69 patents in this list

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In powder-based additive manufacturing, process gases and particulates can significantly impact print quality and worker safety. Chamber atmospheres contain metal particles ranging from 0.1-100μm, volatile organic compounds, and process gases that must be efficiently evacuated while maintaining strict temperature control and inert gas concentrations for sensitive materials.

The fundamental challenge lies in removing contaminated gases and particles without disrupting the carefully controlled thermal and atmospheric conditions needed for consistent print quality.

This page brings together solutions from recent research—including laminar flow gas delivery systems, multi-zone extraction manifolds, pressure-regulated recirculation loops, and intelligent purging mechanisms. These and other approaches focus on maintaining print quality while addressing both safety requirements and process gas conservation needs.

1. Closed-Loop Gas Circulation System with Real-Time Oxygen and Pressure Monitoring for Metal 3D Printers

Foshan University of Science and Technology, FOSHAN UNIVERSITY, 2024

Intelligent deoxygenation and purification system for metal 3D printers that reduces oxygen content, improves print quality, and saves gas consumption. The system uses a closed-loop gas circulation with vacuum pump, filters, and solenoid valves to continuously clean and deoxygenate the printing chamber. It also detects oxygen and pressure levels in real-time to optimize conditions and prevent contamination. The loop recirculates gas through a filter, smoke purifier, and exhaust to remove impurities and reduce oxygen. This avoids excessive gas consumption compared to periodic purging.

2. Impurity Removal Device for 3D Printer Gas Supply with Oxygen Reduction and Metal-Based Filtration

KOREA INSTITUTE OF MACHINERY & MAT, KOREA INSTITUTE OF MACHINERY & MATERIALS, 2024

Impurity removal device for 3D printers that reduces oxygen concentration in the print chamber gas to prevent defects in printed parts. The device has a gas supply unit, a removal body that removes impurities by heating, and a removal unit containing metal like titanium or alloys like magnesium, aluminum, calcium. Before supplying the gas to the printer, oxygen is removed using the device. A filter removes moisture/CO2. A mixing unit combines powder and gas. This prevents oxygen-containing gases from printing metal parts with affinity for oxygen.

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3. External Gas Purification Device with Sealed Filter Housing and Chamber-Connected Channels for 3D Printers

ZHONGSHAN HUAYU YUANXING ELECTRONIC TECH CO LTD, ZHONGSHAN HUAYU YUANXING ELECTRONIC TECHNOLOGY CO LTD, 2023

A removable gas purification device for 3D printers that attaches externally to the printer and connects to the print chamber. The device has a filter element inside a sealed housing. It draws air from the print chamber through an inlet, filters the gases, then returns the purified air through an outlet back into the chamber. This allows external filtration and reduces heat loss compared to internal filters. The device attaches behind the printer's fan and accelerates part curing. The filter housing has channels to connect to the print chamber and fan.

4. 3D Printing Gas Circuit with Separable Filter Chambers and Differential Pressure Monitoring

EOS GMBH ELECTRO OPTICAL SYSTEMS, 2023

A device and method to improve quality of 3D printed objects by optimizing the process gas environment. The device has multiple separable filter chambers in the gas circuit that can be individually isolated during printing. This allows cleaning or replacing filters without interrupting printing. It uses sensors to monitor differential pressure across filters and volume flow. Cleaning is triggered when thresholds are exceeded. This prevents sudden flow changes from separating filters.

5. Negative Pressure Powder Feeding System with Sealed Transition Chamber and Inert Gas Management for Additive Manufacturing

NINGBO HAITIAN ADDITIVE TECH CO LTD, NINGBO HAITIAN ADDITIVE TECHNOLOGY CO LTD, 2023

Negative pressure powder feeding system for additive manufacturing that addresses issues of powder clogging, oxygen content, and efficiency compared to prior systems like manual, positive pressure, and negative pressure feeding. The system uses a sealed transition chamber with an inert gas inlet that can be opened after powder reaches a certain height. This dilutes the oxygen content in the chamber before printing starts. A blower evacuates the chamber, preventing powder clogging and sealing issues. The system also has a filter and pulse valve to prevent powder blocking the exhaust. The chamber can be pressurized with inert gas between prints to further lower oxygen levels.

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6. Additive Manufacturing System with Dual Gas Flow Configuration for Smoke and Particle Removal

General Electric Company, 2023

An additive manufacturing system that uses gas flow to remove smoke and particles from the chamber during manufacturing, improving the quality of printed objects. The system has an upper gas flow along the build platform and a lower gas flow directed parallel to the platform. The lower gas is introduced above or below the platform and guided by a contoured surface to flow parallel to the platform surface. This gas flow configuration prevents recirculation and efficiently removes smoke and particles from the chamber.

