Patent US5560200A successfully refreshed from Google Patents.
US5560200A
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Method and apparatus for functional monitoring of a catalytic converter
Assignee: EMITED GESELLSCHAFT fur EMISSIONSTECHNOLOGIE MBH
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Filing: 1995-06-07
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Granted: 1996-10-01
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Expires: 2015-06-07
Abstract
Abstract A catalytic converter has a carrier structure and a catalytically active coating adhering to the carrier structure, and is disposed downstream of an internal combustion engine of a motor vehicle for cleaning exhaust gas. A method for functional monitoring of the catalytic converter includes determining a temperature of the catalytically active coating and/or of the structure of the catalytic converter at least at one location. A temperature of the exhaust gas is determined upstream of the at least one location of the catalytic converter. At least first derivatives over time of both temperature values are formed. A difference of the derivatives over time is formed. An instant after a start of the engine at which the difference changes its sign is ascertained. An apparatus for functional monitoring of the catalytic converter includes at least one measuring sensor for measuring a temperature of the carrier structure and/or of the catalytically active coating. At least one device determines an exhaust gas temperature. A differentiation circuit forms derivatives over time of the measured or determined temperatures. A subtraction circuit forms a difference between the two derivatives over time. A comparison circuit ascertains an instant at which the difference changes its sign.
Inventors
- 👤 Wolfgang Maus
- 👤 Helmut Swars
- 👤 Rolf Bruck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:50
CPC Classifications
F; F01; F01N; F01N11/00; F01N11/002; F01N9/00; F01N2550/00; F01N2550/02; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/40
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
125 words
A method for functional monitoring of a catalytic converter, having a carrier structure and a catalytically active coating adhering to the carrier structure, and being disposed downstream of an internal combustion engine of a motor vehicle for cleaning exhaust gas, which comprises: a. determining a temperature of at least one of the catalytically active coating and the structure of the catalytic converter at least at one location; b. determining a temperature of the exhaust gas upstream of the at least one location of the catalytic converter; c. forming at least first derivatives over time of both temperature values; d. forming a difference of the derivatives over time; and e. ascertaining an instant after a start of the engine at which the difference changes its sign.
Claim 2
Independent Claim
125 words
A method for functional monitoring of a catalytic converter, having a carrier structure and a catalytically active coating adhering to the carrier structure, and being disposed downstream of an internal combustion engine of a motor vehicle for cleaning exhaust gas, which comprises: a. determining a temperature of at least one of the catalytically active coating and the structure of the catalytic converter at least at one location; b. determining a temperature of the exhaust gas upstream of the at least one location of the catalytic converter; c. forming at least first derivatives over time of both temperature values; d. forming a difference of the derivatives over time; and e. ascertaining an instant after a start of the engine at which the difference changes its sign.
Claim 3
Dependent Claim
34 words
The method according to claim 1, which comprises measuring the temperature of at least one of the catalytically active coating and the carrier structure at the instant at which the difference changes its sign.
Claim 4
Dependent Claim
36 words
The method according to claim 1, which comprises directly measuring the temperature of the carrier structure of the catalytic converter with at least one measuring sensor being integrated at the carrier structure of the catalytic converter.
Claim 5
Dependent Claim
23 words
The method according to claim 3, which comprises integrating the at least one measuring sensor onto the carrier structure of the catalytic converter.
Claim 6
Dependent Claim
23 words
The method according to claim 3, which comprises integrating the at least one measuring sensor into the carrier structure of the catalytic converter.
Claim 7
Dependent Claim
34 words
The method according to claim 3, which comprises integrally measuring over at least a portion of at least one of the cross section and the length of the catalytic converter with the measuring sensor.
Claim 8
Dependent Claim
34 words
The method according to claim 1, which comprises directly measuring the temperature of the exhaust gas with at least one measuring sensor in an exhaust gas stream between the engine and the catalytic converter.
Claim 9
Dependent Claim
26 words
The method according to claim 1, which comprises determining the temperature of the exhaust gas from various measured values being measured anyway for controlling the engine.
Claim 10
Dependent Claim
29 words
The method according to claim 8, which comprises determining the temperature of the exhaust gas from the temperature of the engine, rpm, and quantities of air and fuel supplied.
Claim 11
Dependent Claim
35 words
The method according to claim 1, which comprises determining an absolute magnitude of the difference among the derivatives over time under fixed, known operating conditions and monitoring the absolute magnitude for deviations from command values.
