CN114148024B - Extrusion molding device and extruder - Google Patents

Abstract

The present invention provides an extrusion molding device and an extruder, wherein the extrusion molding device includes an outer shell, which is a cylindrical structure with openings at both ends, and the feed end of the outer shell is provided with a connection portion for connecting with the discharge port of the extrusion equipment; a core shaft is arranged inside the outer shell and forms an annular gap with the outer shell, the core shaft is relatively fixed to the outer shell, and the distance between the outer wall of the tail end of the core shaft and the inner wall of the outer shell is less than or equal to the distance between the outer wall of the head end of the core shaft and the inner wall of the outer shell. With such an arrangement, the discharge speed of each position of the annular gap between the outer shell and the core shaft is consistent, not only can the product of the cylindrical structure be processed, but the product of the cylindrical structure can also be formed into a flat sheet after later cutting. Under the condition that the output rate of the extrusion equipment and the thickness of the processed product are constant, the width of the product is increased compared with the flat molding die in the prior art, and the efficiency and output of the extrusion molding are improved.

Description

Extrusion molding device and extruder

Technical Field

The present invention relates to the technical field of mechanical devices, and in particular to an extrusion molding device and an extruder.

Background Art

As people's awareness of dietary nutrition, health and environmental protection increases, plant-based foods represented by "plant meat" have attracted widespread attention at home and abroad, such as artificial meat made from protein-rich soy products.

At present, an extruder is generally used to extrude the "plant meat" raw materials so that they have a fiber structure similar to animal meat and a soft, elastic and tough taste. The extrusion die of the extruder is the main component of the extruder equipment. The long cooling flat extrusion die in the prior art can often only process flat sheet products. In order to ensure the cooling effect during the molding process, the thickness of the processed product cannot be too large. Due to the boundary effect, the discharge of the material in the middle position of the flow channel of the extrusion die is fast, and the discharge of the material at both ends is slow, resulting in the width of the discharge port of the extrusion die cannot be too large. If the width of the discharge port is too large, it will cause cracking problems in the processed product, affecting the integrity of the product, thereby limiting the width and thickness of the product processed by the extrusion die, thereby limiting the production efficiency and output of the extrusion die.

Summary of the invention

The present invention provides an extrusion molding device and an extruder to solve the above problems.

The present invention provides an extrusion molding device, comprising:

The outer shell is a cylindrical structure with openings at both ends, and the feed end of the outer shell is provided with a connecting portion for connecting with the discharge port of the extrusion device;

The core shaft is arranged inside the shell and forms an annular gap with the shell. The core shaft is relatively fixed to the shell, and the distance between the outer wall of the tail end of the core shaft and the inner wall of the shell is less than or equal to the distance between the outer wall of the head end of the core shaft and the inner wall of the shell.

According to an extrusion molding device provided by the present invention, the axis of the core shaft coincides with the axis of the shell.

According to an extrusion molding device provided by the present invention, the mandrel comprises:

A flow guide portion connected to the shell, the flow guide portion being arranged inside the feed end of the shell;

The forming part can be detachably connected to the guide part.

According to an extrusion molding device provided by the present invention, a guide surface is provided on the outer side surface of one end of the guide portion away from the molding portion, and the distance between the guide surface and the axis of the guide portion gradually increases in a direction approaching the molding portion.

According to an extrusion molding device provided by the present invention, the angle between the guide surface and the axis of the guide portion is 15-60 degrees.

According to an extrusion molding device provided by the present invention, the molding portion includes a first section and a second section, the first section is located upstream of the second section along the feeding direction, the first section and the second section form an integrated structure, and the distance between the outer wall of the first section and the inner wall of the outer shell is greater than the distance between the outer wall of the second section and the inner wall of the outer shell.

According to an extrusion molding device provided by the present invention, a plurality of molding parts can be provided, and any of the molding parts can be detachably connected to the guide part;

The second sections of the plurality of shaped portions have different sizes, and/or the second sections of the plurality of shaped portions have different cross-sectional shapes, and the size of the second section includes a length dimension and/or a cross-sectional dimension of the second section.

