Nozzle servicing techniques for additive fabrication systems

Patent metadata

Field	Value
Publication number	US-2019118258-A1
Application number	US-201816125181-A
Country	US
Kind code	A1
Filing date	Sep 7, 2018
Priority date	Oct 20, 2017
Publication date	Apr 25, 2019
Grant date	—

Abstract

3D printing using metal containing multi phase materials is prone to nozzle clogging and flow artifacts. These can be mitigated by monitoring process conditions and taking action at times based on other conditions. Forces, physical regularity, and temperatures can be monitored and service can be taken based on these, immediately, or at dynamic future points, short or longer term, such as completion of a segment or layer, or before critical geometry. Process conditions can be logged and service time can be based on functions of individual and combinations of logged data. Operating windows can be adjusted based on same. Service includes dwell time at high and low temperatures, treatment material provided into the nozzle to change the liquid composition therein. Plungers and fluid jets can expel material from nozzle inlet or outlet. Dwelling at various temperatures can liquefy clogs or cause rupture by disparate volume changes of cooling materials.

First claim

What is claimed is:

1 . A method for servicing a nozzle of a three-dimensional printer used for fabricating an object based on a computerized model of the object by extruding metal containing multi-phase (MCMP) build material from the nozzle, the printer also comprising a build region, the nozzle having an inlet and an outlet, the steps of fabrication including feeding the MCMP build material into the nozzle inlet, and extruding MCMP build material from the nozzle outlet while establishing relative motion of the nozzle outlet relative to the build region along a build path to fabricate the object within the build region, the method for servicing comprising:
a. establishing a size of at least one operating window, at the conclusion of which nozzle service is scheduled; b. establishing at least one process condition; c. during the operating window, simultaneously with the steps of feeding, extruding, and establishing relative motion of the nozzle outlet, monitoring at least one processing condition;
i. if the at least one processing condition has not arisen, continuing with the steps of feeding, extruding, and establishing relative motion of the nozzle outlet and simultaneously monitoring whether the at least one processing condition has arisen; and
ii. if the at least one processing condition has arisen:
A. changing the size of the operating window;
B. continuing the steps of feeding, extruding, and establishing relative motion of the nozzle outlet until conclusion of the operating window with a changed size, and then conducting nozzle service; and
C. conducting step c. above during the operating window with the changed size.

2 . The method of claim 1 , the step c. ii. B, further comprising monitoring whether the at least one processing condition has arisen, and if it has, again changing the size of the operating window

3 . The method of claim 2 , the steps of continuing the steps of feeding, extruding and establishing relative motion of the nozzle outlet until conclusion of the operating window with changed size comprising continuing the steps of feeding, extruding and establishing relative motion of the nozzle outlet until conclusion of the operating window with again changed size.

4 . The method of claim 1 , the printer further comprising a build material feeder system, the at least one process condition being selected from the group consisting of: extrusion force, optically observed condition of build material as extruded, elapsed extrusion time, distance of material deposited, mass of material deposited, volume of material deposited, number of segments deposited, number of layers deposited, average of any of the foregoing, moving average of any of the foregoing, and exponentially weighted moving average of any of the foregoing.

5 . The method of claim 1 , the steps of feeding the build material into the nozzle inlet and extruding build material from the nozzle outlet to fabricate the object on the build region comprising extruding build material in a set of individual segments, the step of changing the size of the operating window comprising changing it to a size so that it terminates after completion of an individual segment and before beginning an individual segment.

6 . The method of claim 1 , the at least one processing condition comprising a dynamic value.

7 . A method for servicing a nozzle of a three-dimensional printer used for fabricating an object based on a computerized model of the object by extruding metal containing multi-phase (MCMP) build material from the nozzle, the printer also comprising a build region, the nozzle having an inlet and an outlet, the steps of fabrication including feeding the MCMP build material into the nozzle inlet, and extruding MCMP build material from the nozzle outlet while establishing relative motion of the nozzle outlet in a set of individual segments relative to the build region along a build path to fabricate the object within the build region, the method for servicing comprising:
a. establishing at least one operating window, at the conclusion of which nozzle service is scheduled; b. establishing at least one process condition; and c. during the operating window, simultaneously with feeding, extruding, and establishing relative motion of the nozzle outlet, monitoring at least one process condition:
i. if the at least one processing condition has not arisen, continuing with feeding, extruding, and establishing relative motion of the nozzle outlet and simultaneously monitoring whether the at least one processing condition has arisen until conclusion of the operating window; and
ii. if the at least one processing condition has arisen, continuing the steps of feeding, extruding and establishing relative motion of the nozzle outlet until after a segment has been extruded, and then, before extruding an additional segment, conducting nozzle service.

8 . The method of claim 7 , the processing condition having arisen when a specific segment was being extruded, the step of continuing the steps of feeding, extruding and establishing relative motion of the nozzle outlet until after a segment has been extruded comprising continuing the steps of feeding, extruding and establishing relative motion of the nozzle outlet until after the segment that was being extruded when the processing condition arose, has been extruded.

9 . The method of claim 7 , the processing condition having arisen when a specific segment was being extruded, the step of continuing the steps of feeding, extruding and establishing relative motion of the nozzle outlet until after a segment has been extruded comprising continuing the steps of feeding, extruding and establishing relative motion of the nozzle outlet until after a plurality of segments have been extruded after the segment that was being extruded when the processing condition arose, has been extruded.

10 . The method of claim 7 , the at least one process condition comprising an extrapolation function of a measured parameter over time.

11 . The method of claim 10 , the extrapolation function of a measured parameter over time comprising an extrapolation function of a plurality of measured parameters over time.

12 . A method for servicing a nozzle of a three-dimensional printer used for fabricating an object based on a computerized model of the object by extruding metal containing multi-phase (MCMP) build material from the nozzle, the printer also comprising a build region, the nozzle having an inlet and an outlet, the steps of fabrication including feeding the MCMP build material into the nozzle inlet, and extruding MCMP build material from the nozzle outlet in a set of individual segments, each segment having a size, while establishing relative motion of the nozzle outlet relative to the build region along a build path to fabricate the object within the build region, the method for servicing comprising:
a. establishing at least one operating window, at the conclusion of which a nozzle service is scheduled; b. establishing at least process condition; and c. during the operating window, simultaneously with feeding, extruding, and moving the nozzle, monitoring at least one process condition, and determining whether the at least one process condition will arise before completion of an upcoming segment:
i. if the at least one processing condition will not arise before completion of an upcoming segment, continuing with feeding, extruding, and establishing relative motion of the nozzle outlet and determining whether the at least one process condition will arise before completion of an upcoming segment; and
ii. if the at least one processing condition will arise before completion of an upcomi

Assignees

• Desktop Metal Inc

Inventors

• Sachs Emanuel Michael
• Bauer Uwe
• Bandiera Nicholas Graham
• Gibson Mark Gardner

Classifications

• B22F10/31

  Calibration of process steps or apparatus settings, e.g. before or during manufacturing · CPC title

• B22F10/18

  by mixing binder with metal in filament form, e.g. fused filament fabrication [FFF] · CPC title

• B22F12/22

  Driving means · CPC title

• B22F12/55

  Two or more means for feeding material · CPC title

• B22F12/13

  to preheat the material · CPC title