Solid-phase additive twin-screw extrusion structure

Abstract

The utility model belongs to the technical field of solid-phase friction extrusion additive materials, and particularly relates to a solid-phase additive material double-screw extrusion structure. The screw rod comprises a first screw rod and a second screw rod which are applied to a feeding unit of the solid-phase additive material equipment, the first screw rod and the second screw rod are oppositely arranged, the rotating directions of the first screw rod and the second screw rod are opposite, and each of the first screw rod and the second screw rod comprises a first screw rod section and a second screw rod section which are arranged in the additive material conveying direction; the screw pitch of the first screw section is larger than that of the second screw section. The thread direction of the first screw is opposite to the thread direction of the second screw. According to the utility model, the double-screw structure is adopted, and compared with a single-screw structure, the extrusion force of the double screws is far greater than that of the single screw, so that the extrusion efficiency is improved; and in the process of extruding the additive raw materials through the double screws, the additive raw materials can be subjected to pre-plasticizing treatment.

Description

Technical Field

[0001] The utility model belongs to the technical field of solid-phase friction extrusion material addition, and in particular relates to a solid-phase material addition twin-screw extrusion structure. Background Art

[0002] The solid phase friction extrusion additive manufacturing process is currently the most advanced metal additive manufacturing technology. Since it can effectively avoid additive defects such as melt-solidification porosity, unfused materials and thermal cracks, this metal additive technology has become the most effective process method for obtaining fully dense and high-performance lightweight alloys. It has huge application potential in the field of lightweight aluminum-magnesium alloy structure manufacturing.

[0003] like Figure 3 As shown, the existing solid-phase friction extrusion additive manufacturing equipment mainly uses single-screw extrusion. Although single-screw extrusion molding can achieve continuous extrusion, it is easy to have insufficient extrusion force during extrusion of materials with high viscosity, resulting in blockage of the additive raw materials; in addition, single-screw extrusion can only play a transfer role and cannot pre-plasticize the additive raw materials, resulting in low additive efficiency.

[0004] Therefore, there is an urgent need for a solid-phase additive twin-screw extrusion structure to solve the above problems. Utility Model Content

[0005] In order to overcome the defects in the prior art, the utility model provides a solid-phase additive twin-screw extrusion structure. The utility model can not only increase the extrusion force, but also pre-plasticize the additive raw materials.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A solid-phase additive twin-screw extrusion structure comprises a first screw and a second screw applied to a feeding unit of a solid-phase additive device, wherein the first screw and the second screw are arranged opposite to each other and rotate in opposite directions, and the first screw and the second screw both comprise a screw segment 1 and a screw segment 2 arranged along a direction in which additive raw materials are transmitted, the pitch of the screw segment 1 is greater than the pitch of the screw segment 2; and the thread direction of the first screw and the thread direction of the second screw are arranged in opposite directions.

[0008] Preferably, the first screw and the second screw are both in a conical structure, and the diameter of the first screw segment is greater than the diameter of the second screw segment.

[0009] Preferably, the thread of the second screw segment is a texture structure composed of a plurality of groups of cross pieces arranged in sequence along the thread direction, and the cross pieces are in an "X" shape.

[0010] Preferably, the thread width of screw segment one is greater than the thread width of screw segment two.

[0011] Preferably, the first screw and the second screw are arranged at an angle of 0-15 degrees, and the distance between two screw segments 1 is smaller than the distance between two screw segments 2.

[0012] Preferably, the first screw and the second screw are connected by a driving device, and the rotation speed of the first screw is the same as the rotation speed of the second screw.

[0013] Preferably, the first screw and the second screw are both transmission-connected to the same motor via a conversion structure.

[0014] Preferably, the first screw and the second screw are transmission-connected to two motors respectively.

[0015] The advantages of the utility model are:

[0016] (1) The utility model adopts a twin-screw structure. Compared with a single-screw structure, the extrusion force of the twin-screw is much greater than that of the single-screw, thereby improving the extrusion efficiency and effectively avoiding blockage caused by insufficient extrusion force. The twin-screw can also pre-plasticize the additive raw material during the extrusion of the additive raw material, thereby increasing the temperature of the additive raw material before addition and improving the additive efficiency.

[0017] (2) The twin-screw extruder structure of the utility model adopts a tapered structure with a thick upper section and a thin lower section. During the process of transmitting the additive raw material from the upper end to the lower end, the additive raw material is subjected to spiral extrusion and shearing, so that the additive raw material is pre-plasticized before reaching the discharge port, thereby improving the degree of plastic softening of the additive raw material before extrusion and further improving the additive efficiency.

[0018] (3) The lower section of the screw of the utility model is a double-thread structure, which can not only ensure the extrusion transmission function, but also play a stirring role, making it easier to break up the additive raw materials, making the mixing more uniform, and improving the additive quality.