According to an extrusion molding device provided by the present invention, a transition slope is provided between the outer side wall of the first section and the outer side wall of the second section, and the angle between the transition slope and the axis of the molding portion is 0-60 degrees.

According to an extrusion molding device provided by the present invention, the tail end of the mandrel is located inside the housing;

Or, the end surface of the tail end of the mandrel is flush with the end surface of the discharge end of the housing;

Alternatively, the tail end of the mandrel is located outside the housing.

An extrusion molding device provided according to the present invention also includes:

A temperature control component is used to control the temperature of the shell and/or the temperature of the core shaft.

According to an extrusion molding device provided by the present invention, the temperature control component comprises:

A first heat exchange part having a first heat exchange channel for heat exchange medium to flow, wherein the first heat exchange part is sleeved on the outside of the shell;

and/or, a second heat exchange portion having a second heat exchange channel for heat exchange medium to flow through, the second heat exchange portion being arranged inside the core shaft;

The first heat exchange part and the second heat exchange part are both provided with a medium inlet and a medium outlet for heat exchange medium to enter and exit.

According to an extrusion molding device provided by the present invention, the first heat exchange part is movably arranged on the outer shell, or the first heat exchange part and the outer shell form an integrated structure.

According to an extrusion molding device provided by the present invention, the first heat exchange channel and the second heat exchange channel extend along a straight line;

Alternatively, the first heat exchange channel and the second heat exchange channel extend along a curve.

An extrusion molding device provided according to the present invention also includes:

The flow dividing plate has a through hole for materials to pass through, and the flow dividing plate is arranged between the guide part and the shell or between the first section and the shell.

According to an extrusion molding device provided by the present invention, the connecting part includes a connecting sleeve whose first end can be connected to the discharge port of the extrusion equipment, the connecting sleeve is sleeved on the outside of the feed end of the outer shell, and a limiting structure is arranged between the second end of the connecting sleeve and the outer shell, and the limiting structure is used to limit the outer shell from escaping from the second end of the connecting sleeve and make the axis of the connecting sleeve coincide with the axis of the outer shell.

The present invention also provides an extruder, comprising the extrusion molding device.

In the extrusion molding device provided by the present invention, the outer shell is connected to the discharge port of the extrusion equipment through a connecting part, and an annular gap is provided between the outer shell and the core shaft. The material output by the extrusion equipment can enter the annular gap between the outer shell and the core shaft, and a product with a cylindrical structure can be output after molding, and the discharge speed at each position of the annular gap between the outer shell and the core shaft is consistent. According to specific needs, the product with a cylindrical structure can also be cut into flat sheets, and the width of the flat sheet product formed by cutting is the circumference of the product with a cylindrical structure. When the output rate of the extrusion equipment and the thickness of the processed product are constant, the width of the product is increased compared with the flat molding mold in the prior art, thereby improving the efficiency and output of the extrusion molding.

Furthermore, the extruder provided by the present invention has the extrusion molding device as described above, and thus also has the various advantages as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic structural diagram of an extrusion molding device provided by the present invention;

FIG. 2 is a second structural schematic diagram of the extrusion molding device provided by the present invention.

Reference numerals:

1: Shell; 2: Guide part; 3: Forming part; 4: Guide surface; 5: First section; 6: Second section; 7: Transition slope; 8: First heat exchange part; 9: First heat exchange channel; 10: Medium inlet; 11: Medium outlet; 12: Diverter plate; 13: Connecting sleeve; 14: Limiting structure; 15: Seal; 16: Second heat exchange channel; 17: Feed end; 18: Discharge end; 19: Head end; 20: Tail end; h: Gap between the outer wall of the second section and the inner wall of the shell; α: Angle between the transition slope and the axis of the forming part.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

The extrusion molding device of the present invention will be described below in conjunction with FIG. 1 to FIG. 2 .

