Membrane Unit, Housing Of A Pressure Measuring Unit And Pressure Measuring Unit

• US 20070295093A1
• Filed: 11/10/2005
• Published: 12/27/2007
• Est. Priority Date: 11/17/2004
• Status: Active Grant

• Current Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius SE & Co. KGaA)
• Original Assignee: Fresenius Medical Care Deutschland GmbH (Fresenius SE & Co. KGaA)
• Inventors: Reiter, Reinhold, Caronna, Marco
• Granted Patent: US 7,603,907 B2
• Time in Patent Office: Days
• US Class Current: 73/706
• CPC Class Codes: A61M 1/3639 Blood pressure control, pressure transducers specially adapted therefor
• CPC Class Codes: A61M 1/3641 Pressure isolators
• CPC Class Codes: G01L 19/0023 for flowthrough systems having a flexible pressure transmitting element

Abstract

The present invention relates to a membrane unit adapted for use in a housing of a pressure measuring unit preferably for measuring pressure in an extra-corporal blood circuit comprising a flexible membrane and a fixing ring which is integral with the membrane so that the membrane and the fixing ring form a one-piece element, wherein the fixing ring has a lower flexibility than the membrane and wherein the fixing ring comprises fixing elements for fixing the fixing ring to the pressure measuring housing. The invention further relates to a housing as well as to a pressure measuring unit.

Claims

1. :

Membrane unit adapted for use in a housing (10) of a pressure measuring unit preferably for measuring pressure of blood in an extra-corporeal blood circuit, comprising a flexible membrane (20) and a fixing ring (30) which is integral with the membrane (20) so that the membrane (20) and the fixing ring (30) form a one-piece element, wherein the fixing ring (30) has a lower flexibility than the membrane (20) and wherein the fixing ring (30) comprises one or more fixing elements for fixing the fixing ring (30) to said housing (10).

2. :

Membrane unit according to claim 1, characterized in that the fixing ring (30) and the membrane (20) are linked to each other by means of a suitable connection technique, preferably by means of glueing or welding.

3. :

Membrane unit according to claim 1, characterized in that the fixing ring (30) and the membrane (20) are manufactured jointly in a common process of manufacture.

4. :

Membrane unit according to claim 3, characterized in that the fixing ring (30) and the membrane (20) are manufactured by means of two-component injection moulding.

5. :

Membrane unit according to claim 1, characterized in that the fixing elements of the fixing ring (30) are formed as at least one projection (32), groove or thread.

6. :

Membrane unit according to claim 5, characterized in that the fixing elements of the fixing ring (30) are located at the outside area of the fixing ring (30) and/or that the fixing ring comprises a U-shaped portion, the fixing elements being located at one or both facing sides of the legs of the U-shaped portion.

7. :

Membrane unit according to claim 1, characterized in that the fixing ring (30) is joined perpendicular to the membrane (20).

8. :

Membrane unit according to claim 1, characterized in that the membrane (20) has a circumferential portion and a central portion wherein the circumferential portion has a larger thickness than the central portion.

9. :

Membrane unit according to claim 1, characterized in that the membrane (20) has a circumferentially extending sealing lip (22) for sealing the contact surface between the membrane (20) and said housing (10).

10. :

Membrane unit according to claim 8, characterized in that the sealing lip (22), preferably the sealing lip (22) together with a larger thickness portion in the circumferential portion of the membrane (20) extends into a first direction perpendicular relative to the planar area defined by the central portion of the membrane (20) whereas the fixing ring (30) extends relative to this area into the opposite direction of said first direction.

11. :

Membrane unit according to claim 1, characterized in that the membrane (20) has a groove (24) on the surface facing the fixing ring (30).

12. :

Membrane unit according to claim 1, characterized in that the contact surface (40) between the membrane (20) and the fixing ring (30) is not flat and is preferably provided with one or more projections (42) extending from one of the membrane or the fixing ring (30) which engage with one or more grooves (24) in the other of the membrane (20) and the fixing ring.

13. :

Membrane unit according to claim 9, characterized in that the shape of the sealing lip (22) of the membrane (20) equals the shape of the contact surface (40) between the membrane (20) and the fixing ring (30).

14. :

Housing (10) of a pressure measuring unit, preferably for measuring pressure of blood in an extra-corporeal blood circuit, comprising an inlet (12) and an outlet (14) for a fluid the pressure of which is to be measured as well as a pressure measuring chamber (16) located in fluid communication with the inlet (12) and the outlet (14), wherein the pressure measuring chamber (16) has an opening (17) which is to be closed by a membrane (20) which is to be inserted into the housing (10), wherein the housing (10) further comprises fixing elements for fixing a membrane unit, preferably a membrane unit according to claim 1, to the housing (10) wherein the fixing elements are located at one or more projections (18) extending around said opening (17) of the pressure measuring chamber (16).

15. :

Housing (10) according to claim 14, characterized in that the projections (18) extend perpendicularly relative to said opening (17) of the pressure measuring chamber (16).

16. :

Housing (10) according to claim 12 characterized in that the fixing elements of the projection (18) are formed as groove (19), jut or thread.

17. :

Housing (10) according to claim 14, characterized in that the fixing elements are located on that side of the projection (18) which is oriented to said opening (17) of the pressure measuring chamber (16).

18. :

Pressure measuring unit comprising a membrane unit according to claim 1, wherein the fixing elements of the membrane unit engage with the fixing elements of the housing (10) and wherein the membrane (20) of the membrane unit forms one surface of the pressure measuring chamber (16) of the housing (10).

19. :

Pressure measuring unit comprising housing (10) according to claim 14, wherein the fixing elements of the membrane unit engage with the fixing elements of the housing (10) and wherein the membrane (20) of the membrane unit forms one surface of the pressure measuring chamber (16) of the housing (10).