[0019] (4) In the utility model, the pitch of the upper section of the screw is greater than the pitch of the lower section of the screw, and the thread width of the upper section of the screw is greater than the thread width of the lower section of the screw, so that the closer the additive raw material is to the discharge port, the more stable the transmission is, which can further improve the additive quality of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of Example 1 of the utility model.

[0021] Figure 2 This is a schematic diagram of the structure of Example 2 of the utility model.

[0022] Figure 3 It is a schematic diagram of the single screw structure in the solid phase friction extrusion additive manufacturing equipment in the prior art.

[0023] The meanings of the symbols in the figure are as follows:

[0024] 1-first screw, 2-second screw, 3-screw segment one, 4-screw segment two. DETAILED DESCRIPTION

[0025] A solid-phase additive twin-screw extrusion structure, which is used in solid-phase additive equipment. The additive raw materials are aluminum-magnesium alloy particles (powder) or aluminum wire, magnesium wire, etc., and are used to extrude the additive raw materials entering the equipment to the discharge port. The extrusion structure adopts a twin-screw structure to replace the previous single screw, and is driven by a driving device (motor). Specifically, it can be driven by one motor or two motors.

[0026] The screw segment 1 3 of the first screw 1 and the screw segment 1 3 of the second screw 2 are both upper segments of the screw; the screw segment 2 4 of the first screw 1 and the screw segment 2 4 of the second screw 2 are both lower segments of the screw.

[0027] Example 1

[0028] like Figure 1 As shown, the first screw 1 and the second screw 2 have opposite thread directions, and the two screws rotate relative to each other under the drive of the motor (equivalent to meshing transmission), thereby realizing the transmission of additive raw materials. The twin-screw extrusion structure is a conical structure with a thick upper section and a thin lower section, and the first screw 1 and the second screw 2 are set at an angle of 0-15 degrees. During the process of transmitting the additive raw material from the upper end to the lower end, the additive raw material is subjected to spiral extrusion and shearing, so that the raw material is pre-plasticized before reaching the discharge port, thereby improving the plastic softening degree of the additive raw material before extrusion, and facilitating the improvement of additive efficiency.

[0029] Furthermore, the pitch of the upper section of the screw is designed to be greater than the pitch of the lower section, and the thread width of the upper section of the screw is designed to be greater than the thread width of the lower section, so that the closer the additive raw material is to the discharge port, the more stable the transmission is, which can further improve the additive quality of the product.

[0030] Example 2

[0031] like Figure 2 As shown, the screw segment 2 4 of the first screw 1 and the screw segment 2 4 of the second screw 2 are both the lower segments of the screws, and have a double thread structure, that is, the screw segment 2 4 is provided with a plurality of groups of cross pieces in an "X"-shaped structure, and the cross pieces are arranged in sequence along the thread direction to form a pattern. This structure not only has the function of extrusion transmission, but also is similar to a stirring blade, which can play a better stirring role, so that the additive raw materials are evenly mixed after being broken up, thereby improving the quality of the additive.

[0032] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A solid phase additive twin-screw extrusion structure, characterized in that: The invention comprises a first screw (1) and a second screw (2) applied to a feeding unit of a solid-phase additive device, wherein the first screw (1) and the second screw (2) are arranged opposite to each other and rotate in opposite directions, and the first screw (1) and the second screw (2) both comprise a screw segment 1 (3) and a screw segment 2 (4) arranged along the direction of transmission of the additive raw material, and the pitch of the screw segment 1 (3) is greater than the pitch of the screw segment 2 (4); and the thread direction of the first screw (1) and the thread direction of the second screw (2) are arranged in opposite directions.

2. A solid phase additive twin-screw extruder structure according to claim 1, characterized in that: The first screw (1) and the second screw (2) are both conical structures, and the diameter of the first screw segment (3) is greater than the diameter of the second screw segment (4).

3. A solid phase additive twin-screw extruder structure according to claim 1, characterized in that: The thread of the second screw segment (4) is a texture structure composed of a plurality of groups of cross pieces arranged in sequence along the thread direction, and the cross pieces are in an "X" shape.

4. The solid phase additive twin-screw extruder structure according to claim 1, characterized in that: The thread width of the screw segment one (3) is greater than the thread width of the screw segment two (4).

5. The solid phase additive twin-screw extruder structure according to claim 1, characterized in that: The first screw (1) and the second screw (2) are arranged at an angle of 0-15 degrees, and the distance between the two screw segments (3) is smaller than the distance between the two screw segments (4).

6. The solid phase additive twin-screw extrusion structure according to claim 1, characterized in that: The first screw (1) and the second screw (2) are connected by a driving device, and the rotation speed of the first screw (1) is the same as the rotation speed of the second screw (2).

7. A solid phase additive twin-screw extruder structure according to claim 6, characterized in that: The first screw (1) and the second screw (2) are both transmission-connected to the same motor via a conversion structure.

8. The solid phase additive twin-screw extrusion structure according to claim 6, characterized in that: The first screw (1) and the second screw (2) are respectively connected to two motors in a transmission manner.

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