As shown in Figures 1 and 2, the extrusion molding device provided in an embodiment of the present invention includes a shell 1 and a core shaft. Specifically, the shell 1 is a cylindrical structure with openings at both ends, the core shaft is arranged inside the shell 1, and an annular gap is formed between the core shaft and the shell 1. After molding, a product with a cylindrical structure can be output, and the discharge speed at each position of the annular gap between the shell 1 and the core shaft is consistent.

The core shaft is relatively fixed to the housing 1 , and a connecting portion is provided at the feed end 17 of the housing 1 for connecting the feed end of the housing 1 with the discharge port of the extrusion device, thereby realizing the connection between the extrusion molding device and the extrusion device.

It should be noted that the feed end 17 of the housing 1 is an end of the housing 1 located at an upstream position along the feed direction, and correspondingly, the other end of the housing 1 is a discharge end 18 of the housing 1. The head end 19 of the mandrel is an end of the mandrel located at an upstream position along the feed direction, and correspondingly, the other end of the mandrel is a tail end 20 of the mandrel.

The distance between the outer wall of the tail end 20 of the core shaft and the inner wall of the shell 1 is less than or equal to the distance between the outer wall of the head end 19 of the core shaft and the inner wall of the shell 1, so as to ensure that the material can be effectively formed between the tail end 20 of the core shaft and the shell 1, thereby ensuring the quality of the processed product.

The material outputted by the extrusion device can enter the annular gap between the shell 1 and the core shaft through the feed end 17 of the shell 1, and can be outputted as a cylindrical structure product after forming. According to specific needs, the cylindrical structure product can also be formed into a flat sheet after later cutting, and the width of the flat sheet product formed by cutting is the circumference of the cylindrical structure product. Under the condition that the output rate of the extrusion device and the thickness of the processed product are constant, the width of the product is increased compared with the flat forming mold in the prior art, and the efficiency and output of extrusion molding are improved.

In the embodiment of the present invention, the core shaft and the housing 1 are coaxially arranged to ensure the consistency of the gap between the core shaft and the housing 1 along the axial direction of the core shaft, ensure that the processed product has a uniform thickness, and improve the quality of the processed product.

Specifically, a connecting bracket can be provided at the head end 19 of the mandrel, and the connecting bracket is connected to the feed end 17 of the shell 1. The connecting bracket can allow the material to pass through the gap between the mandrel and the shell 1. The connecting bracket is fixedly connected to the mandrel, and a conical surface is provided on the inner side wall of the connecting bracket and the shell 1, and the axis of the conical surface, the axis of the mandrel and the axis of the shell 1 coincide. The connecting bracket on the mandrel is in contact with the shell 1 through the conical surface, which is conducive to ensuring the coaxiality between the mandrel and the shell 1, and can improve the assembly accuracy and efficiency.

In the embodiment of the present invention, the connection portion includes a connecting sleeve 13, the first end of which is connected to the discharge port of the extruder. The connecting sleeve 13 is sleeved on the outside of the feed end 17 of the housing 1, and a limiting structure 14 is provided between the second end of the connecting sleeve 13 and the housing 1, for limiting the housing 1 from coming out of the second end of the connecting sleeve 13, and making the axis of the connecting sleeve 13 coincide with the axis of the housing 1.

The above-mentioned limiting structure 14 specifically includes a first limiting step arranged at the second end of the connecting sleeve 13 and a second limiting step arranged on the housing 1. The interaction between the second limiting step and the first limiting step inside the connecting sleeve 13 can limit the housing 1 from coming out of the second end of the connecting sleeve 13. Moreover, the provision of the first limiting step and the second limiting step is also conducive to ensuring the coaxiality between the connecting sleeve 13 and the housing 1.

An internal thread is provided at the first end of the connecting sleeve 13, and correspondingly, an external thread is provided on the discharge port of the extrusion device, and the connecting sleeve 13 and the discharge port of the extrusion device are fixed by threaded connection. The discharge port of the extrusion device extends into the interior of the connecting sleeve 13, and the end of the discharge port of the extrusion device abuts against the end of the housing 1 and the end of the connecting bracket, which can ensure the coaxiality between the discharge port of the extrusion device and the core shaft and the housing 1.

