CN108790096B - Extrusion machine - Google Patents

Abstract

The invention discloses an extruder, which comprises a hopper, wherein a plurality of supports for supporting a screen plate are arranged on the inner wall of the hopper, the supports are all connected on the inner wall of the hopper in a sliding way, connecting blocks are fixedly arranged on the inner wall of the hopper below the supports, working springs are fixedly arranged at the bottoms of the supports, one ends of the working springs, which are far away from the supports, are fixedly connected with the connecting blocks, and lifting devices for controlling the supports to slide up and down along the inside of the hopper are arranged at the bottoms of the connecting blocks; the extruder can realize the filtration of impurities in materials, ensures the extrusion molding quality of the materials, prevents abrasion of a screw rod, an extrusion cylinder and the like, and can control the screen plate to have a bouncing effect under the working state, so that the materials are prevented from accumulating on the surface of the screen plate, and the materials smoothly enter the machine barrel through the screen plate.

Description

Extrusion machine

Technical Field

The invention relates to the field of plastic processing mechanical equipment, in particular to an extruder.

Background

The main machine of the plastic extruder is an extruder which consists of an extrusion system, a transmission system and a heating and cooling system, wherein the extrusion system comprises a screw, a machine barrel, a hopper, a machine head and a die, and plastic is plasticized into a uniform melt through the extrusion system, and the machine head is continuously extruded by the screw under the pressure established in the process.

In the process, when powder or granular materials are fed into the hopper, part of impurities and some raw materials which are not stirred are not mixed into the hopper, and if the impurities and the raw materials which are not stirred are mixed into the raw materials and flow into the hard impurities, the impurities and the raw materials enter the extruding cylinder, so that the quality of the extruding materials can be influenced, the screw, the extruding cylinder and the like can be abraded, and the service life of equipment is shortened.

In order to solve the problem, a solution is known in the prior art, such as an extruder (application number: 201620658987.0) disclosed in the patent application text net, comprising a hopper, the hopper being of an inverted cone shape, the inner wall of the hopper being provided with at least four seats, each having an arc adapted to the inner wall of the hopper, the seats being fixed to the hopper, each seat being arranged on the same horizontal plane; each support comprises a bottom plate and an electromagnet, and the electromagnet is fixed on the upper surface of the bottom plate; a circular screen is arranged on the support and is adsorbed on the electromagnet; the support on the same horizontal plane is used for placing the screen, the electromagnet is turned on during working, the screen is adsorbed on the support through the electromagnet, the stability of the screen is guaranteed, the electromagnet is turned off when the screen needs to be replaced, and the screen is directly taken out; the mode of adding the screen mesh in the hopper can ensure that partial impurities in the materials and some raw materials which are not stirred are filtered on the screen mesh and cannot fall into an extrusion system, so that the quality of the extrudate cannot be influenced, and the screw, the extrusion cylinder and the like cannot be abraded.

In the invention, the middle part of the screen is an elastic screen made of elastic materials so as to generate jumping due to elasticity during operation and realize a vibration effect; however, the micro deformation of the material is utilized to realize the bouncing effect in the working process, the bouncing effect is not obvious, the filtering of the material can not be realized well, and the situation that the material is accumulated on the screen can possibly occur.

Disclosure of Invention

The invention aims to provide an extruder which has the advantages that the raw materials which are not crushed or the hard impurities in the materials can be filtered, and the bouncing effect in the working process can be improved, so that the materials can be filtered better and smoothly fall into a machine barrel.

The technical aim of the invention is achieved through the following technical scheme that the extruder comprises a hopper, a plurality of supports for supporting a screen plate are arranged on the inner wall of the hopper, the supports are connected onto the inner wall of the hopper in a sliding manner, connecting blocks are fixedly arranged below the supports on the inner wall of the hopper, working springs are fixedly arranged at the bottoms of the supports, one ends of the working springs, which are far away from the supports, are fixedly connected with the connecting blocks, lifting devices for controlling the supports to slide up and down along the inside of the hopper are arranged at the bottoms of the connecting blocks, the lifting devices comprise rolling bearings fixedly arranged on the inner wall of the hopper and positioned under the connecting blocks, rotating shafts are fixedly arranged on inner rings of the rolling bearings, two ends of each rotating shaft penetrate through the hopper and are respectively communicated with the outside and the inside of the hopper, driven rods perpendicular to the rotating shafts are hinged at the positions, close to the circumferential edge end positions, of one ends of the rotating shafts, which are far away from the rotating shafts, are hinged with the bottoms of the supporting blocks, and the working springs, and are connected with the bottoms of the supports through detachable connecting devices.

