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US5606856A Expired / Lapsed US ⏱️ 0.0 years remaining

Arrangement for an after treatment of exhaust gases from an internal combustion engine

Assignee: Robert Bosch GmbH
•
Filing: 1995-11-17
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Granted: 1997-03-04
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Expires: 2015-11-17
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Abstract

Abstract To reduce NO x components in the exhaust gas from a compression-ignition internal combustion engine with the aid of a reducing catalytic converter, a metering device for the supply of reducing agent to be additionally introduced into the exhaust gas, in the form of fuel, is provided to improve the performance of the catalytic converter. For this purpose, use is made of a positive displacement pump designed to meter very small quantities with a helix in the form of a helical groove arranged on a cylindrical body of revolution, the delivery rate being varied by driving the body of revolution at a variable rotational speed.

Inventors

  • 👤 Ernst Linder
  • 👤 Hubert Dettling

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 12:59
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/24; F01N3/36; B; B01; B01D; B01D53/00; B01D53/34; B01D53/92; B01D53/94; B01D53/9404; B01D53/9409; B01D53/9431; B01D53/9495; F01N3/18; F01N3/20; F01N3/2006; F01N3/2033; F01N3/206; F01N3/2066; F01N3/30; F01N3/306; F01N2240/00; F01N2240/14; F01N2610/00; F01N2610/03; F01N2610/08; F01N2610/10; F01N2610/107; F01N2610/14; F01N2610/1433; F01N2610/1453; F01N3/22; F01N3/32; F02; F02B; F02B1/00; F02B1/02; F02B1/04; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12

