Straw and soil mixed pipe making and field returning equipment

Abstract

A straw and soil mixed pipe making and field returning device comprises an auger and a cutter tooth shaft which are installed in a shell support, a secondary smashing and conveying device, a conical extrusion device and a ditching device which are installed outside the shell support, and the outer end of an extrusion pipe of the conical extrusion device is connected with an arc-shaped guide plate; the outer port of the extrusion pipe is provided with a closing-in type discharge nozzle, the upper part of the closing-in type discharge nozzle is provided with an upper bending part which is bent towards the center of the extrusion pipe, and the two sides of the closing-in type discharge nozzle are provided with side bending parts which are bent towards the center of the extrusion pipe; the end part of the forming rod is fixedly connected with a spiral spring, and the outer end of the spiral spring extends into the arc-shaped material guide plate; a plurality of guide ribs are uniformly distributed on the inner side wall of the extrusion pipe; the equipment can be used for manufacturing fish scale-shaped composite pipes, the water seepage irrigation efficiency is improved, the flexibility of the composite pipes is improved, the overall shape of the pipes conveyed outwards after the pipes are formed is kept, meanwhile, the phenomenon that the composite pipes are broken due to stress concentration generated by rotation is avoided, and the forming quality of the composite pipes is guaranteed.

Description

Technical Field

[0001] The invention relates to the field of straw returning to fields and irrigation, and in particular to equipment for returning straw and soil mixed into pipes to fields. Background Art

[0002] The invention patent with the authorization announcement number CN114027017B discloses a corn straw returning equipment, which digs deep trenches on the ground surface through a trenching device, and continuously feeds soil from the soil inlet to the auger bin through the soil-taking knife on the trenching chain. The knife tooth shaft crushes the corn straw and feeds it into the auger bin from the straw throwing inlet. The auger feeds a certain proportion of soil and straw into the secondary crushing and conveying device. The secondary crushed straw and soil enter the conical mixing from the straw conveying pipeline along the tangential direction under the action of the impeller. The mixed agent, soil and straw sprayed by the nozzle are mixed in the conical mixing bin. After cyclone mixing, the mixture enters the conical extrusion chamber, and the compression auger inside the extrusion chamber squeezes the mixture into the forming extrusion tube. Under the action of the tube forming column, a composite tube of straw and soil is formed, and then discharged from the straw conveying pipeline into the deep trench opened by the trenching device, and the composite tube is buried by the burying device; this equipment can fully automatically perform trenching, crushing and tube making operations. The composite tube made is buried in the deep trench, which can not only directly act on the straw into the deep soil and increase the organic matter content of the deep soil, but also be used as a seepage pipe for underground irrigation of farmland.

[0003] The problem existing in the production operation of the corn straw returning equipment is that when the auger in the conical extrusion device rotates to extrude the mixed material, the mixed material will rotate with the rotation of the auger. Therefore, when the material is extruded to form a composite pipe and reaches the discharge port, the composite pipe still keeps rotating at the discharge port and enters the conveying pipe below. When the friction between the conveying pipe and the composite pipe is greater than the rotational force of the composite pipe itself, it will cause large cracks on the surface of the formed composite pipe, and even twisting phenomenon will occur; and the soil and straw mixed material will generate a large extrusion pressure when entering the extrusion pipe from the conical extrusion bin, which is prone to material accumulation, resulting in poor discharge and deformation of the pipe; at the same time, the extrusion pressure will cause the straw stalks and soil to be more densely combined, resulting in a relatively narrow water seepage gap between the stalks and the soil. After the irrigation water enters the pipe, the speed of seeping out from the gap is slow, and the irrigation efficiency is low, which affects the extrusion molding efficiency and molding quality of the pipe, and needs to be improved. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a straw and soil mixed pipe making and returning to the field equipment.

