetal other end and second sheetmetal other end swing joint, two spring one ends of fixedly connected with in the denitrogenation pipe, two spring other ends respectively with first sheetmetal and second sheetmetal fixed connection. When the processing device does not work, the first spring piece is in contact with the second spring piece, the elastic force of the spring is larger than the gravity of liquid nitrogen, and the liquid nitrogen cannot leak out from the middle of the first spring piece and the second spring piece under the support of the elastic force of the spring. When the cutting is carried out, the half-side gear rotates to drive the second rack to move, the second rack drives the piston rod in the second cylinder to move, the piston rod drives the piston to compress gas, the gas flows into the liquid nitrogen tank, the pressure in the liquid nitrogen tank is increasingly higher, the pressure and the gravity of the liquid nitrogen per se are greater than the elastic force of the first spring piece and the second spring piece connecting spring, the contact positions of the first spring piece and the second spring piece are separated, and the liquid nitrogen is discharged from the middle of the first spring piece and the second spring piece. After the liquid nitrogen is discharged, the pressure in the liquid nitrogen tank is reduced, the first spring piece and the second spring piece are restored to the closed state, and the liquid nitrogen does not leak. The liquid nitrogen has low temperature and good cooling effect, but the storage requirement of the liquid nitrogen is also high, so a metal liquid nitrogen tank specially used for storage is needed. Because the boiling point of liquid nitrogen is lower, can vaporize at once after liquid nitrogen discharges the liquid nitrogen container under the normal atmospheric temperature, because the temperature of liquid nitrogen is lower, the vaporization also can absorb the heat, so can play fine cooling effect to the reinforcing bar of cutting and cutting knife. The one-way valve between the second cylinder and the liquid nitrogen tank can prevent liquid nitrogen in the liquid nitrogen tank from flowing to the second cylinder.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is a schematic structural diagram of a cutting knife according to an embodiment of the present invention.

FIG. 3 is a schematic structural view of a nitrogen discharging pipe according to an embodiment of the present invention.

Detailed Description

The following is further detailed by the specific embodiments:

reference numerals in the drawings of the specification include: the device comprises a shell 1, a motor 2, a water storage tank 3, a water spray pipe 4, an air pipe 5, a fixing rod 6, a half-side gear 7, a supporting plate 8, a collecting box 9, a filter screen 10, a first rack 11, a first air cylinder 12, a spray head 13, a water pipe 14, a check valve 15, a check valve 16, a rotating shaft 17, a second rack 18, a second air cylinder 19, a liquid nitrogen tank 20, a nitrogen discharge pipe 21, a first metal sheet 22, a second metal sheet 23 and a cutting knife 24.

The embodiment is substantially as shown in figures 1 and 2:

the shell 1 is a metal shell of the whole reinforcing steel bar processing device, and the middle of the shell is hollow.

The motor 2 provides power for the rotating shaft 17 to enable the rotating shaft 17 to rotate, and the motor 2 is fixedly connected in the shell 1.

The water storage tank 3 is a closed non-metal tank body, is communicated with the collecting tank 9 through a water pipe 14, is communicated with the first air cylinder 12 through an air pipe 5, is communicated with the spray nozzle 13 through a spray pipe 4, and provides circulating water with certain pressure for the spray nozzle 13.

The spray pipe 4 is a hard non-metal pipe and is fixedly connected in the shell 1, one end of the spray pipe is communicated with the water storage tank 3, and the other end of the spray pipe is fixedly connected with the spray head 13.

The trachea 5 is the tubular metal resonator, and one end and first cylinder 12 intercommunication, one end and water storage tank 3 intercommunication, compressed gas in the first cylinder 12 advances the picture to the water storage tank 3 in through trachea 5, discharges the water in the water storage tank 3.

The fixed rod 6 is a metal rod, one end of the fixed rod is fixedly connected to the top surface of the shell 1, and the other end of the fixed rod is rotatably connected with a rotating shaft 17.

The half gear 7 is coaxially and fixedly connected with the rotating shaft 17. The half gear 7 is a half toothed gear, and since the piston in the first cylinder 12 is to be reset after being compressed, the compression can be performed again, and the half gear 7 can achieve a corresponding effect when rotating. Compression is performed when the toothed side is engaged with the first rack 11, and the piston is rebounded and then compressed again when the non-toothed side passes the first rack 11 side.