Through adopting the technical scheme, the material is put into the hopper through the upper end of the hopper and filtered through the sieve plate, in the process, the manual rotation drive handle rotates the rotating shaft to drive the driven rod to rotate with the circumference of the hinged end of the rotating shaft, the end of the driven rod, which is far away from the rotating shaft, does vertical linear motion in the circumference rotation of the driven rod and drives the support to slide along the inner wall of the hopper vertically, when the support slides upwards under the drive of the driven rod, the working spring is stretched, then the control of the drive handle is released, the support slides downwards under the action of gravity, the working spring is compressed, in the process, the working spring bounces under the elastic deformation property of the working spring, namely, the material falling onto the surface of the sieve plate is dispersed in the bounce process of the sieve plate, so that the material can smoothly fall into the machine barrel through the sieve plate, accumulation can not be formed on the sieve plate, and under the action of the effect of the sieve plate, the mixed impurities in the material and the material which are not stirred are accumulated on the sieve plate can not enter the machine barrel, thus influencing the extrusion molding work; after the extrusion work is finished, the sieve plate can be taken out from the hopper through the detachable connecting device, and the sieve plate is placed into the hopper after the impurities are cleaned up, so that the next filtering is convenient.

The invention is further provided with: the number of the supports is four, and the supports are respectively connected to the inner wall of the hopper in a two-to-two symmetrical sliding manner.

Through adopting above-mentioned technical scheme, the structure of four supports evenly sets up in the hopper, when not extravagant material, enough can realize the support to the sieve plate.

The invention is further provided with: the support is provided with a storage groove, the detachable connecting device comprises extension columns which are respectively and fixedly arranged on the peripheral wall of the sieve plate, the extension columns are respectively and correspondingly embedded in the storage groove, one of the extension columns is fixedly provided with a compression spring on the peripheral side wall of the extension column, one end of the compression spring, which is far away from the extension column, is fixedly provided with a limit column, and the inner side groove wall of one storage groove is provided with a through hole for the limit column to penetrate.

Through adopting above-mentioned technical scheme, when settling the sieve in the hopper for the extension post is all inlayed and is put the thing inslot that corresponds, and one of them extension post that has compression spring and spacing post is inlayed and is put the in-process of thing inslot, and spacing post is contradicted with putting thing inslot cell wall, and compression spring is compressed, after the extension post is inlayed completely and is put the thing inslot, and spacing post slides to through-hole department, and spacing post runs through the through-hole and communicates with each other with the outside, compression spring resumes deformation, so as to realize the locking of extension post in putting the thing inslot, realized the locking of sieve on the support promptly, simple structure, convenient operation.

The invention is further provided with: the cross section of hopper hole is square, the hopper inner wall is located the upper end of support and all is equipped with the guide plate that prevents that the material from falling into on the support, the hopper inner wall is close to guide plate department and is equipped with the adjusting device of control guide plate, is convenient for take out in the sieve follow hopper.

Through adopting above-mentioned technical scheme, when throwing in the hopper with the material, under the effect of guide plate, can avoid the material to fall to the support and extend on the post, the condition that can't get into in the barrel smoothly takes place, has reduced the waste of material.

The invention is further provided with: the adjusting device comprises working grooves which are arranged on the inner wall of the hopper and are respectively positioned at the upper ends of the supporting seats, the top of the guide plate is hinged to the top ends of the working grooves, a connecting rod is hinged to one surface of the guide plate, which is close to the working grooves, the connecting rod penetrates through the hopper and is communicated with the outside, one end of the connecting rod, which is positioned outside the hopper, is provided with a magnet I, and the outer side wall of the hopper is provided with a magnet II which is adsorbed with the magnet I.

By adopting the technical scheme, through the control connecting rod, when the connecting rod is pushed, one end of the guide plate can be controlled to move towards the direction far away from the working groove, so that the shielding effect on the support is realized, and the material is prevented from falling onto the support; when the first magnet and the second magnet are mutually adsorbed, the guide plate can be fixed at the position, the guide plate is always in the guide effect on the materials, and the materials are prevented from falling onto the support.

The invention is further provided with: the connecting rod is hinged on the guide plate and is close to the bottom.

Through adopting above-mentioned technical scheme, when the articulated bottom position department that sets up at the guide plate of connecting rod, the guide plate is kept away from working groove position removal in promotion connecting rod control to realize shielding the support and when the water conservancy diversion work to the material, more laborsaving convenience.

