Photoelectric detection method of powder spreading amount for rapid prototyping

Abstract

The invention discloses a photoelectric detection method for rapid prototyping powder spreading. The system adopted includes a powder flow detection mechanism, a controller and a computer. A sensor, a light-transmitting tube and a timer; the method includes the steps of: 1. opening a tube hole on the powder spreading platform, and fixing the upper and lower powder tubes at the tube hole; The signal is detected, and the timer transmits the timing of the powder flowing through the light-transmitting tube to the controller; 3. The controller substitutes the time of powder flowing through the light-transmitting tube into the amount of powder spread and the powder flowing through the light-transmitting tube. In the relational model of the tube time, the amount of powder spread is calculated and transmitted to the computer for display. The present invention can realize the real-time quantitative detection of the current powder coating amount, can make the powder coating amount visualized and correctable, facilitates the required powder coating amount, and can improve the forming accuracy and quality of parts.

Description

technical field [0001] The invention belongs to the technical field of rapid prototyping, and in particular relates to a photoelectric detection method for powder spreading amount of rapid prototyping. Background technique [0002] Automatic powder-spreading high-energy beam selective melting technology is a newly developed direct 3D printing technology for metal parts. Its principle is to use a computer to layer the 3D CAD model and process the cross-section information, and then input the cross-section data into the 3D printer. The data spreads the metal powder layer by layer and uses the high-energy beam to melt the selected area of ​​the powder layer. After all the cross-sections are melted layer by layer and superimposed, the three-dimensional solid parts of the designed structural shape are obtained. The powder spreading process is a key process in the automatic powder spreading high-energy beam selective melting technology. The thickness and uniformity of the powder l...

AI Technical Summary

Problems solved by technology

However, since it is difficult to directly and accurately detect the amount of powder spreading powder, in the current commonly used scraper / sheet powder spreading method, the powder spreading mechanism is used to spread powder on the powder spreading platform, and the powder spreading scraper is installed in the powder spreading mechanism. Control the landing of the forming platform to control the thickness of the powder layer. There is no rapid prototyping powder amount detection device, and it is impossible to accurately detect the amount of powder in real time, and it is impossible to make real-time compensation and adjustment according to the actual powder demand, which affects the high-energy beam selective melting process. Optimization adjustment

If the amount of powder spread is too small, the powder spread in the powder spread area will be incomplete, which will cause the error of the forming size of the part. The formation is terminated due to powder, which seriously affects the stability of the high-energy beam selective melting process, and the formed parts are often defective or scrapped.

[0003] In order to solve the above problems, some people use the weighing method to detect the amount of powder spreading, but because the amount of powder spreading each time is small, it is difficult to measure accurately. At the same time, the structure of the weighing mechanism is complicated, the cost is high, and the reliability is poor; some people use quantitative powder feeding method to determine the amount of powder to be spread, but due to lack of flexibility, it is difficult to compensate and adjust the amount of powder in real time according to the actual situation. The forming of the part will fail. If 2 to 4 times the required amount of powder is used to spread the powder in order to ensure the thickness of the powder layer, it will cause serious waste of powder.

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