The support plate 8 is fixedly connected to the inner wall of the housing 1, and can bear processed or unprocessed steel, and also can prevent a part of chips and garbage from falling below.

The collecting box 9 is a non-metal box body with an opening at the upper part, and a filter screen 10 is fixedly arranged inside the non-metal box body. The collection box 9 can collect water, metal chips, garbage, and the like falling from above. The bottom surface of the collecting box 9 is an inclined plane with two sides higher than the middle part lower than the middle part, so that water can quickly flow into the water pipe 14 from the box body, the water flow speed is increased, and the water temperature is reduced.

The filter screen 10 is a metal filter screen with small meshes, so that metal chips, garbage and other objects can be left on the filter screen, and water flows down from the filter screen to play a role in cleaning water.

The first rack 11 is a metal first rack, and one end of the first rack is fixedly connected with a piston rod of the first cylinder 12. The first rack 11 is engaged with the half gear 7, and the first rack 11 can horizontally slide in the housing 1.

The first cylinder 12 is hermetically sealed and fixedly disposed within the housing 1. The first cylinder 12 is composed of a piston rod and a piston, one end of the piston rod is fixedly connected with the piston, and the piston rod slides in the first cylinder 12 along with the piston. The piston is fixedly connected to one end of a spring, the other end of which is fixedly connected to the bottom inside the first cylinder 12. The first cylinder 12 is provided with a one-way air inlet valve, and after the compression of the piston is finished, air enters the first cylinder from the air inlet valve for the next compression.

Shower nozzle 13 is metal nozzle, and fixed connection is in the one end of spray pipe 4, and the water in the spray pipe 4 is through 13 blowout of shower nozzle, washs and cools down for cutting knife and reinforcing bar etc..

The water pipe 14 is a nonmetal pipe and is communicated with the collecting box 9 and the water storage tank 3, the lower end of the water pipe 14 is narrow, the flow speed of water flowing into the water pipe 14 from the collecting box 9 is accelerated, and the temperature of the water can be further reduced.

The check valve 15 is the metal valve, and fixed the setting is in the upper end of spray pipe 4, and after water was impressed the spray pipe 4 from water storage tank 3, the high than higher of spray pipe 4, needs great pressure, and the check valve can prevent to have been pressed the water backward flow, alleviates the pressure that water storage tank 3 supplied water, improves the water yield and the washing cooling effect of shower nozzle water spray.

The check valves 16 are fixedly arranged in the air pipe 5 and the water pipe 14 respectively, and are a check valve from the first air cylinder 12 to the water storage tank 3 and a check valve from the collecting tank 9 to the water storage tank 3 respectively. All function to prevent gas from escaping, resulting in a reduction of pressure within the water storage tank 3.

The rotating shaft 17 is a metal shaft and is rotatably connected to the fixing rod 6. The rotating shaft 17 is coaxially and fixedly connected with a half gear 7 and a cutting knife 24. The rotating shaft 17 can drive the half gear 7 and the cutting knife 24 to rotate.

The second rack 18 is a metal rack and is engaged with the half gear 7. One end of the second rack 18 is fixedly connected with one end of a piston rod of the second cylinder 19. The second rack 18 slides horizontally in the housing 1 and can drive the piston rod of the second cylinder 19 to move.

The second cylinder 19 is fixedly arranged in the housing 1 and comprises a piston rod and a piston. A spring is arranged in the second cylinder 19, and two ends of the spring are respectively fixedly connected with the piston and the bottom of the cylinder body. A one-way air inlet valve is fixedly arranged in the second air cylinder 19, and only air can be fed into the air cylinder but not discharged. The second cylinder 19 is communicated with a liquid nitrogen tank 20, and a check valve from the second cylinder 19 to the liquid nitrogen tank 20 is arranged between the second cylinder 19 and the liquid nitrogen tank 20 to prevent liquid nitrogen in the liquid nitrogen tank 20 from flowing back to the second cylinder 19.