The invention is further provided with: the lower end of the sieve plate is provided with baffle plates parallel to the hopper near the lifting device.

Through adopting above-mentioned technical scheme, under the effect of baffle, can avoid the material that passes through the sieve smoothly to fall to elevating gear on, further avoid the waste of material.

The invention is further provided with: and a sealing gasket is fixedly wrapped on the peripheral wall of the sieve plate.

Through adopting above-mentioned technical scheme, under sealed effect of filling up, the sealed contact between sieve and the hopper inner wall that realizes that the material is directly fallen into in the barrel through the clearance between sieve and the hopper is avoided to under the effect of foam-rubber cushion, in the in-process of placing the sieve in the hopper or taking out from the hopper, effectively avoided the conflict wearing and tearing of sieve and hopper inside wall, prolonged the life of both.

The invention is further provided with: the outer circumferential surfaces of the extending columns are wrapped with sponge mats.

By adopting the technical scheme, under the action of the foam-rubber cushion, when the extension column is embedded into the storage groove, the foam-rubber cushion fills the gap of the storage groove, so that impurities are prevented from accumulating in the storage groove; meanwhile, the sponge cushion can enable the extension column to be compacter to be embedded in the storage groove.

In summary, the invention has the following beneficial effects:

1. The method can realize the filtration of impurities in the materials, ensure the extrusion molding quality of the materials, and avoid the abrasion of a screw, an extrusion cylinder and the like;

2. In the process that the material falls onto the sieve plate for filtering, the sieve plate bounces under the action of the lifting device, so that the material is prevented from being in a stacked state all the time on the surface of the sieve plate, and the material smoothly passes through the sieve plate and enters the machine barrel;

3. The installation and the disassembly of the sieve plate in the hopper are realized through a simple structure, so that the filtering of materials and the cleaning of the sieve plate are facilitated;

4. the material can be effectively prevented from falling onto the support to form accumulation through the structure of adding the bill, so that the waste of the material and the blockage of the storage groove are caused;

5. under the effect of baffle, can avoid falling to elevating gear again through the material of sieve and cause the accumulation on elevating gear, further avoid the extravagant and the jam of structure of material.

Drawings

FIG. 1 is a schematic view of the overall structure of the present extruder;

FIG. 2 is a top view of the hopper of example 1;

FIG. 3 is an enlarged view of a portion of FIG. 2A;

FIG. 4 is a schematic view showing the internal structure of the hopper in example 1;

FIG. 5 is an enlarged view of a portion of B in FIG. 4;

FIG. 6 is a schematic view showing the internal structure of the hopper in example 2;

fig. 7 is a top view of the hopper in example 2.

In the figure: 1. a hopper; 11. a support; 111. a storage groove; 12. a connecting block; 13. a working spring; 14. a deflector; 15. a barrel; 16. a track groove; 2. a sieve plate; 21. a baffle; 22. a sealing gasket; 3. a lifting device; 31. a rolling bearing; 32. a rotating shaft; 33. a drive handle; 34. a driven rod; 4. a detachable connection device; 41. an extension column; 411. a sponge cushion; 42. a compression spring; 43. a limit column; 44. a through hole; 5. an adjusting device; 51. a working groove; 52. a connecting rod; 53. a first magnet; 54. and a second magnet.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Example 1: an extruder, as shown in figure 1, mainly comprises a hopper 1 for feeding materials, wherein the lower end of the hopper 1 is connected and communicated with a machine barrel 15, a driving screw is arranged in the machine barrel 15, the materials are put into the hopper 1 through the upper end of the hopper 1 and fall on the driving screw in the machine barrel 15, and extrusion of the materials is completed through an extruder head which is continuously connected with the screw and is pressurized and plasticized into uniform melt in the conveying process of the driving screw under the pressure established in the process.

As shown in fig. 2 and 4, the cross section of the inner hole of the hopper 1 is square, the four surfaces of the inner wall of the hopper 1 are respectively provided with a track groove 16, the track grooves 16 are respectively connected with a support 11 in a sliding way, and the supports 11 are symmetrical in pairs; the support 11 is provided with a storage groove 111, the structure of the support 11 can be used for supporting the screen plate 2, and at the moment, the screen plate 2 and the support 11 are connected and installed through the detachable connecting device 4.