In this embodiment, the mandrel includes a flow guide portion 2 and a forming portion 3, and the flow guide portion 2 is located inside the feed end 17 of the shell 1. The distance between the outer wall of the flow guide portion 2 and the inner wall of the shell 1 is greater than the distance between the outer wall of the forming portion 3 and the inner wall of the shell 1, ensuring that sufficient material enters the feed end 17 of the shell 1.

The guide part 2 is connected to the housing 1 , and the forming part 3 is detachably connected to the guide part 2 . By replacing the forming part 3 with different cross-sectional shapes and sizes, products with different shapes and thicknesses can be processed.

Specifically, an internal thread may be provided on one of the flow guide portion 2 and the forming portion 3 , and an external thread may be provided on the other, so that the flow guide portion 2 and the forming portion 3 are threadedly connected.

In this embodiment, the above-mentioned forming portion 3 includes a first section 5 and a second section 6. The first section 5 is located upstream of the second section 6 along the feeding direction. The first section 5 and the second section 6 form an integrated structure. Specifically, the first section 5 and the second section 6 can be integrally processed and formed, or the first section 5 and the second section 6 can be processed separately and then fixed together by welding or the like. No specific limitation is made here.

The distance between the outer wall of the first section 5 and the inner wall of the shell 1 is greater than the distance between the outer wall of the second section 6 and the inner wall of the shell 1, that is, the cross-sectional area of the flow channel for material flow between the second section 6 and the shell 1 is smaller than the cross-sectional area of the flow channel for material flow between the first section 5 and the shell 1, which can ensure that the material can be effectively formed between the second section 6 and the shell 1, thereby ensuring the quality of the processed product.

The gap h between the outer wall of the second section and the inner wall of the shell can be 0.5-50 mm. In a preferred embodiment, the gap h between the outer wall of the second section and the inner wall of the shell is set to 1-20 mm, which can be specifically determined according to the thickness of the desired processed product. At the same time, the density and compactness of the product is also related to the gap h between the outer wall of the second section and the inner wall of the shell. When the output rate of the extrusion equipment is constant, the smaller the gap h between the outer wall of the second section and the inner wall of the shell, the denser and more compact the processed product. Therefore, in the specific implementation process, the size of the second section 6 of the molding part 3 can also be selected and determined according to the requirements for the density and compactness of the product.

To ensure that the material between the first section 5 and the outer shell 1 can flow smoothly between the second section 6 and the outer shell 1, in this embodiment, a transition slope 7 is provided between the outer wall of the first section 5 and the outer wall of the second section 6, and the first end of the transition slope 7 is connected to the outer wall of the first section 5, and the second end of the transition slope 7 is connected to the outer wall of the second section 6.

The angle α between the transition slope and the axis of the forming portion is 0-60 degrees. In a preferred embodiment, the angle α between the transition slope and the axis of the forming portion is set to 0-45 degrees.

It should be noted that when the outer side surface of the first section 5 is flush with the outer side surface of the second section 6, the angle α between the above-mentioned transition slope and the axis of the forming portion is regarded as 0 degrees. At this time, the above-mentioned transition slope 7 may not be provided, and the outer side surface of the first section 5 is directly connected to the outer side surface of the second section 6.

In the embodiment of the present invention, the tail end 20 of the mandrel can be located inside or outside the housing 1, and the end surface of the tail end 20 of the mandrel can be flush with the end surface of the discharge end 18 of the housing 1. The shapes of the processed products vary depending on the relative positions of the tail end 20 of the mandrel and the discharge end 18 of the housing 1. The relative position between the tail end 20 of the mandrel and the discharge end 18 of the housing 1 can be determined according to specific needs.

The mandrel in the embodiment of the present invention may include only one forming portion 3, or may include multiple forming portions 3. When the mandrel includes one flow guide portion 2 and multiple forming portions 3, any forming portion 3 can be detachably connected to the flow guide portion 2, and the connection structure between each forming portion 3 and the flow guide portion 2 is the same.

