Honeycomb body with an at least partially ceramic honeycomb structure and a receptacle for a measurement sensor, and process for producing such a honeycomb body

• US 20070266686A1
• Filed: 07/02/2007
• Published: 11/22/2007
• Est. Priority Date: 12/30/2004
• Status: Active Grant

• Current Assignee: Emitec Gesellschaft für Emissionstechnologie mbH (Continental AG)
• Original Assignee: Emitec Gesellschaft für Emissionstechnologie mbH (Continental AG)
• Inventors: Bruck, Rolf
• Granted Patent: US 8,080,081 B2
• Time in Patent Office: Days
• US Class Current: 55/523
• CPC Class Codes: B01J 35/04 Foraminous structures, sieves, grids, honeycombs
• CPC Class Codes: B01J 35/56 Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• CPC Class Codes: F01N 13/008 Mounting or arrangement of exhaust sensors in or on exhaust apparatus sensor arrangements for engine control F02D41/1439
• CPC Class Codes: F01N 2330/38 flow channels with means to enhance flow mixing,(e.g. protrusions or projections)
• CPC Class Codes: F01N 2350/02 Fitting ceramic monoliths in a metallic housing
• CPC Class Codes: F01N 3/2828 Ceramic multi-channel monoliths, e.g. honeycombs
• CPC Class Codes: F01N 3/2853 using mats or gaskets between catalyst body and housing
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Abstract

A honeycomb body, in particular for use in the exhaust system of a motor vehicle, includes an at least partially ceramic honeycomb structure through which a fluid can flow. The honeycomb structure is disposed in a tubular casing and has cavities. The honeycomb body has at least two axial subregions in a longitudinal direction. The honeycomb structure is connected to the tubular casing in an axial securing region and an axial measurement sensor region has a recess for accommodating a measurement sensor in the honeycomb structure. The honeycomb body has a permanent connection between the tubular casing and the ceramic honeycomb structure due to its preferably force-locking and/or form-locking connection between the tubular casing and the honeycomb structure in the securing region. Despite the recess, further damage to the honeycomb structure in the measurement sensor region is avoided. A process for producing such a honeycomb body is also provided.

Claims

1. A honeycomb body, comprising:

a tubular casing;

an at least partially ceramic honeycomb structure through which a fluid can flow, said honeycomb structure being disposed in said tubular casing and said honeycomb structure having cavities;

at least two axial subregions disposed along a longitudinal direction of the honeycomb body, said at least two axial subregions including at least one axial securing region, and at least one axial measurement sensor region;

said honeycomb structure being connected to said tubular casing in said at least one axial securing region; and

said at least one axial measurement sensor region having a recess formed therein for accommodating at least one measurement sensor in said honeycomb structure.

2. The honeycomb body according to claim 1, wherein said at least two axial subregions include an axial sealing region having a seal formed between said honeycomb structure and said tubular casing.

3. The honeycomb body according to claim 2, wherein said measurement sensor region is disposed between said sealing region and said securing region along said longitudinal direction.

4. The honeycomb body according to claim 2, wherein said sealing region is disposed in vicinity of an end side of the honeycomb body.

5. The honeycomb body according to claim 4, wherein said sealing region has a blow-out protector in direction of an end side of the honeycomb body.

6. The honeycomb body according to claim 1, which further comprises at least one connection between said honeycomb structure and said tubular casing being selected from the group consisting of:

a) a force-locking connection;

b) a form-locking connection; and

c) a materially cohesive connection.

7. The honeycomb body according to claim 1, wherein said securing region has axial and circumferential subregions, and a connection between said tubular casing and said honeycomb structure is formed in at least one of said axial and circumferential subregions.

8. The honeycomb body according to claim 1, which further comprises at least one of a flexible or elastic mat disposed at least in a subregion between said honeycomb structure and said tubular casing.

9. The honeycomb body according to claim 1, which further comprises at least one of a swellable mat, a ceramic fiber mat or an intermediate layer of mica disposed at least in a subregion between said honeycomb structure and said tubular casing.

10. The honeycomb body according to claim 1, wherein said tubular casing has a first internal diameter in said securing region and a second internal diameter in said measurement sensor region, and said second internal diameter is larger than said first internal diameter.

11. The honeycomb body according to claim 10, wherein said tubular casing curves convexly outward in at least one of circumferential or axial subregions, at least in said measurement sensor region.

12. The honeycomb body according to claim 1, wherein said measurement sensor region is disposed at a distance of between 20 and 60 mm from an end side of the honeycomb body.

13. The honeycomb body according to claim 1, wherein said measurement sensor region is disposed at a distance of between 30 and 50 mm from an end side of the honeycomb body.

14. The honeycomb body according to claim 1, wherein said measurement sensor region is disposed at a distance of between 35 and 45 mm from an end side of the honeycomb body.

15. A honeycomb body for an exhaust system of a motor vehicle, the honeycomb body comprising:

a tubular casing;

an at least partially ceramic honeycomb structure through which exhaust gas can flow, said honeycomb structure being disposed in said tubular casing and said honeycomb structure having cavities;

at least two axial subregions disposed along a longitudinal direction of the honeycomb body, said at least two axial subregions including at least one axial securing region, and at least one axial measurement sensor region;

said honeycomb structure being connected to said tubular casing in said at least one axial securing region; and

said at least one axial measurement sensor region having a recess formed therein for accommodating at least one exhaust gas measurement sensor in said honeycomb structure.

16. A process for producing a honeycomb body, the process comprising the following steps:

a) providing an at least partially ceramic honeycomb structure through which a fluid can flow and which has at least one recess formed therein for accommodating a measurement sensor;

b) providing a tubular casing having at least one hole formed therein for the measurement sensor to pass through;

c) introducing the honeycomb structure into the tubular casing and joining the honeycomb structure to the tubular casing in at least one axial securing region; and

d) before or during step c), mutually aligning the honeycomb structure and the tubular casing, causing the hole in the tubular casing and the recess in the honeycomb structure to at least partially overlap one another after step c).

17. The process according to claim 16, which further comprises placing an intermediate layer including at least one of the following materials:

a swellable mat,

a ceramic fiber mat,

an intermediate layer of mica,

a porous metallic mat;

an elastic mat, or

a flexible mat,

between the honeycomb structure and the tubular casing.

18. The process according to claim 17, wherein the intermediate layer is spatially inhomogenous.

19. The process according to claim 16, wherein step c) includes joining together at least two tubular casing parts around the honeycomb structure.

20. The process according to claim 16, which further comprises, in step c):

surrounding the honeycomb structure with a compressible mat; and

pressing the honeycomb structure surrounded by the mat into the tubular casing, compressing the mat.

21. The process according to claim 16, which further comprises, in step c), winding the tubular casing in at least one layer around the honeycomb structure.