Outlet backpressure mechanism of screw extruder

Abstract

The utility model relates to the technical field of screw extrusion, in particular to an outlet back pressure mechanism of a screw extruder, which comprises a back cone component, a connecting component and a driving mechanism, the back cone assembly comprises a back cone and a connecting ring, the back cone is formed by combining two half cones, a connecting disc extending outwards is arranged at the end of the back cone, and the connecting disc is detachably connected with the connecting ring; the connecting assembly comprises a push ring and a shell cover, the push ring is connected with the connecting disc through the shell cover, the driving mechanism is connected with the push ring, and idler wheels are further arranged between the push ring and the connecting ring. The back cone assembly is formed by combining the two half cones and is of a modular design, when replacement or cleaning is needed, the back cone assembly can be easily disassembled and reassembled, overall replacement is not needed, the maintenance difficulty and cost are reduced, and the technical problem that an existing tail cone back pressure unit is tedious to disassemble and assemble can be solved.

Description

Technical Field

[0001] The utility model relates to the technical field of screw extrusion, in particular to an outlet back pressure mechanism of a screw extruder. Background Art

[0002] The screw extrusion dehydrator is a common dehydration equipment. It transports the dehydrated material from one end of the cylindrical mesh cage to the other end through the rotating spiral blades, and continuously compresses the space where the material is located in the mesh cage during the transportation process to achieve material extrusion dehydration. Water is discharged from the pores on the mesh cage, and the material residue is discharged through the discharge port at the other end of the mesh cage. In order to increase the pressure of the material in the mesh cage and improve the dehydration effect of the material, an outlet baffle is usually set at the discharge port of the mesh cage. The outlet baffle blocks the material residue discharged through the discharge port, increases the resistance to the discharge of the material in the mesh cage, thereby increasing the pressure of the material in the mesh cage and ensuring the dehydration effect of the material.

[0003] For example, the invention patent with publication number CN115534388A discloses a screw extrusion dehydrator, which provides a tail cone back pressure unit, including a cone plug and an air spring, and the cone plug blocks the outer side of the discharge port under the push of the air spring; however, the tail cone back pressure unit still has the following technical problems during actual use: the plugging cone runs under pressure for a long time and frequently rubs and squeezes with the material. If the material contains a large number of solid particles, the wear of the cone plug will be accelerated; and the existing cone plug is an integral structure. If it needs to be replaced, it is necessary to first disassemble the connecting structure at the rear end of the cone plug before the cone plug can be removed from the spiral shaft, and the disassembly and assembly is relatively cumbersome; in addition, the cone plug is slidably connected to the tail support through a pushing rod, and a spring is arranged at its rear end. After long-term operation, the stability of the tail cone back pressure structure will decrease, thereby reducing the service life. Utility Model Content

[0004] The utility model provides an outlet back pressure mechanism for a screw extruder, which can solve the technical problem of complicated assembly and disassembly of the existing tail cone back pressure unit.

[0005] This application provides the following technical solutions:

[0006] The outlet back pressure mechanism of the screw extruder includes a back cone assembly, a connecting assembly and a driving mechanism; the back cone assembly includes a back cone and a connecting ring, the back cone is composed of two half cones, the end of the back cone is provided with a connecting disk extending outward, and the connecting disk is detachably connected to the connecting ring; the connecting assembly includes a push ring and a shell cover, the push ring is connected to the connecting disk through the shell cover, the driving mechanism is connected to the push ring, and a roller is also provided between the push ring and the connecting ring.

[0007] Beneficial effects:

[0008] 1. Easy to disassemble and assemble: The back cone assembly is composed of two half cones with a modular design. When replacement or cleaning is needed, it can be easily disassembled and reassembled without the need for overall replacement, reducing the difficulty and cost of maintenance. In addition, the detachable connection between the connecting plate and the connecting ring further enhances the convenience of disassembly and assembly, allowing quick maintenance or adjustment, and improving the flexibility and efficiency of the equipment.

[0009] 2. By setting a roller between the push ring and the connecting ring, when the equipment generates vibration during operation, the direct friction between the components can be reduced, the friction loss is reduced, and the service life of the components is extended.

[0010] 3. The push ring and the connecting ring are connected by a shell cover. Compared with the existing connection through a push rod, the shell cover connection method has a more uniform force and can also protect the connecting part, which is beneficial to ensure the stability of the connection between the two and improves the pressure resistance and overall stability of the back pressure mechanism.

[0011] Furthermore, the cone connection surfaces of the two half cones are provided with hook grooves that cooperate with each other, and the connection between the two connection plates is also provided with an arc-shaped reinforcement block.

[0012] Beneficial effect: By setting the hook grooves that cooperate with each other, the stability of the two semi-cone connection surfaces is further strengthened, and the arc-shaped reinforcement block is set at the connection of the connection plate, which is beneficial to improve the stability and strength of the overall structure of the back cone.

[0013] Furthermore, the connecting plate is connected to the connecting ring by bolts, and the bolts are arranged in two layers, the inner layer of bolts is located inside the connecting ring and passes into the back cone, and the outer layer of bolts is located outside the connecting ring and connected to the connecting plate.

