Controlling heating in additive manufacturing

Patent metadata

Field	Value
Publication number	US-2019111630-A1
Application number	US-201616097266-A
Country	US
Kind code	A1
Filing date	Jul 22, 2016
Priority date	Jul 22, 2016
Publication date	Apr 18, 2019
Grant date	—

Abstract

According to some examples, a method comprises measuring, using a detector, a temperature of at least a portion of a layer of build material formed on a print bed associated with an additive manufacturing apparatus. The additive manufacturing apparatus may include a heating module to direct heat towards successive layers of build material during a series of successive passes over the build material. The method may further comprise determining, using a processor, based at least in part on the measured temperature, a duration that the heating module is to wait before performing a pass over the build material, and a speed at which the heating module is to travel over the build material.

First claim

1 . A method comprising:
measuring, using a detector, a temperature of at least a portion of a layer of build material formed on a print bed associated with an additive manufacturing apparatus, the additive manufacturing apparatus including a heating module to direct heat towards successive layers of build material during a series of successive passes over the build material; and determining, using a processor, based at least in part on the measured temperature, a duration that the heating module is to wait before performing a pass over the build material, and a speed at which the heating module is to travel over the build material.

2 . The method of claim 1 , further comprising:
controlling the heating module to wait for the determined duration.

3 . The method of claim 1 , further comprising:
controlling the heating module to travel over the build material at the determined speed.

4 . The method of claim 1 , wherein, determining the duration is based on at least one of:
i) a difference between the measured temperature and a target temperature; ii) a temperature of at least a portion of a layer of build material as measured prior to a preceding pass over the build material; iii) a determined rate of change of a temperature of build material over successive passes; and iv) a volume of a three-dimensional object to be generated by processing the successive layers of build material.

5 . The method of claim 1 , further comprising:
distributing, during a first pass over a layer the build material, print agent onto at least a portion of the build material; and operating the heating module to travel at the determined speed during a second pass over the build material.

6 . The method of claim 5 , wherein, during the first pass, the heating module is to increase a temperature of the build material to a first temperature and, during the second pass, the heating module is to increase the temperature of build material to which print agent has been applied to a second, higher temperature.

7 . The method of claim 5 , wherein, for all of the passes during which print agent is to be distributed onto at least a portion of build material, the speed at which the heating module is to travel is constant.

8 . Additive manufacturing apparatus comprising:
a heating assembly to direct heat towards layers of build material formed on a print bed associated with the additive manufacturing apparatus during a series of passes over the print bed; a temperature measurement element to determine a temperature of at least a portion of a layer of build material; and processing apparatus to calculate, based at least in part on the determined temperature:
an amount of time that the heating assembly is to wait between a first pass over the print bed and a second pass over the print bed; and
a rate of movement of the heating assembly during the second pass.

9 . Additive manufacturing apparatus according to claim 8 , wherein the heating assembly forms part of, or is coupled to, a carriage for moving a print agent distributor, the print agent distributor to selectively deliver print agent to at least a portion of a layer of build material.

10 . Additive manufacturing apparatus according to claim 8 , wherein the heating assembly forms part of, or is coupled to, a carriage for moving a build material distributor, the build material distributor to distribute layers of build material over the print bed.

11 . Additive manufacturing apparatus according to claim 8 , wherein the heating assembly comprises a plurality of heating elements, and wherein, during a pass over the build material, a power output of the each of the heating elements remains constant.

12 . Additive manufacturing apparatus according to claim 8 , wherein the processing apparatus is to:
operate the heating assembly to wait for the calculated amount of time; and operate the heating assembly to pass over the print bed at the calculated rate.

13 . A machine readable medium comprising instructions which, when executed by a processor, cause the processor to:
control a lamp assembly to pass over each of a plurality of layers of build material formed on a print bed of an additive manufacturing apparatus so as to direct heat towards each layer of build material; establish, based at least in part on a measured temperature of at least a portion of a layer of the build material:
a duration that the lamp assembly is to wait before beginning to pass over a layer of build material; and
a speed at which the lamp assembly is to travel over the build material;
control the lamp assembly to wait for the established duration; and control the lamp assembly to perform a pass over the build material at the established speed.

14 . A machine readable medium according to claim 13 , further comprising instructions which, when executed by a processor, cause the processor to:
control the lamp assembly to wait for the established duration.

15 . A machine readable medium according to claim 13 , further comprising instructions which, when executed by a processor, cause the processor to:
control the lamp assembly to travel over the build material at the established speed.

Assignees

• Hewlett Packard Development Co

Inventors

• Tarradas Anna
• Vilajosana Xavier
• Mostaccio Diego Javier

Classifications

• B22F10/30

  Process control · CPC title

• B22F10/28

  Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM] · CPC title

• B22F12/53

  Nozzles · CPC title

• B22F12/13

  to preheat the material · CPC title

• B22F12/90

  Means for process control, e.g. cameras or sensors · CPC title