Liquefier assembly with multiple-zone plate heater assembly

Patent metadata

Field	Value
Publication number	US-2015097053-A1
Application number	US-201314046301-A
Country	US
Kind code	A1
Filing date	Oct 4, 2013
Priority date	Oct 4, 2013
Publication date	Apr 9, 2015
Grant date	—

Abstract

A liquefier assembly for use in an additive manufacturing system, which includes a rigid member having a gap, a liquefier tube operably disposed in the gap, one or more heater assemblies disposed in the gap in contact with the liquefier tube, and configured to heat the liquefier tube in a zone-by-zone manner, preferably one or more thermal resistors disposed in the gap between the rigid member and the heater assemblies, and preferably one or more sensors configured to operably measure pressure within the liquefier tube. The one or more heater assemblies may be operated to provide dynamic heat flow control.

First claim

1 . A liquefier assembly for use in an additive manufacturing system, the liquefier assembly comprising:
a liquefier tube having an inlet end and an outlet end offset along the longitudinal axis; a plate heater assembly comprising:
a plate portion;
a plurality of conductor traces disposed on the plate portion, and configured to operably receive electrical power from the additive manufacturing system with independently controlled wattage levels; and
a plurality of heating elements disposed on the plate portion, and each in contact with one or more of the conductor traces to receive the electrical power from the one or more conductor traces, wherein the independently controlled wattage levels cause the heating elements to independently heat different zones of the liquefier tube along the longitudinal axis.

2 . The liquefier assembly of claim 1 , wherein the plurality of conductor traces include three to eleven conductor traces.

3 . The liquefier assembly of claim 1 , wherein the liquefier tube comprises a ribbon liquefier tube.

4 . The liquefier assembly of claim 1 , wherein the liquefier tube comprises a cylindrical liquefier tube.

5 . The liquefier assembly of claim 1 , wherein the heater assembly is configured to operably measure temperatures of the different zones based on electrical resistances of heating elements in each of the different zones.

6 . The liquefier assembly of claim 1 , and further comprising a thermal resistor disposed against the plate heater assembly, opposite of the liquefier tube.

7 . The liquefier assembly of claim 1 , wherein plate portion comprises a section that is not in contact with the liquefier tube, and which is configured to engage with an electrical connector (not shown) of a print head that retains the liquefier assembly.

8 . A liquefier assembly for use in an additive manufacturing system, the liquefier assembly comprising:
a liquefier tube having an inlet end and an outlet end offset along the longitudinal axis; a first heater assembly comprising:
a plurality of first conductor traces; and
a plurality of first heating elements in contact with the first conductor traces to receive electrical power from the first conductor traces; and
a second heater assembly comprising:
a plurality of second conductor traces; and
a plurality of second heating elements in contact with the second conductor traces to receive electrical power from the second conductor traces, wherein the first and second heating elements are disposed symmetrically on opposing sides of the liquefier tube along the longitudinal axis to heat the liquefier tube in a zone-by-zone manner.

9 . The liquefier assembly of claim 8 , wherein the first and second conductor traces include the same number of conductor traces ranging from three to eleven conductor traces.

10 . The liquefier assembly of claim 8 , wherein the liquefier tube comprises a ribbon liquefier tube.

11 . The liquefier assembly of claim 10 , wherein the ribbon liquefier tube has a substantially rectangular cross-section.

12 . The liquefier assembly of claim 8 , wherein the liquefier tube comprises a cylindrical liquefier tube.

13 . The liquefier assembly of claim 8 , wherein the liquefier tube has a length between the inlet end and the outlet end ranging from about 0.3 inch to about 5 inches.

14 . The liquefier assembly of claim 8 , and further comprising:
a first thermal resistor disposed against the first heater assembly, opposite of the liquefier tube; and a second thermal resistor disposed against the second heater assembly, opposite of the liquefier tube.

15 . A print head for use in an additive manufacturing system, the print head comprising:
a drive mechanism configured to feed a consumable material at multiple feed rates; a liquefier tube configured to receive the fed consumable material; and at least one plate heater assembly comprising a plurality of conductor traces and a plurality of heating elements in contact with the conductor traces, wherein the conductor traces are configured to relay electrical power to the heating elements to generate multiple heating zones along the liquefier tube that independently adjust in temperature in association with changes in the feed rates of the consumable material.

16 . The print head of claim 15 , and further comprising a housing, wherein the drive mechanism is disposed at least partially within the housing.

17 . The print head of claim 15 , wherein the liquefier tube comprises a ribbon liquefier tube.

18 . The print head of claim 15 , wherein the liquefier tube comprises a cylindrical liquefier tube.

19 . The print head of claim 15 , wherein the liquefier tube has a length between the inlet end and the outlet end ranging from about 0.3 inch to about 5 inches.

20 . The print head of claim 15 , wherein the at least one plate heater assembly comprises two plate heater assemblies disposed on opposing sides of the liquefier tube.

Assignees

• Stratasys Inc

Inventors

• Batchelder J Samuel
• Swanson William J
• Johnson Kevin C

Classifications

• B33Y30/00 Primary

  Apparatus for additive manufacturing; Details thereof or accessories therefor · CPC title

• B29C64/209 Primary

  Heads; Nozzles · CPC title

• F24H9/06 Primary

  Arrangement of mountings or supports · CPC title