Potting shell

• US 7,566,836 B2
• Filed: 07/30/2004
• Issued: 07/28/2009
• Est. Priority Date: 08/29/2003
• Status: Active Grant

• Current Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Original Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Inventors: Tanner, Juergen
• Primary Examiner(s): Ngo; Hung V
• Application Number:
  US10/569,726
• Publication Number:
  US 20070165363A1
• Time in Patent Office: 1,824 Days
• Field of Search: 174/525, 174/559, 174/560, 174/521, 257/787, 361/752, 361/764
• US Class Current: 174/525
• CPC Class Codes: H01L 2924/16151 Cap comprising an aperture, e.g. for pressure control, encapsulation
• CPC Class Codes: H05K 3/284 for encapsulating mounted components H05K1/185 takes precedence
• CPC Class Codes: H05K 5/064 sealed by potting, e.g. waterproof resin poured in a rigid casing

Abstract

A potting shell, for an electronic circuit on a circuit board, comprises a wall arrangement, which defines a shell volume at least in one spatial direction and in the directions perpendicular thereto; wherein the circuit board is positionable in the shell volume, and can be potted in the shell volume with a potting compound. The volume between the circuit board and a main wall of the potting shell, running essentially parallel, at least sectionally, to the circuit board, can be filled with a potting compound, characterized in that the main wall has at least one flexible section, which, based on a thermal expansion of the potting compound, can be deformed perpendicular to the plane of the flexible section.

Claims

1. A potting shell for a populated circuit board, including:

a wall arrangement with a main wall, said wall arrangement defines a shell volume at least in one spatial direction, and in the directions perpendicular thereto, wherein;

the circuit board is positionable in the shell volume, and can be potted in the shell volume with a potting compound;

the volume between the circuit board and a main wall of the potting shell, running essentially parallel, at least sectionally, to the circuit board, can be filled with a potting compound; and

said main wall has at least one flexible section, which, based on a thermal expansion of the potting compound, can be deformed perpendicular to the plane of said flexible section.

2. The potting shell as claimed in claim 1, wherein:

said flexible section has a lesser wall thickness than other wall sections of the potting shell.

3. The potting shell as claimed in claim 2, wherein:

the wall thickness in said flexible section amounts to not more than 80% of the wall thickness outside of said flexible section.

4. The potting shell as claimed in claim 2, wherein:

the wall thickness in said flexible section amounts to not more than 80% of the wall thickness outside of said flexible section.

5. The potting shell as claimed in claim 2, wherein:

the wall thickness in said flexible section amounts to not more than 80% of the wall thickness outside of said flexible section.

6. The potting shell as claimed in claim 1, wherein:

the exterior side of said main wall defines at least one support surface; and

said at least one flexible section is recessed with respect to said support surface.

7. The potting shell as claimed in claim 1, wherein:

said flexible section, in its center, can absorb at least 50% of the thermal expansion of the potting compound perpendicular to the plane of said flexible section.

8. The potting shell as claimed in claim 1, wherein:

said main wall, outside of said flexible section, has at least one opening for electrical feed-throughs; and

said at least one opening is surrounded on the exterior side of the potting shell, and/or on its interior side, by an elastic seal.

9. The potting shell as claimed in claim 8, wherein:

said at least one opening is surrounded on the interior side by a protrusion, which extends from said main wall into the interior of the potting shell; and

said elastic seal is arranged on the protrusion.

10. The potting shell as claimed in claim 8, wherein:

said at least one opening is surrounded on the interior side by a protrusion, which extends from said main wall into the interior of the potting shell; and

said elastic seal is arranged on the protrusion; and

wherein the circuit board presses against said seal on the interior side of the potting shell.

11. The potting shell as claimed in claim 8, wherein:

said at least one opening is surrounded on the interior side by a protrusion, which extends from said main wall into the interior of the potting shell; and

said elastic seal is arranged on the protrusion; and

wherein the circuit board presses against said seal on the interior side of the potting shell.

12. The potting shell as claimed in claim 1, wherein:

the exterior side of said main wall defines at least one support surface; and

said at least one flexible section is recessed with respect to said support surface.

13. The potting shell as claimed in claim 1, wherein:

said flexible section, in its center, can absorb at least 50% of the thermal expansion of the potting compound perpendicular to the plane of said flexible section.

14. The potting shell as claimed in claim 1, wherein:

said main wall, outside of said flexible section, has at least one opening for electrical feed-throughs; and

said at least one opening is surrounded on the exterior side of the potting shell, and/or on its interior side, by an elastic seal;

and wherein the circuit board presses against said seal on the interior side of the potting shell.

15. The potting shell as claimed in claim 1, wherein:

the exterior side of said main wall defines at least one support surface; and

said at least one flexible section is recessed with respect to said support surface.

16. The potting shell as claimed in claim 1, wherein:

said flexible section, in its center, can absorb at least 50% of the thermal expansion of the potting compound perpendicular to the plane of said flexible section.

17. The potting shell as claimed in claim 1, wherein:

said main wall, outside of said flexible section, has at least one opening for electrical feed-throughs; and

said at least one opening is surrounded on the exterior side of the potting shell, and/or on its interior side, by an elastic seal;

and wherein the circuit board presses against said seal on the interior side of the potting shell.

18. An electronics module, comprising:

a populated circuit board, which is arranged in a potting shell, and is potted therein with potting compound;

said potting shell including;

a wall arrangement with a main wall, said wall arrangement defines a shell volume at least in one spatial direction, and in the directions perpendicular thereto, wherein;

the circuit board is positionable in the shell volume, and can be potted in the shell volume with a potting compound;

the volume between the circuit board and a main wall of the potting shell, running essentially parallel, at least sectionally, to the circuit board, can be filled with a potting compound; and

said main wall has at least one flexible section, which, based on a thermal expansion of the potting compound, can be deformed perpendicular to the plane of said flexible section.

19. The electronics module, as claimed in claim 18, wherein:

said flexible section has a lesser wall thickness than other wall sections of the potting shell.

20. The electronics module, as claimed in claim 18, wherein:

said flexible section has a lesser wall thickness than other wall sections of the potting shell.

21. A measuring transmitter for registering a process parameter, comprising:

a housing, in which an electronics module, is arranged which includes;

a wall arrangement with a main wall, said wall arrangement defines a shell volume at least in one spatial direction, and in the directions perpendicular thereto, wherein;

the circuit board is positionable in the shell volume, and can be potted in the shell volume with a potting compound;

the volume between the circuit board and a main wall of the potting shell, running essentially parallel, at least sectionally, to the circuit board, can be filled with a potting compound; and

said main wall has at least one flexible section, which, based on a thermal expansion of the potting compound, can be deformed perpendicular to the plane of said flexible section.

22. The measuring transmitter as claimed in claim 21, wherein the process parameter comprises pressure, pressure difference, fill level, flow rate, temperature, pH-value, redox potential, humidity, turbidity, or gas content in a liquid.