[0014] Beneficial effects: The connecting plate and the connecting ring are fixed by bolts, which is convenient for disassembly and assembly; the bolts are arranged in two layers to ensure the strength and stability of the connection and avoid loosening after long-term use.

[0015] Furthermore, it also includes a guide rod, one end of which is connected to the push ring, and the other end passes through the rear plate of the extruder. A guide cylinder is arranged on the side of the rear plate away from the push ring, and the guide rod is slidably arranged in the guide cylinder.

[0016] Beneficial effect: By setting the guide rod and the guide cylinder, the movement of the back cone can be guided and limited.

[0017] Furthermore, ear plates are symmetrically arranged on the push ring, and the power output end of the driving mechanism is connected to the ear plates.

[0018] Beneficial effect: symmetrical ear plates are provided and the driving mechanism is connected to the ear plates, which is conducive to ensuring uniform force on both sides of the push ring.

[0019] Furthermore, the driving mechanism is a hydraulic cylinder, which is arranged on the rear plate of the extruder, and the piston rod of the hydraulic cylinder passes through the rear plate and is connected to the ear plate, and the piston rod is slidably connected to the rear plate.

[0020] Beneficial effect: The back cone is driven to move by a hydraulic cylinder. Compared with the existing method of using an air spring to provide back pressure, the hydraulic cylinder can provide more precise pressure control and can be digitized. The hydraulic cylinder also has higher stability and durability, fast dynamic response, and can quickly adapt to changes in operating conditions.

[0021] Furthermore, the shell cover is U-shaped, and two opposite side walls of the shell cover are respectively connected to the push ring and the connecting plate.

[0022] Beneficial effect: The shell cover connection can not only ensure the stability of the connection, but also protect the connection section, and the end of the shell cover close to the back cone can block the material and reduce the accumulation of materials at the rear end of the back cone.

[0023] Furthermore, weight-reducing holes are provided on the shell cover.

[0024] Beneficial effect: reducing the overall weight of the back pressure mechanism.

[0025] Furthermore, a U-shaped groove is arranged on one side of the push ring close to the connecting ring, and the roller is rotatably arranged in the U-shaped groove, and the outer edge of the roller is in contact with the connecting ring.

[0026] Furthermore, the taper angle of the back cone is 45°.

[0027] Beneficial effects: The 45° taper helps to distribute the pressure on the material more evenly during the extrusion process; and while maintaining a certain back pressure, it can reduce the resistance to material flow, allowing the material to pass through the extrusion area more continuously and stably. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the installation of the back pressure mechanism;

[0029] Figure 2 It is a structural schematic diagram of the back pressure mechanism (the shell cover is omitted in the figure). DETAILED DESCRIPTION

[0030] The following is further described in detail through specific implementation methods:

[0031] The marks in the drawings of the specification include: back cone 1, half cone 11, hook groove 110, connecting plate 12, arc reinforcement block 121, connecting ring 13, connecting assembly 2, push ring 21, ear plate 211, shell cover 22, weight reduction hole 221, hydraulic cylinder 3, guide rod 4, guide cylinder 41, roller 5, U-shaped groove 51, screw shaft 100, and rear plate 101.

[0032] like Figure 1-2As shown, the outlet back pressure mechanism of the screw extruder is sleeved on the screw shaft 100 when in use and is rotatably connected to the screw shaft 100. Specifically, it includes a back cone assembly, a connecting assembly 2 and a driving mechanism; the back cone assembly includes a back cone 1 and a connecting ring 13. In this embodiment, the taper of the back cone 1 is 45°. When in use, the back cone 1 is slidably sleeved on the screw shaft 100; specifically, the back cone 1 is composed of two half cones 11, and the end of the half cone 11 is provided with a connecting disk 12 extending outward, the connecting disk 12 is integrally formed with the half cone 11, and the connecting disk 12 is detachably connected to the connecting ring 13. In order to further improve the stability and connection strength of the back cone 1, the cone connecting surfaces of the two half cones 11 in this embodiment are provided with mutually matching hook grooves 110, and the connection between the two half cones 11 connecting plates 12 is also provided with an arc-shaped reinforcement block 121, and the arc-shaped reinforcement block 121 is respectively fixed on the two connecting plates 12 by bolts; the connecting plate 12 is connected to the connecting ring 13 by bolts. Specifically, in this embodiment, the bolts are arranged in two layers, the inner layer of bolts is located on the inner side of the connecting ring 13 and passes through the back cone 1, and the outer layer of bolts is located on the outer side of the connecting ring 13 and connected to the connecting plate 12.