Claim 12
Dependent Claim
40 words
The method according to claim 1, which comprises measuring at least one of the temperature of the carrier structure and the catalytically active coating of the catalytic converter integrally over a length of a first portion of the catalytic converter.
Claim 13
Dependent Claim
21 words
The method according to claim 1, which comprises measuring the temperature approximately representatively over a cross-sectional region of the catalytic converter.
Claim 14
Dependent Claim
32 words
The method according to claim 1, which comprises measuring the temperature approximately representatively over a cross-sectional region within a first 3 to 10 cm inside the carrier structure of the catalytic converter.
Claim 15
Dependent Claim
30 words
The method according to claim 3, which comprises recalibrating the at least one measuring sensor from time to time after the engine has been off for a relatively long period.
Claim 16
Dependent Claim
40 words
The method according to claim 3, which comprises recalibrating the at least one measuring sensor from time to time after the engine has been off for a relatively long period, by comparison with an ambient temperature sensor and suitable recalibration.
Claim 17
Dependent Claim
43 words
The method according to claim 3, which comprises recalibrating the at least one measuring sensor from time to time after the engine has been off for a relatively long period, by comparison with a coolant sensor of the motor vehicle and suitable recalibration.
Claim 18
Dependent Claim
30 words
The method according to claim 7, which comprises recalibrating the at least one measuring sensor from time to time after the engine has been off for a relatively long period.
Claim 19
Dependent Claim
40 words
The method according to claim 7, which comprises recalibrating the at least one measuring sensor from time to time after the engine has been off for a relatively long period, by comparison with an ambient temperature sensor and suitable recalibration.
Claim 20
Dependent Claim
43 words
The method according to claim 7, which comprises recalibrating the at least one measuring sensor from time to time after the engine has been off for a relatively long period, by comparison with a coolant sensor of the motor vehicle and suitable recalibration.
Claim 21
Dependent Claim
148 words
In an apparatus for functional monitoring of a catalytic converter, having a carrier structure and a catalytically active coating adhering to the carrier structure, and being disposed downstream of an internal combustion engine of a motor vehicle for cleaning exhaust gas, the improvement comprising: a. at least one measuring sensor for measuring a temperature of at least one of the carrier structure and the catalytically active coating; b. at least one device for determining an exhaust gas temperature; c. a differentiation circuit connected to said at least one measuring sensor and to said at least one device, for forming derivatives over time of the measured and determined temperatures; d. a subtraction circuit connected to said differentiation circuit for forming a difference between the two derivatives over time; and e. a comparison circuit connected to said subtraction circuit for ascertaining an instant at which the difference changes its sign.
Claim 22
Dependent Claim
148 words
In an apparatus for functional monitoring of a catalytic converter, having a carrier structure and a catalytically active coating adhering to the carrier structure, and being disposed downstream of an internal combustion engine of a motor vehicle for cleaning exhaust gas, the improvement comprising: a. at least one measuring sensor for measuring a temperature of at least one of the carrier structure and the catalytically active coating; b. at least one device for determining an exhaust gas temperature; c. a differentiation circuit connected to said at least one measuring sensor and to said at least one device, for forming derivatives over time of the measured and determined temperatures; d. a subtraction circuit connected to said differentiation circuit for forming a difference between the two derivatives over time; and e. a comparison circuit connected to said subtraction circuit for ascertaining an instant at which the difference changes its sign.
Claim 23
Dependent Claim
44 words
The apparatus according to claim 20, including a memory device connected to said comparison circuit for storing a measured temperature value of at least one of the catalytically active coating and the carrier structure at the instant at which the difference changes its sign.
Claim 24
Dependent Claim
41 words
The apparatus according to claim 21, including another memory device connected to said comparison circuit for storing at least one of command values and earlier-measured values of the measured temperature value at the instant at which the difference changes its sign.
Claim 25
Dependent Claim
118 words
The apparatus according to claim 20, including: a comparison device connected to said comparison circuit; a first memory device connected to said comparison device for storing a measured temperature value of at least one of the catalytically active coating and the carrier structure at the instant at which the difference changes its sign; and a second memory device connected to said comparison device for storing at least one of command values and earlier-measured values of the measured temperature value at the instant at which the difference changes its sign; said comparison device comparing the measured temperature value at the instant at which the difference changes its sign with at least one of the command values and earlier-measured values.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-10-01 | 2000-04-01 | 2000-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-01 | 2004-04-01 | 2004-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-01 | 2008-04-01 | 2008-10-01 | $7700.00 | Window Closed / Lapsed |