As shown in fig. 2 and 3, the detachable connection device 4 comprises extension columns 41 fixedly arranged on the outer peripheral wall of the screen plate 2, the extension columns 41 are respectively and correspondingly embedded in the storage slots 111, a compression spring 42 is fixedly arranged on the outer peripheral side wall of one of the extension columns 41, a limit column 43 is fixedly arranged at one end of the compression spring 42 away from the extension column 41, a through hole 44 for the limit column 43 to penetrate is arranged on the inner side slot wall of one of the storage slots 111, and a sponge cushion 411 is wrapped on the outer peripheral wall of each extension column 41, and when the extension column 41 is embedded in the storage slot 111, the sponge cushion 411 fills up the gap in the storage slot 111.

Meanwhile, as shown in fig. 4 and 5, connecting blocks 12 are fixedly arranged on the inner wall of the hopper 1 and located under the support 11, working springs 13 are fixedly arranged at the bottoms of the support 11, one ends, far away from the support 11, of the working springs 13 are fixedly connected with the connecting blocks 12, and lifting devices 3 for controlling the support 11 to slide up and down along the inside of the hopper 1 are arranged at the bottoms of the connecting blocks 12.

As shown in fig. 5, the lifting device 3 comprises a rolling bearing 31 fixedly arranged on the inner wall of the hopper 1 and located under the connecting block 12, a rotating shaft 32 is fixedly arranged on the inner ring of the rolling bearing 31, both ends of the rotating shaft 32 penetrate through the hopper 1 and are respectively communicated with the outside and the inside of the hopper 1, a driving handle 33 for controlling the rotating shaft 32 to rotate is fixedly arranged at one end of the rotating shaft 32 located outside the hopper 1, a driven rod 34 perpendicular to the rotating shaft 32 is hinged at one end of the rotating shaft 32 located inside the hopper 1, the driven rod 34 is hinged at the position, close to the circumferential edge, on the end face of the rotating shaft 32, and the driven rod 34 slides to penetrate through the connecting block 12 and the working spring 13 and then is hinged with the bottom of the support 11.

The specific embodiment is as follows: before the extruder works, the screen plate 2 needs to be installed in the extruder, namely, the screen plate 2 is arranged on the support 11, each extending column 41 of the screen plate 2 is respectively embedded in the object placing groove 111, the extending column 41 with the limiting column 43 is firstly abutted against the inner side groove wall of the object placing groove 111 in the process of being completely embedded in the object placing groove 111, under the abutting action, the compression spring 42 is completely compressed, when the extending column 41 is completely embedded in the object placing groove 111, the limiting column 43 slides to the through hole 44 along the inner side groove wall of the object placing groove 111, at the moment, the limiting column 43 is embedded in the through hole 44 and is communicated with the outside, and meanwhile, the compression spring 42 is deformed in a recovery mode, and at the moment, the extending column 41 can be locked in the object placing groove 111, namely, the connection locking of the screen plate 2 on the support 11 is realized.

When the screen plate 2 is installed and connected on the support 11, the support 11 slides to the bottommost end of the track groove 16 under the gravity action of the screen plate 2, and the working spring 13 is compressed at the moment; the materials are put into the hopper 1 through the upper end of the hopper 1, the materials firstly fall on the surface of the sieve plate 2 and are filtered through the sieve plate 2, in the process, the driving handle 33 is manually rotated to control the rotation of the rotating shaft 32, and at the moment, the rotating shaft 32 can be easily controlled to rotate under the action of the rolling bearing 31; the rotation of the rotating shaft 32 will drive the driven rod 34 hinged to the rotating shaft to rotate circumferentially, and the driven rod 34 slides through the connecting block 12 and then is hinged to the support 11, and at this time, the driven rod 34 can drive the support 11 to slide linearly up and down along the inner wall of the hopper 1.

When the driving handle 33 is controlled to rotate and the support 11 slides upwards under the drive of the driven rod 34, the working spring 13 is stretched, when the support 11 slides to the uppermost end of the track groove 16, the support 11 cannot move upwards, namely continuous co-rotation of the driving handle 33 cannot be realized at the moment, the control of the driving handle 33 is released, the support 11 slides downwards under the action of gravity, the working spring 13 is compressed, after the working spring 13 is fully compressed, the working spring 13 can bounce up and down under the action of inertia and elasticity of the working spring 13 in the process, the whole bounce of the sieve plate 2 is realized, so that materials falling onto the surface of the sieve plate 2 are dispersed in the bounce process of the sieve plate 2, accumulation cannot be formed at a certain position on the sieve plate 2, and the materials can smoothly fall into the machine barrel 15 through the sieve plate 2 into a conveying extrusion stage; under the action of the sieve plate 2, impurities mixed in the materials and the materials which are not crushed are accumulated on the sieve plate 2 and cannot enter the machine barrel 15 to influence extrusion molding work.