The cutting knife 24 is made of metal and is coaxially and fixedly connected to the rotating shaft 17.

As shown in fig. 3:

the liquid nitrogen tank 20 is a metal closed container in which liquid nitrogen is stored, and can withstand low temperature and high pressure. The liquid nitrogen tank 20 is fixedly arranged in the shell 1. The liquid nitrogen tank 20 is fixedly connected and communicated with a nitrogen discharge pipe 21.

The nitrogen discharging pipe 21 is a metal pipe and can withstand low temperature. Two sides in the nitrogen discharging pipe 21 are fixedly connected with one ends of two springs respectively, and the other ends of the two springs are fixedly connected with the first metal sheet 22 and the second metal sheet 23 respectively. Under the interaction of the gravity of the liquid nitrogen and the elastic force of the spring, the first metal sheet 22 and the second metal sheet 23 are in a closed equilibrium state, and the liquid nitrogen cannot flow out from the middle of the first metal sheet 22 and the second metal sheet 23. When the second cylinder 19 compresses gas into the liquid nitrogen tank 20, the gravity borne by the first metal sheet 22 and the second metal sheet 23 is larger than the elastic force of the spring, and a part of liquid nitrogen is discharged from the space between the first metal sheet 22 and the second metal sheet 23 to cool the cutting knife 24 and the steel bar.

The first metal sheet 22 and the second metal sheet 23 are corrosion-resistant, low-temperature-resistant metal thin sheets.

In the specific operation:

the motor 2 is turned on, the rotating shaft 17 starts to rotate and drives the half gear 7 and the cutting blade 24 to rotate. The cutting knife 24 cuts the reinforcing steel bars to be processed. Meanwhile, the half-side gear 7 drives the first rack 11 to move towards the first cylinder 12, the first rack 11 drives the piston rod fixedly connected with the first rack to move, and the piston rod presses the piston to slide in the first cylinder 12. The compressed gas of the piston enters the gas pipe 5, and the compressed gas enters the water storage tank 3 through the gas pipe 5. The air pipe 5 is provided with a check valve 16 from the first cylinder 12 to the water storage tank 3, so that the air does not flow back. A one-way valve 16 is also provided in the water pipe 14 from the collection tank 9 to the water storage tank 3 so that gas does not escape from the water pipe 14. The water storage tank 3 is closed, and under the condition that the air pressure in the tank is continuously increased, water in the water storage tank 3 is discharged from the water spraying pipe 4, and the cutting knife 24 and the reinforcing steel bars which generate heat are cooled and cleaned through the spray head 13. The check valve 15 prevents water that has been pressed into the spout 4 from flowing back into the water storage tank 3. After the cutting knife 24 and the steel bars are washed and cooled, water and impurities fall into the collecting tank 9 together, the impurities are filtered by the filter screen 10 and are left above the filter screen 10, and the water flows into the water storage tank 3 from the collecting tank 9 through the water pipe 14. The bottom surface of the collecting box 9 is an inclined plane with high side surface and low middle part, which can accelerate the flow rate of water, and can accelerate the flow rate of water when flowing through the water pipe 14 with narrow lower end, the flow rate of water accelerates the temperature of water, and the cooling effect of circulating water is improved. After the water returns to the water storage tank 3, the temperature is reduced, impurities are removed, the water passes through the spray pipe 4 to the spray head 13 again, the cutting knife 24, the reinforcing steel bars and the like are washed and cooled, and the circulation is repeated.

When the cutting knife 24 is used for cutting, circulating water can continuously and circularly wash and cool the cutting knife 24, the reinforcing steel bars and the like. When the cutting knife 24 stops cutting, the spray head 13 also stops spraying water outwards, and synchronous automatic control is realized.

