Fluid propelling apparatus including a heat sink

Patent metadata

Field	Value
Publication number	US-11235574-B2
Application number	US-201615772377-A
Country	US
Kind code	B2
Filing date	Feb 29, 2016
Priority date	Feb 29, 2016
Publication date	Feb 1, 2022
Grant date	Feb 1, 2022

Abstract

A fluid propelling apparatus, including a plastic compound, a MEMS at least partially surrounded by the compound, and a heat sink next to the MEMS, to transfer heat away from the MEMS, wherein the heat sink is at least partly surrounded by the compound.

First claim

What is claimed:

1. A fluid propelling apparatus, comprising
a plastic compound structure having a first fluid channel;
a MEMS embedded in the compound structure such that the MEMS is adjacent to the compound structure at three sides of the MEMS, the MEMS including a substrate, a second fluid channel fluidically connected to the first fluid channel, and a column of fluid propelling actuators in the second fluid channel, wherein the first fluid channel does not extend past the second fluid channel; and
a heat sink, at least partly surrounded by the compound structure to transfer heat away from the MEMS, wherein
the MEMS has a width less than 2.3 millimeters and a thickness less than 0.8 millimeters, and
the actuators of the column have a density of at least 300 actuators per inch of length.

2. The fluid propelling apparatus of claim 1 wherein the heat sink extends along at least half of the length of the MEMS.

3. The fluid propelling apparatus of claim 1 wherein a total volume of the heat sink is larger than a total volume of the MEMS.

4. The fluid propelling apparatus of claim 1 wherein
the substrate comprises silicon and the second fluid channel extends through the substrate, connecting to the first fluid channel,
the MEMS comprises a thin film structure on the substrate, near a front face, with nozzles connected to the second fluid channel to expel fluid, and
the heat sink extends next to the MEMS.

5. The fluid propelling apparatus of claim 4 wherein the actuators expel fluid from the nozzles.

6. The fluid propelling apparatus of claim 1 wherein the actuators include thermal resistors to act as pumps to circulate fluid through the second channel.

7. The fluid propelling apparatus of claim 1 wherein the compound structure extends between the MEMS and the heat sink.

8. The fluid propelling apparatus of claim 1 wherein the compound structure includes a first compound and a differently composed second compound of higher thermal conductivity than the first compound, wherein the MEMS and the heat sink are at least partially embedded in the second compound.

9. The fluid propelling apparatus of claim 1 wherein the MEMS is a first MEMS, the fluid propelling apparatus includes a plurality of longitudinally shaped MEMS arranged in parallel, and the first MEMS is one of the longitudinally shaped MEMS.

10. The fluid propelling apparatus of claim 9 wherein the plurality of longitudinally shaped MEMS further includes a second MEMS, and wherein the heat sink extends adjacent at least the first MEMS and the second MEMS to conduct heat away from the first MEMS and the second MEMS.

11. The fluid propelling apparatus of claim 10 wherein the heat sink is a first heat sink, the fluid propelling apparatus including a plurality of heat sinks including the first heat sink, and where the heat sinks are greater than the MEMS in number.

12. The fluid propelling apparatus of claim 1 wherein the heat sink is completely surrounded by the compound.

13. The fluid propelling apparatus of claim 1 wherein the heat sink is at least partially exposed to ambient air or fluid.

14. Method of manufacturing a fluid propelling apparatus, comprising
providing, in a mold:
a MEMS including a substrate, a fluid channel and a column of actuators in the fluid channel, the MEMS having a width less than 2.3 millimeters and a thickness less than 0.8 millimeters, the actuators of the column having a density of at least 300 actuators per inch of length,
a heat sink, adjacent the MEMS to transfer heat away from the MEMS, and
a plastic compound in an at least partly molten state;

compressing and curing the compound in the mold so that the MEMS and heat sink are fixed in position in the compound after curing, the MEMS is embedded in a compound structure comprising the compound such that the MEMS is adjacent to the compound structure at three sides of the MEMS, and the heat sink is at least partly surrounded by the compound structure; and
aligning a fluid channel in the compound structure with the fluid channel in the MEMS, the fluid channel in the compound structure not extending past the fluid channel in the MEMS.

15. Method of claim 14 including adhering the heat sink to the MEMS before placement in the mold.

16. Method of manufacturing a fluid propelling apparatus, comprising
placing a fluid propelling MEMS and a heat sink against a release tape in a mold, wherein the MEMS has a width less than 2.3 millimeters and a thickness less than 0.8 millimeters, is largely composed of silicon, the MEMS having a fluid channel and a column of actuators in the fluid channel, the actuators of the column having a density of at least 300 actuators per inch of length;
depositing a plastic compound in the mold to at least partially cover at least one of the MEMS and heat sink;
compressing the compound in the mold so that it at least partially surrounds the MEMS and heat sink;
curing the compound whereby the heat sink and MEMS are fixed in position in the compound, the MEMS is embedded in a compound structure comprising the compound such that the MEMS is adjacent to the compound structure at three sides of the MEMS, and the heat sink is at least partly surrounded by the compound structure;
aligning a fluid channel in the compound structure with the fluid channel in the MEMS, the fluid channel in the compound structure not extending past the fluid channel in the MEMS; and
releasing the release tape.

Assignees

• Hewlett Packard Development Co

Inventors

• Clark Garrett E
• Cumbie Michael W
• Chen Chien-Hua

Classifications

• B81B1/006

  Microdevices formed as a single homogeneous piece, i.e. wherein the mechanical function is obtained by the use of the device, e.g. cutters · CPC title

• B41J2202/12

  with ink circulating through the whole print head · CPC title

• B41J2/1408

  Structure dealing with thermal variations, e.g. cooling device, thermal coefficients of materials · CPC title

• B41J2/1404 Primary

  Geometrical characteristics · CPC title

• F04B19/006

  Micropumps (F04B43/043 and F04B43/095 take precedence) · CPC title