CN108312497B - Unsupported 3D suspension printing structure and method - Google Patents

Abstract

The invention discloses an unsupported 3D suspension printing structure and method, comprising: adopting an ultrasonic suspension method, placing the part in a sound field during the 3D printing process of the part, and supporting the suspended or floating part under the action of ultrasonic radiation force; Ensure that the initial layers of materials are printed to support the printing of subsequent layers, and then complete the 3D printing of parts without support. On the one hand, the present invention greatly reduces the cost of the support material, greatly improves the manufacturing efficiency, and on the other hand, the influence on the product quality that may be caused by the unfavorable support is eliminated. Especially for thin-shell parts, some support materials even account for more than 60% of the overall material consumption. If the part is printed without support, the cost is expected to be saved by more than 50%, and the manufacturing cycle will be shortened by more than 40%. And don't have to worry about the quality issues that support removal may cause.

Description

An unsupported 3D suspension printing structure and method

technical field

The invention belongs to the technical field of 3D printing, and particularly relates to an unsupported 3D suspension printing structure and method.

Background technique

The principle of 3D printing technology requires that the upper structure of the model must be supported by the lower part. Therefore, if some parts of the printed model are suspended or floating, a support structure needs to be designed during printing. When FDM is used for printing, its working principle is to heat the material to a semi-fluid state and extrude it on the printing plate in a layer-by-layer stack. Although it solidifies quickly, it is affected by gravity during the printing process. Influence, when the angle α between a certain surface of the model and the vertical line is greater than 45° and is suspended in the air, the material will fall before solidification. This is the 45° angle principle in 3D printing, that is, if the α is too large, a support structure needs to be added. In addition, if the model has a floating structure, space islands will be formed when slicing and printing. At this time, adding supports is the only option.

Less and no support is one of the hot spots in 3D printing research, but the "unsupported" mentioned at present has not yet achieved true unsupported, and still belongs to the category of process structure optimization, which mainly includes transferring the support position, disassembling and printing the model and then assembling it. Maximum printable overhang angle optimization. The current "unsupported" printing method, although the concept of "unsupported" is mentioned, has a limited scope of application, and does not really realize unsupported printing, which is still a process structure improvement with less support. In order to achieve true unsupported printing, it is necessary to break through the existing 3D printing support research framework, consider the intersection of disciplines, and achieve innovation in principles and methods.

Ultrasonic levitation uses a high-intensity sound field to generate sound radiation pressure, which is balanced with the gravity of the suspended object, so that the object placed in the sound field is suspended. This technology is different from technologies such as magnetic levitation, superconducting levitation, and pneumatic levitation, which can suspend any substance, including liquids and solids. A typical standing wave device (often called a uniaxial) consists of a circular transducer and a reflector, which are arranged coaxially and separated by a certain distance, when the distance between the transmitting end and the reflecting end of the ultrasonic wave is When the ultrasonic wave is an integer multiple of the half wavelength, the ultrasonic wave will be repeatedly superimposed between the transmitting end and the reflecting end, thereby establishing a high-voltage amplitude standing wave between the transmitter and the reflector, and the formed high-intensity standing wave will pass through the medium. Radiated sound pressure acts on the sample in the standing wave field, which causes the sample to levitate. At present, ultrasonic standing wave suspension has no special requirements on the physical and chemical properties of the suspended objects, and is mainly used for the study of single particles or small droplets, which can avoid the loss of analytes caused by the uncertain adsorption, memory effect and pollution of the container wall.

The existence of 3D printing supports, on the one hand, increases the cost and inefficiency of manufacturing, and on the other hand may cause the removal of supports to adversely affect product quality. Some complex curved thin shell parts models are printed as a whole, and the support material even accounts for more than 60% of the overall material consumption. If the part is printed without support, according to the Cura analysis results, the cost is expected to be saved by more than 50%. Cycle times are around 40% shorter, and you don't have to worry about quality issues that support removal can cause.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an unsupported 3D suspension printing structure and method, which can realize unsupported printing of various 3D printing technologies, save costs, improve manufacturing efficiency, and thus facilitate the low-cost application and promotion of 3D printing.

The present invention adopts the following technical scheme to realize:

An unsupported 3D suspension printing structure includes an ultrasonic phase array bracket, a buzzer array arranged on both sides of the ultrasonic phase array bracket, an ultrasonic transmitting power source and a control mechanism connected with the buzzer array, and an ultrasonic phase array bracket arranged on the ultrasonic phase array bracket. In the upper 3D printing head, two sets of buzzer arrays respectively form the transmitting end and reflecting end of the suspended sound field.

A further improvement of the present invention is that each group of buzzer arrays includes dozens to hundreds of buzzers.

An unsupported 3D suspension printing method, comprising the following steps:

1) Design the suspended sound field according to the situation of 3D printing equipment;

2) Adjust the process parameters of the nozzle diameter, temperature and wire feeding speed of the print head;

3) Combine the constructed suspended sound field with the existing 3D printing equipment;

4) The suspended sound field is composed of a buzzer array, and the ultrasonic frequency and amplitude are adjusted until there are more nodes, so that the nodes can support the continuous filament, and the printing material can form a stable floating point in the 3D printing equipment;

5) Overall control of the coordination relationship between the suspension point and the printing filament, to realize the coupled printing between each other.

A further improvement of the present invention is that, in step 1), the 3D printing device is an FDM printer, or a jet printing device.

A further improvement of the present invention is that the printing material of the FDM printer is a thermoplastic material.

A further improvement of the present invention is that, in step 1), the suspension sound field is a standing wave suspension sound field.

A further improvement of the present invention is that, in step 2), the diameter of the nozzle of the print head is 0.4 mm or 0.8 mm.