The sizes of the second segments 6 of the plurality of molded parts 3 are different, or the cross-sectional shapes of the second segments 6 of the plurality of molded parts 3 are different, or both the sizes and cross-sectional shapes of the second segments 6 of the plurality of molded parts 3 are different. The size of the second segment 6 includes the length size of the second segment 6 and the size of the cross-sectional shape of the second segment 6.

That is, a set of extrusion molding dies in this embodiment includes molding parts 3 of various specifications. By selecting molding parts 3 of different specifications to be connected with the guide part 2, products of different shapes can be processed. It has strong adaptability and can meet various needs of users.

In the embodiment of the present invention, a guide surface 4 is provided on the guide portion 2, and the guide surface 4 is provided on the outer side surface of one end of the guide portion 2 away from the forming portion 3. The distance between the guide surface 4 and the axis of the guide portion 2 gradually increases in the direction close to the forming portion 3, so that the guide portion 2 has a conical structure. The space between the guide portion 2 and the shell 1 gradually decreases, which can ensure that more materials enter the feed end 17 of the shell 1, and ensure that the materials can smoothly enter between the guide portion 2 and the shell 1 and flow between the forming portion 3 and the shell 1, avoiding the problem of material accumulation at the head end 19 of the core shaft.

In this embodiment, the angle between the guide surface 4 and the axis of the guide portion 2 is 15-60 degrees, and accordingly, the cone angle of the guide portion 2 is 30-120 degrees. In a specific embodiment, the angle between the guide surface 4 and the axis of the guide portion 2 can be set to 30 degrees, so that the cone angle of the guide portion 2 is 60 degrees, and when processing high-viscosity materials, it is ensured that the high-viscosity materials can smoothly and evenly enter between the core shaft and the housing 1.

In an embodiment of the present invention, the extrusion molding device further includes a temperature control component, which is used to control the temperature of the outer shell 1 and/or the temperature of the core shaft. The outer shell 1 and the core shaft are in direct contact with the material, and the temperature of the material can be adjusted by adjusting the temperature of the outer shell 1 and/or the core shaft, and by utilizing the heat exchange between the outer shell 1 and the core shaft and the material respectively. For example, in the processing of "plant meat", cooling is required while molding. The temperature difference between the core shaft and the outer shell 1 is different, and the internal and external morphology of the resulting product will also change.

Only the temperature of the shell 1 may be regulated, or only the temperature of the core shaft may be regulated, or both the temperature of the shell 1 and the temperature of the core shaft may be regulated at the same time, and the specific temperature may be determined according to actual conditions.

The temperature control assembly includes a first heat exchange part 8 and/or a second heat exchange part. The first heat exchange part 8 has a first heat exchange channel 9 for the circulation of a heat exchange medium. The first heat exchange part 8 is sleeved on the outside of the shell 1. The temperature of the shell 1 can be regulated by heat exchange between the heat exchange medium and the shell 1. The second heat exchange part has a second heat exchange channel 16 for the circulation of a heat exchange medium. The second heat exchange part is arranged inside the core shaft. The temperature of the core shaft can be regulated by heat exchange between the heat exchange medium and the core shaft.

The first heat exchange part 8 and the second heat exchange part are both provided with a medium inlet 10 and a medium outlet 11 for the heat exchange medium to enter and exit. The medium inlet 10 is provided on the lower side wall of the first heat exchange part 8 and the second heat exchange part, and the medium outlet 11 is provided on the upper side wall of the first heat exchange part 8 and the second heat exchange part, which can avoid the gas blockage problem caused by gas residue in the first heat exchange part 8 and the second heat exchange part, and ensure the temperature uniformity of the shell 1 and the core shaft.

Since the mandrel is located inside the housing 1 and the second heat exchange part is arranged inside the mandrel, when the second heat exchange part is arranged, it is necessary to avoid arranging the medium inlet 10 and the medium outlet 11 of the second heat exchange part on the second section 6 of the forming part 3 to avoid affecting the forming effect. Specifically, the medium inlet 10 and the medium outlet 11 can be arranged on the first end of the forming part 3 or the guide part 2.