When the half gear 7 rotates, the second rack 18 is driven by the half gear 7, the second rack 18 drives the piston rod in the second cylinder 19 to move, the piston in the second cylinder 19 moves under the driving of the piston rod, the second cylinder 19 is closed, and the piston compresses the gas in the second cylinder 19 to enter the liquid nitrogen tank 20. After compression is complete, the spring in the second cylinder 19 resets the piston and air enters through the one-way inlet valve. The pressure in the liquid nitrogen tank 20 increases and the weight force borne above the first metal sheet 22 and the second metal sheet 23 increases. The first and

second metal sheets

22 and 23 are closed, and the weight force borne by the upper side and the elastic force of the spring are balanced. When the gravity borne by the first metal sheet 22 and the second metal sheet 23 is larger than the elastic force of the spring, a part of liquid nitrogen is discharged from between the first metal sheet 22 and the second metal sheet 23, and the temperature of the cutting knife 24 and the steel bar is reduced. After a part of liquid nitrogen and air are discharged, the pressure in the liquid nitrogen tank 20 is reduced, the bearing gravity above the first metal sheet 22 and the second metal sheet 23 is reduced, the bearing gravity is balanced with the elastic force of the spring again, the first metal sheet 22 and the second metal sheet 23 are closed, and the liquid nitrogen and the air can not leak.

The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. The utility model provides a building engineering reinforcing bar processingequipment, includes shell (1) and motor (2), motor (2) fixed connection is in shell (1), fixedly connected with backup pad (8), its characterized in that in shell (1): the improved air conditioner is characterized in that a fixing rod (6) and a first air cylinder (12) are fixedly connected in the shell (1), a one-way air inlet valve is arranged in the first air cylinder (12), the fixing rod (6) is rotatably connected with a rotating shaft (17), a cutting knife (18) and a half gear (7) are fixedly connected on the rotating shaft (17) in a coaxial mode, the first air cylinder (12) comprises a piston and a piston rod, the piston and the piston rod are fixedly connected, a spring is fixedly arranged in the first air cylinder (12), two ends of the spring are fixedly connected with the piston and the wall of the first air cylinder respectively, a first rack (11) is fixedly connected with the piston rod, the first rack (11) is meshed with the half gear (7), a water storage tank (3) is fixedly arranged at the bottom of the shell (1), a collecting box (9) with an opening at the top is fixedly arranged above the water storage tank (3), and the, The middle low inclined plane, collecting box (9) intercommunication has water pipe (14) one end, water pipe (14) other end and water storage tank (3) intercommunication and water pipe (14) other end are narrower, be equipped with the check valve from collecting box (9) to water storage tank (3) in water pipe (14), first cylinder (12) intercommunication has trachea (5) one end, trachea (5) other end and water storage tank (3) intercommunication, be equipped with check valve (16) from first cylinder (12) to water storage tank (3) in trachea (5), water storage tank (3) intercommunication has spray pipe (4) one end, spray pipe (4) other end fixedly connected with shower nozzle (13), shower nozzle (13) cooperate with cutting knife (18).

2. The constructional engineering steel bar processing device as claimed in claim 1, wherein: a filter screen (10) is fixedly arranged in the collection box (9).

3. The constructional engineering steel bar processing device as claimed in claim 1, wherein: the number of the springs is more than 1.

4. The constructional engineering steel bar processing device as claimed in claim 1, wherein: and a check valve (15) is arranged on the water spraying pipe (13).

5. The constructional engineering steel bar processing device as claimed in claim 1, wherein: the shell (1) is internally fixed with a second cylinder (19) and a liquid nitrogen tank (20), liquid nitrogen is arranged in the liquid nitrogen tank (20), the second cylinder (19) is internally fixed with a one-way air inlet valve, a piston rod fixedly connected with second rack (18) in the second cylinder (19), the second rack (18) is meshed with a half-side gear (7), the second cylinder (19) is communicated with the liquid nitrogen tank (20), a one-way valve from the second cylinder (19) to the liquid nitrogen tank (20) is arranged between the second cylinder (19) and the liquid nitrogen tank (20), the liquid nitrogen tank (20) is fixedly connected with a nitrogen discharge pipe (21), one end of a first metal sheet (22) and one end of a second metal sheet (23) are respectively connected in the nitrogen discharge pipe (21), the other end of the first metal sheet (22) is movably connected with the other end of the second metal sheet (23), and one end of two springs is fixedly connected in the nitrogen discharge pipe (21), the other ends of the two springs are respectively and fixedly connected with a first metal sheet (22) and a second metal sheet (23), and the nitrogen discharging pipe (21) is matched with the cutting knife (24).