A cross-modulus material gradient printing feed system

Abstract

This invention discloses a gradient printing feeding system for cross-modulus materials. An ultrasonic oscillator is fixed outside a mixing tank. The mixing tank is connected to a gradient feeding system, which in turn is connected to a screw extrusion system. The gradient feeding system includes discharge pipes, liquid pipes, one-way valves, and a multi-port connector. Multiple discharge pipes are sequentially opened along the vertical height of the mixing tank, with each discharge pipe's opening height corresponding to one of the layered materials. Each discharge pipe is connected to a liquid pipe, and each liquid pipe is equipped with a one-way valve. The multi-port connector is installed on the upper side of the screw extrusion system and is connected to all the liquid pipes, used to feed the material in the liquid pipes into the screw extrusion system. This invention eliminates the need to stop the printing process to change materials during the entire printing process. Material switching during printing is achieved through gradient feeding, resulting in a short working cycle and high efficiency.

Description

Technical Field

[0001] This invention belongs to the field of extrusion bio-3D printing, specifically relating to a gradient printing feeding system for transmodulus materials. Background Technology

[0002] With the gradual maturation of 3D printing technology, various printing devices for biomedical applications have emerged in recent years. These include 3D printing equipment based on principles such as fused deposition modeling, extrusion, photopolymerization, and laser sintering, using metals, alloys, ceramics, plastics, and hydrogels as printing inks. These devices are applied to bone implants, dental implants, bone guides, and medical teaching instruments. For example, when using inorganic materials as printing inks to construct biomimetic bone structures, the conventional approach for printing structures with different density requirements, such as cortical bone and cancellous bone, is to use multiple nozzles to print multiple sets of inks. This requires switching nozzles to achieve gradient printing of materials with different particle sizes across moduli, and also necessitates separately screening bone powders of various particle sizes and preparing individual inks. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention proposes a gradient printing feeding system for transmodulus materials, which solves the problem of continuous gradient printing of transmodulus materials in existing extrusion bio-3D printing technology. It completely abandons the existing multi-nozzle transmodulus material gradient printing method and achieves rapid gradient distribution printing with controllable particle size.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] A gradient printing feeding system for transmodulus materials includes a mixing tank, a material pool, a screw feeding system, a gradient feeding system, a screw extrusion system, an extruder head, and an ultrasonic oscillator.

[0006] The mixing tank has a feed inlet on one side of its top, and a material pool is fixedly connected to the feed inlet of the mixing tank. The material pool is used to contain transmodulus material. The piston rod of the screw feeding system extends into the material pool to push the transmodulus material in the material pool into the mixing tank. The ultrasonic vibrator is fixed to the outside of the mixing tank. The mixing tank is connected to the gradient feeding system, and the gradient feeding system is connected to the screw extrusion system. The extrusion head is located in the screw extrusion system.

[0007] The gradient feeding system includes a discharge pipe, a liquid pipeline, a one-way valve, and a multi-port connector. Multiple discharge pipes are sequentially opened along the vertical height of the mixing tank, with the opening height of each discharge pipe corresponding to one of the layered materials. Each discharge pipe is connected to a liquid pipeline, and each liquid pipeline is equipped with a one-way valve. The multi-port connector is installed on the upper side of the screw extrusion system and is connected to all the liquid pipelines, used to feed the material in the liquid pipelines into the screw extrusion system.

[0008] Furthermore, a one-way valve is provided at the bottom of the material pool to control the material to flow from the material pool into the mixing tank in one direction.

[0009] Furthermore, the top of the mixing barrel is provided with an air hole to balance the air pressure inside the mixing barrel.

[0010] Furthermore, the gradient feeding system has at least one discharge pipe.

[0011] Furthermore, the extrusion head is fixed on the three-axis motion mechanism, and the other parts of the transmodulus material gradient printing feeding system are all fixed on the extrusion printer frame.

[0012] The beneficial effects of this invention are as follows:

[0013] The transmodulus material gradient printing feeding system of this invention utilizes the static stratification characteristic of transmodulus materials. By simply agitating a mixing tank containing bone powder of various particle sizes using an ultrasonic oscillator, the material automatically stratifies. Then, bone powder of different particle sizes is fed into the extrusion head through liquid pipes connecting the different layers, thus forming a transmodulus material gradient structure. Compared to conventional extrusion printing, it is suitable for integrated printing of multiple materials using the same nozzle, greatly improving the efficiency of multi-material extrusion printing. Compared to conventional printing methods that require switching between the feed tank or extrusion head, this invention eliminates the need to stop the printing process to change materials. Material switching during printing is achieved through gradient feeding, especially for transmodulus materials such as bone powder + hydrogel, resulting in a short working cycle, high efficiency, and low cost. Attached Figure Description

[0014] Figure 1 This is a gradient printing feeding system for transmodulus materials according to an embodiment of the present invention.

[0015] Figure 2 This is a schematic diagram of the gradient feeding system 4. Detailed Implementation

[0016] The present invention will be described in detail below with reference to the accompanying drawings and preferred embodiments. The purpose and effects of the present invention will become clearer. It should be understood that the specific embodiments described herein are merely for explaining the present invention and are not intended to limit the present invention.

[0017] like Figure 1 As shown, the gradient printing feeding system for transmodulus materials in this embodiment includes a mixing tank 1, a material pool 2, a screw feeding system 3, a gradient feeding system 4, a screw extrusion system 5, an extruder head 6, and an ultrasonic vibrator 8. The material pool 2 is fixedly installed at the inlet on one side of the top of the mixing tank 1. The material pool 2 is used to contain transmodulus materials, and a one-way valve is installed at the bottom of the material pool 2 to control the unidirectional flow of material from the material pool 2 into the mixing tank 1.