When it is necessary to regulate the temperature of the outer shell 1 and the temperature of the core shaft at the same time, the first heat exchange part 8 and the second heat exchange part can be set at the same time; when only the temperature of the outer shell 1 needs to be regulated, only the first heat exchange part 8 can be operated or only the first heat exchange part 8 can be set; when only the temperature of the core shaft needs to be regulated, only the second heat exchange part can be operated or only the second heat exchange part can be set.

The above-mentioned first heat exchange part 8 can be fixed on the outside of the outer shell 1. Specifically, the first heat exchange part 8 can be set in the form of a jacket and fixed on the outside of the outer shell 1; a sleeve can also be set on the outside of the outer shell 1, so that the two ends of the sleeve are sealed and connected to the outer shell 1; a cavity can also be set on the side wall of the outer shell 1 for the heat exchange medium to flow, so that the first heat exchange part 8 and the outer shell 1 form an integrated structure.

In an optional embodiment, the first heat exchange part 8 is slidably sleeved on the outer shell 1. During the product processing, the relative position between the first heat exchange part 8 and the outer shell 1 can be adjusted according to specific needs. Specifically, the first heat exchange part 8 can be set in the form of a sealing jacket, so that the sealing jacket is slidably connected to the outer shell 1; a sleeve can also be set outside the outer shell 1, and a sealing member 15 is set between the two ends of the sleeve and the outer shell 1. The sealing member 15 here can be a material with good sealing performance such as a skeleton oil seal to ensure a movable seal between the sleeve and the outer shell 1.

The second heat exchange part is arranged inside the core shaft. Specifically, the core shaft can be processed into a hollow structure, and the internal cavity of the core shaft can be used as the second heat exchange channel 16.

The first heat exchange channel 9 and the second heat exchange channel 16 may extend along a straight line or a curve.

When the first heat exchange channel 9 and the second heat exchange channel 16 extend along a curve, the first heat exchange channel 9 and the second heat exchange channel 16 can be arranged in a spiral shape, so as to increase the circulation time of the heat exchange medium in the first heat exchange channel 9 and the second heat exchange channel 16 and ensure the heat exchange effect.

In the embodiment of the present invention, the extrusion molding device further includes a diverter plate 12, and a through hole for the material to pass through is provided on the diverter plate 12. The diverter plate 12 can be arranged between the guide portion 2 and the housing 1 or between the first section 5 and the housing 1. The diverter plate 12 has the function of evenly diverting the material and changing the internal structure of the material.

The through hole on the diverter plate 12 can be an annular gap coaxially arranged with the core shaft, or a plurality of circular holes. When the through hole of the diverter plate 12 installed between the guide part 2 and the housing 1 has different shapes, the material will present different internal structures and arrangement forms after passing through different diverter plates 12, and the processed products will have different internal structures, and accordingly, the taste of the products will also be different.

In summary, the extrusion molding device in the embodiment of the present invention can process products with a cylindrical structure, and the product form is novel, and solves the problem that the extrusion molding die in the prior art can only process flat sheet products, and the discharge speed of each position of the annular gap between the shell 1 and the core shaft is consistent. In addition, according to specific needs, the product with a cylindrical structure can also be cut into a flat sheet after a later stage, and the width of the flat sheet product formed by cutting is the circumference of the cylindrical structure product, which increases the width of the flat sheet product, and improves the molding efficiency and output of the extrusion mold when the output rate of the extrusion equipment and the thickness of the processed product are constant.

Products with different shapes and structures can be manufactured by changing the cross-sectional size and length of the forming portion 3 of the core shaft, the angle between the transition slope 7 and the axis of the forming portion 3, the relative position between the first heat exchange portion 8 and the shell 1, etc.

In general, the extrusion molding device in the embodiment of the present invention has the advantages of flexible combination, easy use, diverse product types, flexible and adjustable product structure and characteristics, and significantly improved output.