[0005] The technical solution of the present invention is: A straw and soil mixed pipe-making and returning-to-field equipment, which is characterized in that it includes a auger and a cutter tooth shaft installed inside a housing bracket, a secondary crushing and conveying device, a conical extrusion device, a ditch-opening device and a burying device installed outside the housing bracket. The conical extrusion device includes a conical extrusion chamber, an auger inside the conical extrusion chamber, an extrusion pipe coaxially arranged at the tip of the conical extrusion chamber, and a forming rod arranged at the outer end of the main shaft of the auger. An arc-shaped guide plate arranged obliquely downward is connected to the outer end of the extrusion pipe; a closed-mouth type discharge nozzle integrally in a circular ring shape is provided at the outer port of the extrusion pipe. The upper part of the closed-mouth type discharge nozzle is provided with an upper bending part bent towards the center of the extrusion pipe, and both sides are provided with side bending parts bent towards the center of the extrusion pipe; a spiral spring is fixedly connected to the end of the forming rod. The outer diameter size of the spiral spring matches the inner diameter size of the composite pipe, and the outer end of the spiral spring extends from the extrusion pipe into the arc-shaped guide plate; a plurality of guiding rib strips are evenly distributed on the inner side wall of the extrusion pipe, and the guiding rib strips are arranged along the extrusion direction of the extrusion pipe.

[0006] Preferably, the bending amplitude of the upper bending part is greater than that of the side bending part.

[0007] Preferably, the width of the upper part of the closed-mouth type discharge nozzle is greater than that of the lower part.

[0008] Preferably, the generatrix of the arc-shaped section at the lower part of the closed-mouth type discharge nozzle coincides with the generatrix of the extrusion pipe.

[0009] Preferably, the guiding rib strips are linear optical axes, and the axial direction of the linear optical axes is consistent with the axial direction of the extrusion pipe.

[0010] Preferably, the linear optical axis is a variable-diameter optical axis, and its diameter gradually increases from the inner end to the outer end.

[0011] Preferably, the guiding rib strips are spiral bent shafts, and the spiral direction of the spiral bent shafts is consistent with the rotation direction of the auger inside the conical extrusion device.

[0012] Preferably, the spiral bent shaft is a variable-diameter spiral bent shaft, and its diameter gradually increases from the inner end to the outer end.

[0013] Preferably, the pitch of the spiral bent shaft gradually increases from the inner end to the outer end, so that a linear shaft section consistent with the axial direction of the extrusion pipe is formed at the outer end part of the spiral bent shaft.

[0014] Preferably, the inner end of the spiral spring is provided with a shaft head. The end of the spiral spring is fixedly sleeved on one end of the shaft head. The end of the forming rod is provided with a threaded blind hole, and the other end of the shaft head is threadedly connected into the threaded blind hole. The threaded connection direction of the shaft head and the threaded blind hole is opposite to the rotation direction of the auger.

[0015] The beneficial technical effects of the present invention are: (1) The field returning equipment is provided with a closed-mouth discharging nozzle at the outer end of the extrusion pipe. The composite pipe formed by extrusion is bent downward slightly through its closed-mouth bending structure, and the outer side surface of the composite pipe is continuously scraped. Under the combined action of the downward bending force and the scraping force, the bonding strength between the soil and the straw inside the composite pipe is overcome, and fish-scale bodies are continuously formed, resulting in a fish-scale-shaped composite pipe. After irrigation water enters this composite pipe, it can quickly seep into the water seepage openings between the fish-scale bodies and flow out quickly from the water seepage openings, making up for the problem of slow water seepage speed relying on the gaps between the straws, effectively improving the water seepage irrigation efficiency, and facilitating further promotion and application in the market.

[0016] (2) In the field returning equipment, the spiral spring connected to the forming rod of the auger supports on the inner side surface of the composite pipe. During the process of the composite pipe being extruded and conveyed, the spiral spring rotates with the auger, can contact the inner side surface of the composite pipe from the inside and push the composite pipe spirally, playing an auxiliary conveying role, enabling the composite pipe to be extruded from the extrusion pipe in a timely and smooth manner; and the flexible support of the spiral spring is beneficial to improving the flexibility of the composite pipe, facilitating maintaining the overall shape of the pipe during outward conveyance after forming, and improving the forming quality of the pipe.