7. Gas Extraction System with Dual Conduit Configuration and Flow Control for 3D Printing Apparatus

Stratasys Powder Production Ltd., 2023

A gas extraction system for a 3D printing apparatus that allows precise control of the temperature and airflow in the printing chamber. The system uses a primary conduit with a primary inlet, interfacing inlet, and outlet. A secondary conduit connects the primary conduit to the working space inlet. Flow control devices regulate the flow of gas from the working space into the secondary conduit, which is then suctioned out by an external extraction source. This allows precise control of the temperature and airflow in the printing chamber while removing fumes and byproducts.

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8. Additive Manufacturing Chamber with Automated Evacuation Gas Flow Streamlining Mechanism

The Boeing Company, 2023

Automated optimization of evacuation gas flow (EGF) in additive manufacturing (AM) build chambers to improve component quality. The method involves receiving input parameters like chamber geometry and operating conditions, simulating gas flow in the modified chamber, extracting evacuation streamlines, and calculating flow improvements using a metric. This iterative process resolves an optimal chamber design with maximized EGF.

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9. Fume Extraction System with Recirculating Filtration and Adjustable Operation Modes for 3D Printers

Donaldson Company, Inc., 2023

A fume extraction system for 3D printers that allows printing at high temperatures without releasing noxious fumes. A pump pulls air from the printer chamber through a filter to remove particulates and fumes. The filtered air is returned to the chamber. The filter contains an adsorption filter to remove noxious fumes. The system can operate in different modes during printing to maintain chamber pressure and temperature.

10. Fume Extraction System with Fixed-Side and Movable Central Manifolds for Additive Manufacturing Machines

AddUp, 2023

A fume extraction system for large-scale additive manufacturing machines that prevents contamination between work zones when using multiple energy beams to consolidate the powder. The system uses fixed-side manifolds and a movable central manifold above the overlap zone between adjacent work zones. The central manifold extends over the full transverse dimension and can translate longitudinally to cover the entire work surface. This allows fume extraction close to the powder without beams crossing work zones.

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11. Nozzle-Integrated Gas Filtration Device with Activated Carbon and Diatomaceous Earth Filter

MOON HYUN HUN, 2022

A device to remove harmful gases generated during 3D printing. The device is installed in the nozzle of a 3D printer and removes harmful gases like heavy metals emitted during printing. It consists of a filter unit to collect the gases and an intake unit to suck the gases into the filter. The filter contains materials like activated carbon and diatomaceous earth to absorb the harmful gases. The filter unit is located in a housing with an intake from the nozzle and an outlet to exhaust the filtered gases.

12. System for Recirculating and Purifying Displaced Process Gas in Additive Manufacturing

CONCEPT LASER GMBH, 2022

Reducing the amount of process gas wasted during additive manufacturing by collecting and reusing fluid displaced from the process chamber. The fluid is collected and/or fed back into the chamber or into another apparatus's chamber based on its process gas content. The collected fluid can be purified to increase the process gas content.

13. Additive Manufacturing Apparatus with Gas Recirculation Loop Incorporating Purification Devices

RAYTHEON TECHNOLOGIES CORPORATION, 2022

An additive manufacturing apparatus with a gas recirculation loop purifies the inert cover gas used during the process. The loop removes impurities from the cover gas to generate a clean cover gas that can be reintroduced into the chamber for the additive manufacturing process. The loop includes purification devices like particle filters and gas scrubbers to remove solid and gaseous impurities.

14. Closed-Loop Air Purification System with Vibration-Activated Pump and Adjustable Filtration for 3D Printer Enclosures

CHEONGWOO C&T CO LTD, 2022

A closed-loop system to purify the air inside a 3D printer enclosure during printing to remove harmful gases generated during the process. The system has a chamber with a removable tray for the 3D printer, an air pump, filters, and a vibration sensor. The pump sucks air from the bottom, filters it, and pumps it back. The sensor detects 3D printer vibration to start/stop the pump. It also measures air quality and adjusts pump speed. This captures and filters the toxic gases emitted during printing to prevent indoor exposure.

15. Porous Tube Gas Delivery System for Additive Manufacturing Chamber

Russell V. Hughes, Joseph Pavilanis, 2022

Gas delivery and purging device for additive manufacturing chamber to reduce purge times and gas volume by allowing a gas like argon to flow into the chamber in a non-turbulent, laminar manner that displaces other gases and forces them out. The device uses flexible tubes with pores across their entire surface area.