After the extrusion work is finished, the screen plate 2 can be taken out from the hopper 1 through the detachable connecting device 4, namely, the limiting column 43 is required to be pressed inwards at the moment so as to be embedded into the storage groove 111, the compression spring 42 is compressed again at the moment, then the screen plate 2 can be taken out from the support 11, impurities are cleaned, and then the screen plate 2 is mounted in the hopper 1 again according to the mode, so that the next filtering of materials is facilitated; in order to facilitate the removal of the screen plate 2 from the hopper 1 by the staff, the support 11 is arranged on the inner wall of the hopper 1 close to the upper opening.

In this embodiment, as shown in fig. 2 and 4, since the lifting device 3 is provided on the hopper 1 in four places, and can respectively control the operation, that is, when the lifting device 3 with different directions can be controlled to realize the bouncing effect of the screen plate 2, the bouncing effect of the screen plate 2 is more obvious, and the filtering of materials is more comprehensive.

In this embodiment, as shown in fig. 2, the outer side walls of the sieve plates 2 are all covered with sealing gaskets 22, and when the sieve plates 2 are mounted on the support 11, the sealing gaskets 22 all abut against the inner side walls of the hoppers 1, so that sealing between the hoppers 1 of the sieve plates 2 can be realized, and impurities in materials are prevented from directly entering the machine barrel 15 through gaps between the sieve plates 2 and the hoppers 1; moreover, under the action of the sealing gasket 22, the condition that the sieve plate 2 is in interference abrasion with the inner wall of the hopper 1 is not worried about in the process of installing and detaching the sieve plate 2.

In this embodiment, as shown in fig. 3, the outer circumferential walls of the extending columns 41 are all wrapped with the sponge pads 411, after the extending columns 41 are respectively embedded in the storage slots 111, the sponge pads 411 will fill the gaps in the storage slots 111, so that the extending columns 41 can be tightly embedded in the storage slots 111, and meanwhile, the contact abrasion between the extending columns 41 and the inner side slot walls of the storage slots 111 can be avoided, and meanwhile, under the action of the sponge pads 411, the gaps in the storage slots 111 can be filled, so that the material impurities are further prevented from falling into the storage slots 111, the waste of materials is avoided, and meanwhile, the blockage of the storage slots 111 is also avoided.

Example 2: an extruder is different from embodiment 1 in that, since some materials fall onto the support 11 to form a pile on the support 11 during the process of feeding the materials into the hopper 1 through the upper end opening of the hopper 1, the materials are wasted at this time, and in order to avoid this phenomenon, the upper ends of the inner walls of the hopper 1 located on the support 11 are provided with baffle plates 14 for preventing the materials from falling onto the support 11, as shown in fig. 6 and 7, the baffle plates 14 are adjusted in the hopper 1 by the adjusting device 5, so as to realize the diversion of the materials, prevent the materials from falling onto the support 11, and control the baffle plates 14 to give up a space for the screen plate 2 to be smoothly taken out from the hopper 1.

As shown in fig. 6 and 7, the adjusting device 5 comprises a working groove 51 arranged on the inner wall of the hopper 1 and respectively positioned at the upper end of the support 11, the top of the guide plate 14 is hinged at the top end in the working groove 51, the guide plate 14 is close to one surface of the working groove 51 and is hinged at the bottom position, a connecting rod 52 is arranged at the connecting rod 52, the connecting rod 52 penetrates through the hopper 1 and is communicated with the outside, a first magnet 53 is arranged at one end of the connecting rod 52 positioned outside the hopper 1, and a second magnet 54 adsorbed by the first magnet 53 is arranged on the outer side wall of the hopper 1.

The specific embodiment is as follows: the connecting rod 52 can be pushed to control the bottom end part of the guide plate 14 to move away from the working groove 51, the connecting rod 52 is pushed to enable the first magnet 53 and the second magnet 54 to be mutually adsorbed, the guide plate 14 can be fixed at the position, at the moment, the guide plate 14 is in an inclined state in the hopper 1, the guide plate 14 is in a shielding state of the support 11, when materials enter the hopper 1 through an upper end opening of the hopper 1, the materials can be contacted with the surface of the guide plate 14, the materials contacted with the guide plate 14 can fall onto the sieve plate 2 along the surface of the guide plate 14 and cannot be contacted with the support 11, and therefore the phenomenon that the materials are stacked on the support 11 is avoided, and waste is caused.