[0017] (3) The guiding rib strips uniformly arranged on the inner side surface of the extrusion pipe in the field returning equipment can generate rotational resistance to the composite pipe in the circumferential direction, destroying the rotational inertia of the composite pipe generated with the auger, enabling the composite pipe to be extruded from the extrusion pipe in a basically straight state, effectively solving the phenomenon of fracture of the composite pipe caused by stress concentration generated by rotation, and ensuring the forming quality of the composite pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a three-dimensional structural schematic diagram of the present invention; Figure 2 is a three-dimensional structural schematic diagram of the conical extrusion device of the present invention; Figure 3 is Figure 2 the sectional structural schematic diagram in the A-A direction of Figure 4 is the structural schematic diagram when a fish-scale-shaped composite pipe is extruded inside the extrusion pipe; Figure 5 is a three-dimensional structural schematic diagram of the spiral spring connected to the auger; Figure 6 is a three-dimensional structural schematic diagram of the spiral spring; Figure 7 is one of the three-dimensional structural schematic diagrams of the linear optical axis arranged inside the extrusion pipe; Figure 8 is the other three-dimensional structural schematic diagram of the linear optical axis arranged inside the extrusion pipe; Figure 9 is Figure 8 the front view structural schematic diagram of Figure 10 is Figure 9 the schematic diagram of the sectional structure in the B - B direction; Figure 11 is the three - dimensional structure schematic diagram of a variable - diameter optical axis arranged inside the extrusion pipe; Figure 12 is Figure 11 the front - view structure schematic diagram of; Figure 13 is Figure 12 the schematic diagram of the sectional structure in the C - C direction of; Figure 14 the three - dimensional structure schematic diagram of a spiral bent shaft arranged inside the extrusion pipe; Figure 15 is Figure 14 the front - view structure schematic diagram of; Figure 16 is Figure 15 the schematic diagram of the sectional structure in the D - D direction of; Figure 17 is Figure 16 the schematic diagram of the sectional structure in the E - E direction of; Figure 18 is the three - dimensional structure schematic diagram of a variable - diameter spiral bent shaft arranged inside the extrusion pipe; Figures 19 - 21 is the physical diagram of the present invention.

[0019] In the figure, 1. housing support, 2. conical extrusion device, 3. secondary crushing and conveying device, 4. burying device, 5. trenching device, 21. conical extrusion bin, 22. auger, 23. extrusion pipe, 24. forming rod, 31. spiral spring, 32. shaft head, 33. threaded blind hole, 41. linear optical axis, 42. variable - diameter optical axis, 43. spiral bent shaft, 44. linear shaft section, 45. variable - diameter spiral bent shaft, 5. closed - mouth discharge nozzle, 51. upper bent part, 52. side bent part, 53. lower arc section, 6. composite pipe, 61. fish - scale body, 62. water - seepage opening, 71. arc - shaped guide plate, 72. transition support plate. Specific Embodiments

[0020] Example 1, see the attached Figures 1 - 3 , 7 - 18, a straw and soil mixed pipe - making and field - returning equipment, including an auger 22 and a cutter - tooth shaft installed inside the housing support 1, a secondary crushing and conveying device 3, a conical extrusion device 2, a trenching device 5 and a burying device 4 installed outside the housing support 1. The conical extrusion device 2 includes a conical extrusion bin 21, an auger 22 inside the conical extrusion bin 21, an extrusion pipe 23 coaxially arranged at the tip of the conical extrusion bin 21, and a forming rod 24 arranged at the outer end of the main shaft of the auger 22. The outer end of the extrusion pipe 23 is connected with an arc - shaped guide plate 71 arranged obliquely downward.

[0021] AsFigures 7 - 10 As shown, a number of guiding rib strips are evenly distributed on the inner side wall of the extrusion pipe 23. The guiding rib strips are arranged along the extrusion direction of the extrusion pipe. One end of the guiding rib strip is close to the inner port of the extrusion pipe 23, and the other end is close to the outer port of the extrusion pipe 23. The guiding rib strip is set as a linear optical axis 41, and the axial direction of this linear optical axis 41 is consistent with the axial direction of the extrusion pipe 23. The mixed material enters the extrusion pipe 23 from the conical extrusion device 2 to form a composite pipe 6 material. During this process, the linear optical axes 41 evenly distributed on the inner side of the extrusion pipe 23 can generate rotational resistance to the composite pipe 6 material in the circumferential direction, destroying the rotational inertia of the composite pipe 6 material generated by the auger 22, so that the composite pipe material is basically extruded from the extrusion pipe in a straight line state, effectively solving the phenomenon of fracture of the composite pipe 6 material caused by stress concentration generated by rotation, and ensuring the forming quality of the composite pipe material.

[0022] As Figures 7 - 13 shown, the linear optical axis 41 is set as a variable-diameter optical axis 42, and its diameter gradually increases from the inner end to the outer end. Through the variable-diameter design of the linear optical axis 41, the rotational resistance of the composite pipe 6 material gradually increases during the process of being extruded outward in the extrusion pipe 23, and the rotational inertia of the composite pipe 6 material generated by the auger 22 is released in a stepwise manner from small to large, making the stress release process relatively gentle and conducive to further improving the forming quality of the pipe material.