A further improvement of the present invention is that, in step 5), the coupling relationship refers to the coupling between the thermal field and the sound field.

The present invention has the following advantages:

The present invention uses ultrasonic suspension technology in 3D printing technology to realize unsupported printing of products. Compared with the existing 3D printing method, using the structure and method of the present invention has the following advantages:

1. The unsupported printing method of the present invention can realize suspended printing of products without support, reduce the consumption of 3D printing materials, especially for thin shell parts, which is of great significance and can greatly improve the printing efficiency;

2. Unsupported suspension printing eliminates the need to consider the removal of support materials, thereby ensuring the surface quality of the product;

3. The application of the present invention will effectively promote the reduction of the overall cost of 3D printing, and effectively expand its application field and scope.

4. 3D printing equipment is continuous wire printing equipment such as FDM printers, and can also be used for printing equipment such as jet printing and other printing equipment that outputs materials from the print head. It can be used not only for non-metallic material printing equipment, but also for metal material printing equipment.

To sum up, on the one hand, the present invention greatly reduces the cost of support materials and greatly improves the manufacturing efficiency, and on the other hand, it eliminates the possible influence on product quality caused by unfavorable support. Especially for thin-shell parts, some support materials even account for more than 60% of the overall material consumption. If the part is printed without support, the cost is expected to be saved by more than 50%, and the manufacturing cycle will be shortened by more than 40%. And don't have to worry about the quality issues that support removal may cause.

Description of drawings

FIG. 1 is an overall structural diagram of the unsupported 3D suspension printing structure of the present invention.

FIG. 2 is a schematic diagram of a sound field construction structure of the present invention.

In the figure: 1 is the buzzer array, 2 is the ultrasonic phase array bracket, 3 is the ultrasonic transmitting power supply and control mechanism, and 4 is the 3D printing head.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings.

Refer to Figures 1 to 2, which are structural diagrams of unsupported 3D suspension printing, wherein Figure 1 is a diagram of the overall 3D printing equipment, including the sound field layout and print head layout; Figure 2 takes out the sound field part alone, and its structure includes the construction of the sound field. The generating power, the transmitting end and the reflecting end connected with the generating power wire.

An unsupported 3D suspension printing structure provided by the present invention includes an ultrasonic phase array bracket 2 , a buzzer array 1 arranged on both sides of the ultrasonic phase array bracket 2 , an ultrasonic transmitting power source and a control mechanism connected to the buzzer array 1 . 3, and the 3D printing head 4 arranged above the ultrasonic phase array bracket 2, wherein the two groups of buzzer arrays 1 respectively form the transmitting end and the reflecting end of the suspended sound field, and each group of buzzer arrays 1 includes dozens of up to Hundreds of buzzers.

An unsupported 3D suspension printing method provided by the present invention includes the following steps:

1) According to the printing size, take dozens to hundreds of buzzers, and combine them with their brackets to form a certain shape to form a transmitting end and a reflecting end, and construct a suspended sound field;

2) Design a reasonable nozzle diameter of the print head to ensure that the weight of the extruded filament is not higher than the radiation force of the sound field; the nozzle diameter of the print head needs to consider the balance between the quality of the filament and the radiation force of the suspension field, and a diameter of 0.4mm can be used Or a nozzle diameter of 0.8mm; and the quality and feeding method of the nozzle of the print head must have a certain anti-interference ability to ensure the stability of the suspension of the silk;

3) Effectively integrate the ultrasonic field structure with the 3D printer, and do a good job of avoiding the structure, so that the print head is often in the sound field;

4) Adjust and match the parameters of the ultrasonic transmitting power source and the ultrasonic transmitting end and the reflecting end well, and provide enough sound radiation force to make dozens of nodes appear in the area. The sound field and the printing mechanism need reasonable avoidance, and the printing head is often in the sound field. ;

5) Adjust the relationship between the sound field and the printing temperature field, and at the same time adjust the printing synchronization time of the two to the suspended or floating parts, to ensure that the overall temperature of the printing area is controlled below 40 degrees.

Claims (1)

1. An unsupported 3D suspension printing method, characterized in that, the method is based on an unsupported 3D suspension printing structure, comprising an ultrasonic phase array bracket (2), and buzzers arranged on both sides of the ultrasonic phase array bracket (2) a buzzer array (1), an ultrasonic transmitting power supply and a control mechanism (3) connected to the buzzer array (1), and a 3D printing head (4) arranged above the ultrasonic phase array bracket (2), wherein two groups of buzzer The buzzer array (1) respectively forms the transmitting end and the reflecting end of the suspended sound field, and the suspended sound field is a standing wave suspended sound field; each group of buzzer arrays (1) includes dozens to hundreds of buzzers; Include the following steps: 1) Design the suspended sound field according to the situation of the 3D printing equipment, the 3D printing equipment is an FDM printer, or a jet printing equipment, and the printing material of the FDM printer is a thermoplastic material; 2) Adjust the process parameters of the nozzle diameter, temperature and wire feeding speed of the print head, and the nozzle diameter of the print head is 0.4mm or 0.8mm; 3) Combine the constructed suspended sound field with the existing 3D printing equipment; 4) The suspended sound field is composed of a buzzer array, and the ultrasonic frequency and amplitude are adjusted until there are more nodes, so that the nodes can support the continuous filament, and the printing material can form a stable floating point in the 3D printing equipment; 5) The overall control of the coordination relationship between the floating point and the printing filament, to realize the coupling printing between each other, the coupling relationship refers to the coupling of the thermal field and the sound field, and at the same time adjust the printing synchronization time of the two to the floating or floating parts to ensure The overall temperature of the printing area is controlled below 40 degrees.

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