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16. Sealed 3D Printer Enclosure with Integrated Gas Filtration and Adjustable Leveling Mechanism

YOUZHU TECH YUXI CO LTD, YOUZHU TECHNOLOGY CO LTD, 2022

A sealed enclosure for 3D printers that captures and filters the odorous gases produced during printing to prevent operator exposure and environmental pollution. The enclosure has a door with a transparent window, adjustable feet to level the printer, and a skirt with sealing foam around the door. Inside are components like an exhaust fan, filters, gas sensor, and check valves to draw in air, filter it, and expel cleaned air. The enclosure seals tightly with compacted foam around the door panels to prevent air leaks.

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17. Circulation and Purification System for Impurity Gas in Low Positive Pressure Sealed Molding Chamber

South China University of Technology, SOUTH CHINA UNIVERSITY OF TECHNOLOGY, 2022

Method and device for circulating and purifying impurity gas in a low positive pressure sealed molding chamber used in additive manufacturing like laser selective melting (SLM). The method involves continuously circulating and purifying the gas inside the sealed molding chamber to maintain low oxygen levels, prevent oxidation, and remove metal dust particles. The purification system has a filter to collect metal dust and a feedback loop to monitor key indicators like oxygen concentration and cleanliness. This improves part quality, prevents contamination, and mitigates health risks compared to simple filters.

18. Three-Dimensional Printer Pressure Regulation Apparatus with Ambient Air Inlet Control

Hewlett-Packard Development Company, L.P., 2022

Regulating pressure within a three-dimensional printer to maintain consistent quality of printed parts. The pressure within the printer can fluctuate due to variations in the extraction rate of an external gas extraction system. An apparatus is installed in the printer that measures the pressure and compares it to a predetermined value. If the pressure is too low, the apparatus opens apertures in the printer to allow ambient air to flow into the extraction system. This stabilizes the pressure and maintains consistent part quality.

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19. Gas Circuit with Continuous Filtration and Automatic Pressure Regulation for 3D Printing Equipment

SUZHOU THREE PEAK LASER TECH LIMITED CO, SUZHOU THREE-PEAK LASER TECHNOLOGY LIMITED CO, 2022

Gas circuit for 3D printing equipment with improved reliability and reduced maintenance compared to traditional designs. The circuit includes a circulation system with filters to continuously clean and recirculate the inert gas inside the printing chamber. This prevents pollution buildup in the pressure relief components. If chamber pressure rises, a mechanical protection device automatically adjusts the pressure instead of relying solely on the pressure relief valve. This prevents sudden pressure spikes that could shut down the equipment. The circuit also has features like seals and valves to isolate and control the gas flow between components.

20. Inert Gas Recirculation System with Serial and Parallel Filtration for Metal 3D Printing Chambers

ZHEJIANG TOP ENVIRONMENTAL TECH CO LTD, ZHEJIANG TOP ENVIRONMENTAL TECHNOLOGY CO LTD, 2022

Atmosphere purification system for metal 3D printers to capture and reuse the inert gas in the printing chamber instead of continuously replacing it. The system has multiple filters arranged in series along the gas flow path. The filters are a cyclone, a high-efficiency filter, and another high-efficiency filter. Secondary filters are also parallel between the primary and tertiary filters. The secondary filters have control valves and connected backflushing gas bags. The system also has a cleaning passage connecting the printer and the atmosphere. The cleaning passage has valves, sensors, and a blower. The system purifies and reuses the inert gas by backflushing the secondary filters with the printer gas, then cleaning the filters and pipes with inert gas inflow.

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21. Process Chamber Housing with Opposing Gas Inlet and Outlet for Enhanced Gas Flow in Additive Manufacturing

22. Gas Protection Cover with Vented Platform and Two-Position Valve for 3D Printing

23. 3D Printing System with Gas Dehumidification and Recycling Mechanism Using Heat Exchanger and Chiller Control

24. Gas Extraction System with Dual Conduits and Independent Flow Control for 3D Printer Build Chambers

25. Additive Manufacturing System with Movable Gas Exchange Manifold Integrated with Recoater Mechanism

Numerous approaches to handling problems connected to gas removal are presented in the patents that are shown here. Notably, these include advanced extraction systems with temperature control capabilities, optimization techniques to increase evacuation effectiveness, and gas flow management systems to stop recirculation.

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