[0023] As Figures 14 - 17 shown, the guiding rib strip is set as a spiral bent shaft 43. The spiral direction of this spiral bent shaft is consistent with the rotational direction of the auger 22 inside the conical extrusion device 2. The pitch of the spiral bent shaft 43 gradually increases from the inner end to the outer end, so that a linear shaft section 44 consistent with the axial direction of the extrusion pipe 23 is formed at the outer end of the spiral bent shaft 43. The mixed material enters the extrusion pipe 23 from the conical extrusion device 2 in a rotating state and forms a composite pipe 6 material. The spiral bent shafts 43 evenly distributed on the inner side of the extrusion pipe 23 generate rotational resistance to the composite pipe 6 material. Since the spiral direction of the spiral bent shaft 43 is consistent with the rotational direction of the composite pipe 6 material and the pitch gradually increases from the inner end to the outer end, the composite pipe 6 material rotates forward along the spiral direction of the spiral bent shaft 43 when it first enters the extrusion pipe 23. As the pitch increases, the rotational resistance gradually increases, gradually destroying the rotational inertia of the composite pipe 6 material. When the composite pipe 6 material reaches the linear shaft section 44 of the spiral bent shaft 43, the composite pipe 6 material is basically in a straight line state, effectively solving the phenomenon of fracture of the composite pipe 6 material caused by stress concentration generated by rotation, and ensuring the forming quality of the composite pipe 6 material.

[0024] As Figure 18As shown, the spiral bent shaft 43 is a variable-diameter spiral bent shaft 45, whose diameter gradually increases from the inner end to the outer end. Through the variable-diameter design of the spiral bent shaft 43, while the spiral bent shaft 43 itself releases the rotational resistance by means of spiral, the gradually increasing diameter of the spiral bent shaft 43 generates an increasingly larger resistance. The combination of the two can release the rotational inertia generated by the composite pipe 6 material along with the auger 22 in a stepwise manner from small to large, making the stress release process more gentle and conducive to further improving the forming quality of the pipe material.

[0025] Example two, see the appendix Figures 1 - 6 , this example is basically the same as Example one, and the same parts will not be elaborated again. The differences are as follows: A spiral spring 31 is fixedly connected to the end of the forming rod 24 and extends from the extrusion pipe 23 into the arc-shaped material guide plate 71. The outer diameter size of the spiral spring 31 matches the inner diameter size of the composite pipe 6 material, ensuring that the spiral spring 31 can elastically press against the inner side surface of the composite pipe 6. The composite pipe 6 is slidably conveyed through the arc-shaped material guide plate 71, and its opening structure can avoid squeezing the fish scales 61 generated on the composite pipe 6 and prevent affecting the water seepage effect. An arc-shaped transition support plate 72 is provided between the outer ends of the arc-shaped material guide plate 71 and the extrusion pipe 23. The transition support plate 72 is coaxially arranged with the extrusion pipe 23. The support provided by the transition support plate 72 can prevent the composite pipe 6 extrusion pipe 23 from being subjected to excessive stress and causing it to break.

[0026] The fixed end of the spiral spring 31 extends into the extrusion pipe 23 of the conical extrusion device 2 for a certain distance. It can resist the rotational torque and extrusion force when the composite pipe 6 material is extruded at the end of the extrusion pipe 23, prevent the composite pipe 6 material from deforming at the discharge port, help maintain the shape and size stability of the discharge port, and reduce the material accumulation and blockage caused by the deformation of the discharge port.

[0027] A shaft head 32 is provided at the inner end of the spiral spring 31. The end of the spiral spring 31 is sleeved on one end of the shaft head 32 by means of welding fixation. A threaded blind hole 33 is provided at the end of the forming rod 24, and the other end of the shaft head 32 is threadedly connected into the threaded blind hole 33. This shaft head 32 docking structure facilitates the convenient and quick maintenance and replacement of the spiral spring 31 at the operation site and ensures the operation efficiency. The threaded connection direction of the shaft head 32 and the threaded blind hole 33 is opposite to the rotation direction of the auger 22. During the process of the auger 22 spirally extruding and mixing materials to form the composite pipe 6 material, a reverse tightening force on the shaft head 32 can be generated to ensure that the spiral spring 31 is in a stable connection state.

