Pressure sensor module and method for manufacturing the same

• US 20090255344A1
• Filed: 04/07/2009
• Published: 10/15/2009
• Est. Priority Date: 04/09/2008
• Status: Active Grant

• Current Assignee: Hella KGaA Hueck & Company
• Original Assignee: Hella KGaA Hueck & Company
• Inventors: Niemann, Thomas, Stuermann, Joerg
• Granted Patent: US 7,798,008 B2
• Time in Patent Office: Days
• US Class Current: 73/754
• CPC Class Codes: G01L 19/141 Monolithic housings, e.g. molded or one-piece housings
• CPC Class Codes: G01L 19/148 Details about the circuit board integration, e.g. integrated with the diaphragm surface or encapsulation
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48137 the bodies being arranged next to each other, e.g. on a common substrate
• CPC Class Codes: H01L 2924/00014 the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details

Abstract

For a pressure sensor module comprising a printed circuit board and a pressure cell, wherein the pressure cell has a measuring opening, and the pressure cell is encapsulated by injection molding compound in such a manner that the measuring opening is kept open, the pressure cell, as viewed from the measuring opening, is attached on the rear side of the printed circuit board. The printed circuit board has a recess in the area of the measuring opening, and the injection molding compound encloses the attachment area of the pressure cell on the printed circuit board. Thereby, the use of different adhesives, also soft adhesives, for the connection of the pressure cell with the printed circuit board is possible without this attachment area being attacked by the surrounding media.

Claims

1. A pressure sensor module comprising a printed circuit board (1) and a pressure cell (4), wherein the pressure cell (4) has a measuring opening (6) and the pressure cell (4) is encapsulated with injection molding compound (8) in such a manner that the measuring opening (6) of the pressure cell (4) is left open,

wherein the pressure cell (4), as viewed from the measuring direction (11), is attached on the rear side of the printed circuit board (1),

wherein the printed circuit board (1) has a recess (7) in the area of the measuring opening (6), and

wherein the injection molding compound (8) encloses the attachment area (10) of the pressure cell (4) on the printed circuit board (1).

2. The pressure sensor module according to claim 1,

wherein the pressure cell (4) is glued to the printed circuit board (1).

3. The pressure sensor module according to claim 1,

wherein the printed circuit board (1) has a recess (7) in the area of the pressure cell (4) which is bigger than the measuring opening (6) of the pressure cell (4).

4. The pressure sensor module according to claim 1,

wherein the printed circuit board (1) has a recess (7) in the area of the pressure cell (4), the diameter of which recess is at least double the size of the diameter of the measuring opening (6) of the pressure cell (4).

5. The pressure sensor module according to claim 1,

wherein the injection molding compound (8) is directly injection-molded on the pressure cell (4).

6. The pressure sensor module according to claim 1,

wherein the portion (9) of the measuring opening (6) formed in the injection molding compound (8) is formed funnel-shaped.

8. A motor vehicle comprising a pressure sensor module according to claim 1.

9. A method for manufacturing a pressure sensor module according to claim 1, in which before the encapsulation with injection molding compound, a stamp is placed on the area to be kept free,

wherein the stamp is placed directly onto the pressure cell, wherein the stamp is dimensioned and positioned in such a manner that around the area on the pressure cell covered by the stamp, a free area remains on the pressure cell, to which area, injection molding compound is applied in the subsequent step.

7. A pressure sensor module comprising a printed circuit board (1) and a pressure cell (4), wherein the pressure cell (4) has a measuring opening (6) and the pressure cell (4) is encapsulated with injection molding compound (8) in such a manner that the measuring opening (6) of the pressure cell (4) is left open,

wherein the pressure cell (4), as viewed from the measuring direction (11), is attached on the rear side of the printed circuit board (1),

wherein the printed circuit board (1) has a recess (7) in the area of the pressure cell (4), the diameter of which recess is at least double the size of the diameter of the measuring opening (6) of the pressure cell (4), and

wherein the injection molding compound (8) encloses the attachment area (10) of the pressure cell (4) on the printed circuit board (1).