When the extruder is finished and the screen plate 2 needs to be taken out from the hopper 1 for cleaning, the connecting rod 52 is pulled to drive the guide plate 14 to move into the working groove 51, and the screen plate 2 is not blocked from being taken out.

In the embodiment, baffles 21 parallel to the hopper 1 are arranged at the lower end of the screen plate 2 close to the lifting device 3; under the effect of the baffle 21, the material which smoothly passes through the sieve plate 2 can be prevented from falling onto the lifting device 3, and the waste of the material is further avoided.

The present embodiment is only for explanation of the present invention and is not to be construed as limiting the present invention, and modifications to the present embodiment, which may not creatively contribute to the present invention as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present invention.

Claims (4)

1. The utility model provides an extruder, includes hopper (1), be equipped with a plurality of support (11) that supply sieve (2) to put up on hopper (1) inner wall, its characterized in that: the support (11) is connected on the inner wall of the hopper (1) in a sliding way, the connecting blocks (12) are fixedly arranged below the support (11) on the inner wall of the hopper (1), the bottom of the support (11) is fixedly provided with the working springs (13), one ends of the working springs (13) far away from the support (11) are fixedly connected with the connecting blocks (12), the bottom of the connecting blocks (12) is provided with the lifting device (3) for controlling the support (11) to slide up and down along the inside of the hopper (1), the lifting device (3) comprises a rolling bearing (31) fixedly arranged on the inner wall of the hopper (1) and positioned under the connecting block (12), a rotating shaft (32) is fixedly arranged at the inner ring of the rolling bearing (31), both ends of the rotating shaft (32) penetrate through the hopper (1) and are respectively communicated with the outside and the inside of the hopper (1), one end of the rotating shaft (32) positioned at the outside of the hopper (1) is fixedly provided with a driving handle (33) for controlling the rotating shaft (32) to rotate, one end surface of the rotating shaft (32) positioned at the inside of the hopper (1) is hinged with a driven rod (34) perpendicular to the rotating shaft (32) at the position close to the circumferential edge, one end of the driven rod (34) far away from the rotating shaft (32) slides through the connecting block (12) and the working spring (13) and then is hinged with the bottom of the support (11), and the sieve plate (2) is connected with the support (11) through the detachable connecting device (4); the four supports (11) are respectively and symmetrically connected to the inner wall of the hopper (1) in a sliding way; the detachable connecting device (4) comprises extension columns (41) which are fixedly arranged on the outer circumferential wall of the sieve plate (2), the extension columns (41) are correspondingly embedded in the storage grooves (111) respectively, one of the outer circumferential side walls of the extension columns (41) is fixedly provided with a compression spring (42), one end, far away from the extension columns (41), of the compression spring (42) is fixedly provided with a limit column (43), and the inner side groove wall of one storage groove (111) is provided with a through hole (44) for the limit column (43) to penetrate; the cross section of the inner hole of the hopper (1) is square, guide plates (14) for preventing materials from falling onto the support (11) are arranged at the upper ends of the inner walls of the hopper (1) and are positioned at the upper ends of the supports (11), and an adjusting device (5) for controlling the guide plates (14) is arranged at the position, close to the guide plates (14), of the inner walls of the hopper (1) so as to facilitate the screen plates (2) to be taken out from the hopper (1); the adjusting device (5) comprises working grooves (51) which are arranged on the inner wall of the hopper (1) and are respectively positioned at the upper ends of the supports (11), the top of the guide plate (14) is hinged to the top end in the working grooves (51), a connecting rod (52) is hinged to one surface, close to the working grooves (51), of the guide plate (14), the connecting rod (52) penetrates through the hopper (1) and is communicated with the outside, one end, positioned outside the hopper (1), of the connecting rod (52) is provided with a first magnet (53), and a second magnet (54) which is adsorbed with the first magnet (53) is arranged on the outer side wall of the hopper (1); the connecting rod (52) is hinged on the guide plate (14) near the bottom.

2. An extruder as claimed in claim 1, wherein: the lower ends of the sieve plates (2) are provided with baffle plates (21) which are parallel to the hopper (1) at positions close to the lifting device (3).

3. An extruder as claimed in claim 1, wherein: and a sealing gasket (22) is fixedly wrapped on the peripheral wall of the sieve plate (2).

4. An extruder as claimed in claim 1, wherein: the outer circumferential surfaces of the extension columns (41) are wrapped with sponge pads (411).