Claims Analysis

Total Claims: 24
Claim 1
Independent Claim 156 words
An arrangement for an after-treatment of exhaust gases from a compression-ignition internal combustion engine, in an exhaust-gas collecting system (3) of which a reducing catalytic converter (5) for reducing NO x components of the exhaust gas from the internal combustion engine is arranged, a metering device (12) controlled by a control device (9) and serving for the metered introduction of a reducing agent into the stream of exhaust gas fed to the catalytic converter as a function of values, stored in a characteristic map, for the NO x content of the exhaust gas given various operating parameters of the internal combustion engine and of the catalytic converter, and with an air feed pump arranged upstream of the metering device and serving for the finely dispersed preparation of the reducing agent to be introduced, the metering device (12) comprises a continuous-delivery positive displacement pump (14) driven at a variable rotational speeds controlled by the control device (9).
Claim 2
Dependent Claim 156 words
An arrangement for an after-treatment of exhaust gases from a compression-ignition internal combustion engine, in an exhaust-gas collecting system (3) of which a reducing catalytic converter (5) for reducing NO x components of the exhaust gas from the internal combustion engine is arranged, a metering device (12) controlled by a control device (9) and serving for the metered introduction of a reducing agent into the stream of exhaust gas fed to the catalytic converter as a function of values, stored in a characteristic map, for the NO x content of the exhaust gas given various operating parameters of the internal combustion engine and of the catalytic converter, and with an air feed pump arranged upstream of the metering device and serving for the finely dispersed preparation of the reducing agent to be introduced, the metering device (12) comprises a continuous-delivery positive displacement pump (14) driven at a variable rotational speeds controlled by the control device (9).
Claim 3
Dependent Claim 88 words
An arrangement according to claim 1, in which the positive displacement pump (14) has a cylindrical body of revolution (38) which is mounted in a cylinder (46), is driven by an electric motor (43) and, on a curved surface, has at least one helix (47), which leads from a reducing-agent inlet opening (44) into the cylinder as far as a reducing-gent outlet opening (45) out of the cylinder (46), which reducing-agent outlet opening is connected to a reducing-agent introduction point (22) at the inlet of the catalytic converter.
Claim 4
Dependent Claim 84 words
An arrangement according to claim 2, in which the reducing agent is pumped by the positive displacement pump (14) into a swirl chamber (16) into which an additional air flow delivered by an air pump (20) is introduced tangentially, and the reducing agent is pumped via a line (17) entering perpendicularly to the introduced air flow into the swirl chamber (16), from which a discharge tube (22) with a plurality of outlet openings (25) leads into the exhaust-gas stream as a reducing-agent introduction point.
Claim 5
Dependent Claim 23 words
An arrangement according to claim 3, in which the swirl chamber (16) is in thermally conductive connection with the exhaust-gas collecting system (3).
Claim 6
Dependent Claim 47 words
An arrangement according to claim 2, in which the positive displacement pump (14) is controlled by the control device (9) that it is operated in the temperature range of the exhaust gas in the catalytic converter between 200°-400° C. during the operation of the internal combustion engine.
Claim 7
Dependent Claim 60 words
An arrangement according to claim 3, in which the discharge tube is of U-shaped design with a first arm (23) situated in an upstream position transversely to the exhaust-gas stream and branching off axially from the swirl chamber and with a second arm (24), which is closed at the end and has the outlet openings (25) in its lateral surface.
Claim 8
Dependent Claim 23 words
An arrangement according to claim 6, in which the outlet openings (25) are arranged on a downstream side of the second arm (24).
Claim 9
Dependent Claim 84 words
An arrangement according to claim 1, in which the reducing agent is pumped by the positive displacement pump (14) into a swirl chamber (16) into which an additional air flow delivered by an air pump (20) is introduced tangentially, and the reducing agent is pumped via a line (17) entering perpendicularly to the introduced air flow into the swirl chamber (16), from which a discharge tube (22) with a plurality of outlet openings (25) leads into the exhaust-gas stream as a reducing-agent introduction point.
Claim 10
Dependent Claim 23 words
An arrangement according to claim 8, in which the swirl chamber (16) is in thermally conductive connection with the exhaust-gas collecting system (3).
Claim 11
Dependent Claim 60 words
An arrangement according to claim 8, in which the discharge tube is of U-shaped design with a first arm (23) situated in an upstream position transversely to the exhaust-gas stream and branching off axially from the swirl chamber and with a second arm (24), which is closed at the end and has the outlet openings (25) in its lateral surface.
Claim 12
Dependent Claim 23 words
An arrangement according to claim 10, in which the outlet openings (25) are arranged on a downstream side of the second arm (24).
Claim 13
Dependent Claim 47 words
An arrangement according to claim 11, in which the positive displacement pump (14) is controlled by the control device (9) that it is operated in the temperature range of the exhaust gas in the catalytic converter between 200°-400° C. during the operation of the internal combustion engine.
Claim 14
Dependent Claim 47 words
An arrangement according to claim 9, in which the positive displacement pump (14) is controlled by the control device (9) that it is operated in the temperature range of the exhaust gas in the catalytic converter between 200°-400° C. during the operation of the internal combustion engine.
Claim 15
Dependent Claim 47 words
An arrangement according to claim 10, in which the positive displacement pump (14) is controlled by the control device (9) that it is operated in the temperature range of the exhaust gas in the catalytic converter between 200°-400° C. during the operation of the internal combustion engine.
Claim 16
Dependent Claim 47 words
An arrangement according to claim 8, in which the positive displacement pump (14) is controlled by the control device (9) that it is operated in the temperature range of the exhaust gas in the catalytic converter between 200°-400° C. during the operation of the internal combustion engine.
Claim 17
Dependent Claim 47 words
An arrangement according to claim 1, in which the positive displacement pump (14) is controlled by the control device (9) that it is operated in the temperature range of the exhaust gas in the catalytic converter between 200°-400° C. during the operation of the internal combustion engine.
Claim 18
Dependent Claim 36 words
An arrangement according to claim 16, in which the air pump is likewise controlled as a function of operating parameters of the internal combustion engine, in accordance with an introduction of quantities of a reducing agent.
Claim 19
Dependent Claim 28 words
An arrangement according to claim 1, in which when the internal combustion engine is switched off, the air feed pump continues to be operated for a certain time.
Claim 20
Dependent Claim 82 words
An arrangement according to claim 1, in which a combustion device (11) controlled in a combustion rate as a function of operating parameters of the internal combustion engine, including the temperature one of of the exhaust gas and of the reducing catalytic converter, by means of which fuel together with air is burnt, and the exhaust gases from this combustion device are fed to the exhaust gas of the internal combustion engine upstream of the introduction point (22) for the reducing agent.
Claim 21
Dependent Claim 25 words
An arrangement according to claim 19, in which the air pump (20) at the same time also supplies the combustion device (11) with compressed air.
Claim 22
Dependent Claim 18 words
An arrangement according to claim 20, in which the device for reoxidation is an oxidizing catalytic converter (6).
Claim 23
Dependent Claim 29 words
An arrangement according to claim 1, in which an oxidizing device (6) for reoxidizing the exhaust gas is provided in the exhaust-gas collecting system downstream of the catalytic converter.
Claim 24
Dependent Claim 25 words
An arrangement according to claim 1, in which fuel is used as the reducing agent, and the combustion device is likewise operated with this fuel.

References Cited (Backward Citations)

US4403473A Cited
US4576617A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-03-03 2000-09-02 2001-03-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-03-03 2004-09-02 2005-03-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-03-03 2008-09-02 2009-03-04 $7700.00 Window Closed / Lapsed

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