[0028] The working process and principle of the helical spring 31 in this embodiment are as follows: The auger 22 rotates in the conical extrusion device 2 to extrude the mixed material from the extrusion pipe 23. While the composite pipe 6 is formed within the extrusion pipe 23, the helical spring 31 connected to the forming rod 24 supports against the inner side surface of the composite pipe 6. During the extrusion and conveyance of the composite pipe 6, the helical spring 31 rotates with the auger 22, contacts the inner side surface of the composite pipe 6 from the inside and spirally pushes the composite pipe 6, playing a role in assisting the conveyance of the composite pipe 6, enabling the composite pipe 6 to be extruded from the extrusion pipe 23 in a timely and smooth manner. At the same time, the flexible support force generated by the helical spring 31 can improve the flexibility of the composite pipe 6, facilitating the maintenance of the overall shape of the pipe after forming during the outward conveyance, and improving the quality of pipe processing and forming.

[0029] Embodiment Three. Refer to Attachments Figures 1 - 4 7 - 9. This embodiment is basically the same as Embodiment One, and the same parts will not be described again. The differences are as follows: The outer port of the extrusion pipe 23 is provided with a closed - mouth discharge nozzle 5 that is integrally circular - ring - shaped. The upper part of the closed - mouth discharge nozzle 5 is provided with an upper bending part 51 that bends towards the center of the extrusion pipe 23, and both sides are provided with side bending parts 52 that bend towards the center of the extrusion pipe 23. When the composite pipe 6 is extruded from the extrusion pipe 23, the upper bending part 51 can slightly press and bend the composite pipe 6 downwards. At the same time, the upper bending part 51 and the two side bending parts 52 can scrape the outer side surface of the composite pipe 6, increasing the frictional force on the outer side surface of the composite pipe 6 during extrusion. Under the combined action of the downward bending force and the scraping force, the bonding strength between the soil and straw inside the composite pipe 6 is overcome, and fish - scale bodies 61 are continuously formed, resulting in a fish - scale - shaped composite pipe 6.

[0030] The bending amplitude of the upper bending part 51 is greater than that of the side bending part 52, creating a bending difference between the upper bending part 51 and the side bending parts 52. Therefore, the scraping force of the upper bending part 51 is greater than the scraping forces on both sides, which is more conducive to the formation of fish - scale bodies 61 on the outer side surface of the composite pipe 6.

[0031] The width of the upper part of the closed - mouth discharge nozzle 5 is greater than that of the lower part. The width difference between the upper and lower parts can reduce the supporting force of the lower part of the discharge nozzle on the composite pipe 6 and increase the downward scraping force of the upper bending part 51 on the composite pipe 6 Combined with the difference in the bending amplitudes of the upper bending part 51 and the lower bending part, fish - scale bodies 61 with sufficient water - seepage openings 62 can be formed.

[0032] The generatrix of the arc - shaped section 53 at the lower part of the closed - mouth discharge nozzle 5 coincides with the generatrix of the extrusion pipe 23. This design can avoid generating scraping force at the bottom of the composite pipe 6 and ensure the integrity of its bottom structure. It is necessary to ensure that the composite pipe 6 has sufficient structural strength and flexibility to avoid the phenomenon of pipe body fracture during the basic conveyance process.