[0018] The piston rod of the screw feeding system 3 extends into the material pool 2 to push the transmodulus material in the material pool 2 into the mixing tank 1. An air vent 7 is also provided at the top of the mixing tank 1 to balance the air pressure inside. An ultrasonic vibrator 8 is fixed to the outside of the mixing tank 1 to provide vibration drive for the transmodulus material in the mixing tank 1. The mixing tank 1 is connected to the gradient feeding system 4, which is connected to the screw extrusion system 5. The extruder head 6 is located within the screw extrusion system 5.

[0019] Among them, such as Figure 2 As shown, the gradient feeding system 4 includes a discharge pipe 401, a liquid pipeline 402, a one-way valve 403, and a multi-port connector 404. Multiple discharge pipes 401 are sequentially opened along the vertical height of the mixing tank 1, with the opening height of each discharge pipe 401 corresponding to one of the layered materials. Each discharge pipe 401 is connected to a liquid pipeline 402, and each liquid pipeline 402 is equipped with a one-way valve 403. The multi-port connector 404 is installed on the upper side of the screw extrusion system 5 and is connected to all the liquid pipelines 402, used to feed the material in the liquid pipelines 402 into the screw extrusion system 5. By real-time switching of the one-way valve 403, ink is drawn from different vertical heights of the mixing tank 1 into the extruder head 6, and then extruded into shape by the screw extrusion system 5.

[0020] The transmodulus material gradient printing feeding system of this embodiment is mounted on an extruder frame. The extruder frame mainly consists of a frame and a conventional three-axis motion mechanism, including but not limited to a Cartesian coordinate system motion mechanism. It can be stably placed on the ground or platform surface by fixed feet. Except for the extrusion head 6, which is mounted on the three-axis motion mechanism, all other components are fixed on the frame of the extruder frame.

[0021] This embodiment uses bone powder hydrogel as an example, and describes the working principle of the transmodulus material gradient printing feeding system of this embodiment with a gradient feeding system 4 having 5 discharge pipes 401. There is no need for manual separation of bone powder of different particle sizes. After mixing the bone powder hydrogel, it is placed in the material tank 2. The screw feeding system 3 drives the pusher to push the material in the material tank 2 into the mixing tank 3. The ultrasonic oscillator 8 is activated, and bone powder of different particle sizes separates into layers in the mixing tank 1 after ultrasonic vibration. The five one-way valves 403 of the gradient feeding system 4 are opened and closed as needed, and the screw extrusion system 5 is activated. As the screw extrusion system 5 rotates, a negative pressure is generated at the discharge port of the one-way valve 403, drawing out the bone powder hydrogel material from the opened valve and into the extruder head 6. As the screw extrusion system 5 rotates, the material is pushed out to the tip of the extruder head 6, forming extruded filaments. By switching the five one-way valves 403 of the gradient feeding system 4, hydrogel ink containing bone powder of different particle sizes can be fed in and out to form a transmodulus material gradient structure.

[0022] The transmodulus material gradient printing feeding system of the present invention can realize the free and high-precision distribution of various materials in space according to the designed structure, support the continuous printing of materials with large modulus span, especially the on-demand mixing and printing of low modulus hydrogels and high modulus bone powder, and support the three-dimensional spatial density gradient distribution of heterogeneous multi-particle-size bone powder. It can achieve automatic, fast and particle size controllable gradient distribution printing.

[0023] It will be understood by those skilled in the art that the above descriptions are merely preferred examples of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions described in the foregoing examples or make equivalent substitutions for some of the technical features. All modifications and equivalent substitutions made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A gradient printing feeding system for transmodulus materials, characterized in that, It includes a mixing tank (1), a material pool (2), a screw feeding system (3), a gradient feeding system (4), a screw extrusion system (5), an extruder (6), and an ultrasonic vibrator (8); The mixing tank (1) has a feed inlet on one side of its top. The material pool (2) is fixed to the feed inlet of the mixing tank (1) and is used to contain transmodulus material. The piston rod of the screw feeding system (3) extends into the material pool (2) and is used to push the transmodulus material in the material pool (2) into the mixing tank (1). The ultrasonic oscillator (8) is fixed outside the mixing tank (1). The mixing tank (1) is connected to the gradient feeding system (4), and the gradient feeding system (4) is connected to the screw extrusion system (5). The extrusion head (6) is located in the screw extrusion system (5). The gradient feeding system (4) includes a discharge pipe (401), a liquid pipe (402), a one-way valve (403), and a multi-port connector (404); multiple discharge pipes (401) are opened sequentially along the vertical height of the mixing tank (1), and the opening height of each discharge pipe (401) corresponds to one of the layered materials; each discharge pipe (401) is connected to a liquid pipe (402), and a one-way valve (403) is provided on each liquid pipe (402); the multi-port connector (404) is installed on the side above the screw extrusion system (5), and the multi-port connector (404) is connected to all the liquid pipes (402) for feeding the material in the liquid pipes (402) into the screw extrusion system (5).

2. The gradient printing feeding system for transmodulus materials according to claim 1, characterized in that, A one-way valve is provided at the bottom of the material pool (2) to control the material to flow from the material pool (2) into the mixing tank (1) in one direction.

3. The gradient printing feeding system for transmodulus materials according to claim 1, characterized in that, The top of the mixing tank (1) is also provided with an air hole (7) to balance the air pressure inside the mixing tank (1).

4. The gradient printing feeding system for transmodulus materials according to claim 1, characterized in that, The gradient feeding system (4) has no fewer than three discharge pipes (401).

5. The gradient printing feeding system for transmodulus materials according to claim 1, characterized in that, The extrusion head (6) is fixed on the three-axis motion mechanism, and the other parts of the transmodulus material gradient printing feeding system are fixed on the extrusion printer frame.

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