[0033] The connecting assembly 2 includes a push ring 21 and a shell cover 22. The push ring 21 is slidably mounted on the spiral shaft 100. The push ring 21 is connected to the connecting disk 12 through the shell cover 22. In this embodiment, the shell cover 22 is in two groups and is arc-shaped, mounted on the connecting disk 12 and the push ring 21. Specifically, the shell cover 22 is U-shaped, and a weight reduction hole 221 is provided on the shell cover 22. The two opposite side walls of the shell cover 22 are respectively connected to the push ring 21 and the connecting disk 12 through bolts. In this embodiment, a roller 5 is also provided between the push ring 21 and the connecting ring 13. Specifically, a U-shaped groove 51 is provided on one side of the push ring 21 close to the connecting ring 13. The roller 5 is rotatably arranged in the U-shaped groove 51 through a pin shaft, and the outer edge of the roller 5 is in contact with the connecting ring 13.

[0034] The driving mechanism is connected to the push ring 21; specifically, the push ring 21 is symmetrically provided with ear plates 211, and the power output end of the driving mechanism is connected to the ear plates 211. The driving mechanism in this embodiment is a hydraulic cylinder 3, which is arranged on the rear plate 101 of the extruder, and the piston rod of the hydraulic cylinder 3 passes through the rear plate 101 and is connected to the ear plates 211, and the piston rod is slidably connected to the rear plate 101. This embodiment also includes a guide rod 4, one end of which is connected to the push ring 21, and the other end passes through the rear plate 101 of the extruder. A guide cylinder 41 is provided on the side of the rear plate 101 away from the push ring 21, and the guide rod 4 is slidably arranged in the guide cylinder 41; preferably, two sets of symmetrical guide rods 4 and guide cylinders 41 are provided.

[0035] When in use, the pressure of the hydraulic cylinder 3 is set accordingly according to the pressure of the extrusion section of the screw extruder, and the depth of the taper of the back cone 1 extending into the discharge port is adjusted by controlling the extension length of the piston rod of the hydraulic cylinder 3, thereby adjusting the size of the material discharge port, adjusting the extrusion time and the dehydration effect. The back pressure mechanism of the present application has high structural stability and extends the service life of the equipment; and when the back cone 1 needs to be replaced or cleaned, it can be easily disassembled and reassembled without the need for overall replacement, reducing the difficulty and cost of maintenance; in addition, the driving mechanism uses a hydraulic cylinder 3 to provide back pressure compared to the existing air spring. The hydraulic cylinder 3 can provide more precise pressure control and can be digitized. The stability and durability of the hydraulic cylinder 3 are also higher, the dynamic response is fast, and it can quickly adapt to changes in operating conditions.

[0036] The above is only an embodiment of the utility model. The utility model is not limited to the field involved in this implementation case. The common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the utility model, which should also be regarded as the protection scope of the utility model, and these will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. The outlet back pressure mechanism of the screw extruder comprises a back cone assembly, a connecting assembly and a driving mechanism; characterized in that: The back cone assembly includes a back cone and a connecting ring. The back cone is composed of two half cones. The end of the back cone is provided with a connecting disk extending outward, and the connecting disk is detachably connected to the connecting ring. The connecting assembly includes a push ring and a shell cover. The push ring is connected to the connecting disk through the shell cover, and the driving mechanism is connected to the push ring. A roller is also provided between the push ring and the connecting ring.

2. The outlet back pressure mechanism of the screw extruder according to claim 1, characterized in that: The cone connection surfaces of the two semi-cones are provided with hook grooves that match each other, and the connection of the two connection plates is also provided with an arc-shaped reinforcement block.

3. The outlet back pressure mechanism of the screw extruder according to claim 2, characterized in that: The connecting plate is connected to the connecting ring by bolts, and the bolts are arranged in two layers, the inner layer of bolts is located inside the connecting ring and penetrates into the back cone, and the outer layer of bolts is located outside the connecting ring and connected to the connecting plate.

4. The outlet back pressure mechanism of the screw extruder according to any one of claims 1 to 3, characterized in that: It also includes a guide rod, one end of which is connected to the push ring, and the other end passes through the rear plate of the extruder. A guide cylinder is arranged on the side of the rear plate away from the push ring, and the guide rod is slidably arranged in the guide cylinder.

5. The outlet back pressure mechanism of the screw extruder according to claim 4, characterized in that: Ear plates are symmetrically arranged on the push ring, and the power output end of the driving mechanism is connected to the ear plates.

6. The outlet back pressure mechanism of the screw extruder according to claim 5, characterized in that: The driving mechanism is a hydraulic cylinder, which is arranged on the rear plate of the extruder. The piston rod of the hydraulic cylinder passes through the rear plate and is connected with the ear plate, and the piston rod is slidably connected with the rear plate.

7. The outlet back pressure mechanism of the screw extruder according to claim 6, characterized in that: The shell cover is U-shaped, and two opposite side walls of the shell cover are respectively connected to the push ring and the connecting disk.

8. The outlet back pressure mechanism of the screw extruder according to claim 7, characterized in that: The shell cover is provided with weight-reducing holes.

9. The outlet back pressure mechanism of the screw extruder according to claim 1, characterized in that: A U-shaped groove is arranged on one side of the push ring close to the connecting ring, and the roller is rotatably arranged in the U-shaped groove, and the outer edge of the roller is in contact with the connecting ring.

10. The outlet back pressure mechanism of the screw extruder according to claim 1, characterized in that: The taper of the back cone is 45°.

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