[0033] The steps for this soil - returning equipment to process and manufacture the fish - scale - shaped composite pipe 6 and perform soil - returning irrigation are as follows: Step 1: The returning equipment moves forward along the cultivated land. The trench digging device 5 at its rear digs a trench. At the same time, the auger 22 in the conical extrusion device 2 rotates to push the wet soil and straw mixture in the conical extrusion bin 21 to be compressed into the extrusion pipe 23; Step 2: The mixture is compressed and compacted in the extrusion pipe 23, and under the action of the forming rod 24 at the center, it forms a composite pipe 6 and is extruded from the closed-mouth discharge nozzle 5; Step 3: While extruding, the inwardly closing and bending structures on the upper part and both sides of the closed-mouth discharge nozzle 5 can slightly bend the composite pipe 6 downward and continuously scrape the outer side of the composite pipe 6. Under the combined action of the bending force and the scraping force, the outer side of the composite pipe 6 is continuously bent and scraped to form fish scale bodies 61. The water seepage openings 62 between the fish scale bodies 61 extend into the pipe wall of the composite pipe 6. After the fish scale-shaped composite pipe 6 is extruded, the transition support plate 72 provides it with a short horizontal support, and then it enters the arc-shaped guide plate 71 downward; Step 4: After the composite pipe 6 is laid in the cultivated land, the burying device 4 backfills the soil into the trench. Then, irrigation water is introduced into the composite pipe 6. During the process of the irrigation water flowing along the composite pipe 6, it will seep out from the small gaps at the inner stubble of the side wall, and at the same time, it can penetrate into the roots of the fish scale bodies 61 and flow out from the water seepage openings 62. Under the combined action of the small gaps at the stubble and the water seepage openings 62 formed by the fish scale bodies 61, the composite pipe 6 forms a high-flow-rate and high-efficiency underground water seepage pipe, realizing uniform irrigation of the cultivated land, making up for the problem of slow water seepage speed relying on the gaps between straws, and effectively improving the water seepage irrigation efficiency.

Claims

1. A straw and soil mixed pipe returning equipment, characterized by: The invention comprises an auger and a knife-tooth shaft installed inside a housing support, and a secondary crushing and conveying device, a conical extrusion device, a trenching device and a burying device installed outside the housing support, and is characterized in that: The conical extrusion device comprises a conical extrusion bin, an auger in the conical extrusion bin, an extrusion tube coaxially arranged at the tip of the conical extrusion bin, and a forming rod arranged at the outer end of the main shaft of the auger, the outer end of the extrusion tube is connected to an arc-shaped material guide plate arranged obliquely downward; the outer end of the extrusion tube is provided with a closed-end discharge nozzle which is generally annular, the upper part of the closed-end discharge nozzle is provided with an upper bending part bent toward the center of the extrusion tube, and both sides are provided with side bending parts bent toward the center of the extrusion tube; a coil spring is fixedly connected to the end of the forming rod, the outer diameter of the coil spring matches the inner diameter of the composite pipe, and the outer end of the coil spring extends from the extrusion tube into the arc-shaped material guide plate; a plurality of guide ribs are evenly distributed on the inner wall of the extrusion tube, and the guide ribs are arranged along the extrusion direction of the extrusion tube.

2. The straw and soil mixed pipe making and returning to the field equipment according to claim 1 is characterized by: The bending amplitude of the upper bending portion is greater than the bending amplitude of the side bending portion.

3. The straw and soil mixed pipe making and returning to the field equipment according to claim 2 is characterized by: The width of the upper part of the closed-end discharge nozzle is greater than the width of the lower part.

4. The straw and soil mixed pipe making and returning to the field equipment according to claim 3 is characterized by: The generatrix of the arc section at the lower part of the closing-end type discharge nozzle coincides with the generatrix of the extrusion tube.

5. The straw and soil mixed pipe making and returning to the field equipment according to claim 1 is characterized by: The guide rib is a linear optical axis, and the axial direction of the linear optical axis is consistent with the axial direction of the extruded tube.

6. The straw and soil mixed pipe making and returning to the field equipment according to claim 5 is characterized by: The linear optical axis is a variable diameter optical axis, and its diameter gradually increases from the inner end to the outer end.

7. The straw and soil mixed pipe making and returning to the field equipment according to claim 1 is characterized by: The guide rib is a spiral bent shaft, and the spiral direction of the spiral bent shaft is consistent with the rotation direction of the auger inside the conical extrusion device.

8. The straw and soil mixed pipe making and returning to the field equipment according to claim 7 is characterized by: The spiral bent shaft is a variable diameter spiral bent shaft, the diameter of which gradually increases from the inner end to the outer end.

9. The straw and soil mixed pipe making and returning to the field equipment according to claim 8 is characterized by: The pitch of the spiral bent shaft gradually increases from the inner end to the outer end, so that the outer end of the spiral bent shaft forms a straight shaft segment consistent with the axial direction of the extruded tube.

10. The straw and soil mixed pipe making and returning to the field equipment according to claim 1 is characterized by: The inner end of the coil spring is provided with an axle head, the end of the coil spring is fixedly sleeved on one end of the axle head, the end of the forming rod is provided with a threaded blind hole, the other end of the axle head is threadedly connected to the threaded blind hole, and the threaded connection direction of the axle head and the threaded blind hole is opposite to the rotation direction of the auger.

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