Closed-loop negative-pressure powder circulating system and laser sintering equipment

Abstract

The invention provides a closed-loop negative-pressure powder circulating system and laser sintering equipment. The closed-loop negative-pressure powder circulating system comprises a negative-pressure pump, a pressure relief assembly, a first separator, a first powder storage part and a powder feeding part. The pressure relief assembly comprises an exhaust pipe, a pressure relief valve and a one-way valve, the pressure relief valve and the one-way valve are arranged on the exhaust pipe, the exhaust pipe is communicated with an air outlet of the negative pressure pump, and the one-way valve only allows fluid in the exhaust pipe to be discharged. A first separation cavity of the first separator is communicated with an air outlet of the negative pressure pump, and an air outlet of the first separator is communicated with an air suction port of the negative pressure pump. And a discharge hole of the first powder storage piece is communicated with a pipeline which is communicated with the first separation chamber and an air outlet of the negative pressure pump. And the powder feeding piece is communicated with a discharge hole of the first separator. According to the powder circulating system, closed-loop negative-pressure powder feeding is adopted, so that the oxygen content of the system is stable, and product forming is facilitated; the powder is not easy to leak, and is safe and reliable.

Description

technical field [0001] The invention relates to the technical field of 3D molding, in particular to a closed-loop negative pressure powder circulation system and laser sintering equipment. Background technique [0002] Selective laser sintering is an advanced manufacturing technology with distinctive features such as digital manufacturing, high flexibility and adaptability, direct CAD model drive, fast speed, and rich and diverse material types. Since its development in the late 1980s, it has become a modern A pillar technology in advanced manufacturing technology. The sintering process of selective laser sintering equipment includes powder supply, powder recovery and powder post-processing. At present, the powder supply and recovery of small-scale selective laser sintering equipment are generally operated manually. During the sintering process, the operator manually disassembles and replaces the tank for powder supply and recovery. In the application of large-scale select...

AI Technical Summary

Problems solved by technology

In the application of large-scale selective laser sintering equipment, the positive pressure powder delivery method is generally adopted. This method is prone to powder blockage in the pipeline and a large amount of backflow powder in the return air pipeline, resulting in termination of sintering and waste of powder. There are environmental safety hazards. For example, due to the positive pressure in the pipeline, if there is an air leak on the pipeline, the powder can be sprayed out from the air leak and pollute the air, especially when sintering active metals (titanium alloy, aluminum alloy, etc.) , these metal powders are mixed into the air, which poses a considerable safety hazard

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