On the other hand, an embodiment of the present invention further provides an extruder, including the extrusion molding device provided by any of the above embodiments, which has all the advantages of the above extrusion molding device. The derivation process of the beneficial effects of the extruder in the embodiment of the present invention is generally similar to the derivation process of the beneficial effects of the above extrusion molding device, so it will not be repeated here.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (14)

1. An extrusion molding device, characterized in that it comprises: The outer shell is a cylindrical structure with openings at both ends, and the feed end of the outer shell is provided with a connecting portion for connecting with the discharge port of the extrusion device; A core shaft is arranged inside the shell and forms an annular gap with the shell, the core shaft is relatively fixed to the shell, the distance between the outer wall of the tail end of the core shaft and the inner wall of the shell is less than or equal to the distance between the outer wall of the head end of the core shaft and the inner wall of the shell, the core shaft includes a guide part and multiple forming parts, the guide part is arranged inside the feed end of the shell, the guide part is connected to the shell, any of the forming parts can be detachably connected to the guide part, the forming part includes a first section and a second section, the first section is located upstream of the second section along the feed direction, the first section and the second section form an integrated structure, the size of the second section at least includes the length size of the second section, and the sizes of the second sections of the multiple forming parts are different, so that the tail end of the core shaft is located inside the shell, or the end face of the tail end of the core shaft is flush with the end face of the discharge end of the shell, or the tail end of the core shaft is located outside the shell. 2 . The extrusion molding device according to claim 1 , wherein the axis of the core shaft coincides with the axis of the shell. 3. The extrusion molding device according to claim 1 or 2 is characterized in that a guide surface is provided on the outer side surface of one end of the guide portion away from the molding portion, and the distance between the guide surface and the axis of the guide portion gradually increases in a direction approaching the molding portion. 4 . The extrusion molding device according to claim 3 , characterized in that the angle between the guide surface and the axis of the guide portion is 15-60 degrees. 5 . The extrusion molding device according to claim 1 , wherein the distance between the outer side wall of the first section and the inner side wall of the shell is greater than the distance between the outer side wall of the second section and the inner side wall of the shell. 6 . The extrusion molding device according to claim 5 , wherein the cross-sectional shapes of the second sections of the plurality of molding parts are different, and the size of the second section also includes the cross-sectional size of the second section. 7. The extrusion molding device according to claim 1 is characterized in that a transition slope is provided between the outer side wall of the first section and the outer side wall of the second section, and the angle between the transition slope and the axis of the molding part is 0-60 degrees. 8. The extrusion molding device according to claim 1, characterized in that it also includes: A temperature control component is used to control the temperature of the shell and/or the temperature of the core shaft. 9. The extrusion molding device according to claim 8, characterized in that the temperature control component comprises: A first heat exchange part having a first heat exchange channel for heat exchange medium to flow, wherein the first heat exchange part is sleeved on the outside of the shell; and/or, a second heat exchange portion having a second heat exchange channel for heat exchange medium to flow through, the second heat exchange portion being arranged inside the core shaft; The first heat exchange part and the second heat exchange part are both provided with a medium inlet and a medium outlet for heat exchange medium to enter and exit. 10 . The extrusion molding device according to claim 9 , wherein the first heat exchange portion is movably disposed on the outer shell, or the first heat exchange portion and the outer shell form an integrated structure. 11. The extrusion molding device according to claim 9, characterized in that the first heat exchange channel and the second heat exchange channel extend along a straight line; Alternatively, the first heat exchange channel and the second heat exchange channel extend along a curve. 12. The extrusion molding device according to claim 5, characterized in that it also includes: The flow dividing plate has a through hole for materials to pass through, and the flow dividing plate is arranged between the guide part and the shell or between the first section and the shell. 13. The extrusion molding device according to claim 1 is characterized in that the connecting part includes a connecting sleeve whose first end can be connected to the discharge port of the extrusion equipment, the connecting sleeve is sleeved on the outside of the feed end of the outer shell, and a limiting structure is arranged between the second end of the connecting sleeve and the outer shell, and the limiting structure is used to limit the outer shell from escaping from the second end of the connecting sleeve and to make the axis of the connecting sleeve coincide with the axis of the outer shell. 14. An extruder, characterized in that it comprises the extrusion molding device according to any one of claims 1 to 13.