US-12618350-B2 - Mixer arrangement for mixing an injection medium injectable by an injector with the exhaust gas of an internal combustion engine

US12618350B2US 12618350 B2US12618350 B2US 12618350B2US-12618350-B2

Abstract

A mixer arrangement for mixing an injection medium injectable by an injector with the exhaust gas of an internal combustion engine, includes a first exhaust gas guide section and a second exhaust gas guide section, through each of which the exhaust gas of the internal combustion engine can be guided, and a mixing pipe which fluidically connects the first exhaust gas guide section to the second exhaust gas guide section. The mixing pipe has an opening, through which the injection medium from the injector can be injected into the mixing pipe. A sleeve element surrounds the mixing pipe at least in sections, so that a gap is formed between the sleeve element and the mixing pipe. The gap is fluidically connected to the first exhaust gas guide section.

Inventors

Adrian Troeger

Assignees

DEUTZ AKTIENGESELLSCHAFT
DEERE & COMPANY

Dates

Publication Date: 20260505
Application Date: 20240919
Priority Date: 20230922

Claims (9)

1 . A mixer arrangement for mixing an injection medium injectable by an injector with exhaust gas of an internal combustion engine, comprising: a first exhaust gas guide section and a second exhaust gas guide section, through each of which the exhaust gas from the internal combustion engine is guidable; a mixing pipe fluidically connecting the first exhaust gas guide section to the second exhaust gas guide section, wherein the mixing pipe has an opening through which the injection medium is injectable from the injector into the mixing pipe; and a sleeve element surrounding the mixing pipe at least partially, so that a gap is formed between the sleeve element and the mixing pipe, wherein the gap is fluidically connected to the first exhaust gas guide section, the mixing pipe being longer than the sleeve element, wherein the sleeve element has contact sections with which the sleeve element is seated on the mixing pipe, the sleeve element being in contact with the mixing pipe only with the contact sections, wherein the contact sections are designed as a plurality of spring tabs.
2 . The mixer arrangement according to claim 1 wherein the mixing pipe comprises a cylinder section, and wherein the sleeve element comprises a cylinder section that surrounds the cylinder section of the mixing pipe at least partially.
3 . The mixer arrangement according to claim 1 , wherein the gap between the mixing pipe and the sleeve element is a closed annular gap.
4 . The mixer arrangement according to claim 1 , wherein the gap is fluidically connected to the second exhaust gas guide section directly and/or via the mixing pipe.
5 . The mixer arrangement according to claim 1 , wherein a first spring tab of said plurality of spring tabs is arranged at a first axial end of the sleeve element.
6 . The mixer arrangement according to claim 1 , wherein the sleeve element is connected to the first exhaust gas guide section via a first thermally insulating insulation arrangement, and/or wherein the sleeve element is connected to the second exhaust gas guide section via a second thermally insulating insulation arrangement.
7 . The mixer arrangement according to claim 1 , wherein the spring tabs are formed integrally with the sleeve element and are bent inward from the sleeve element.
8 . The mixer arrangement according to claim 5 , wherein the first spring tab forms an axial endpoint of the sleeve element.
9 . The mixer arrangement according to claim 8 , wherein a second spring tab of said plurality of spring tabs is arranged at an opposite second axial end of the sleeve element wherein the second spring tab forms a further axial endpoint of the sleeve element.

Description

CROSS REFERENCE TO RELATED APPLICATION This claims the benefit of a German Patent Application DE 102023125729.3, filed on Sep. 22, 2023, which is hereby incorporated by reference herein. TECHNICAL FIELD The present disclosure relates to a mixer arrangement for mixing an injection medium injectable by an injector with the exhaust gas of an internal combustion engine. BACKGROUND Reactants are introduced into the exhaust gas flow for the after-treatment of exhaust gases, so that environmentally harmful components in the exhaust gas are reduced. In diesel internal combustion engines, for example, a urea-water solution is injected into the exhaust gas in order to reduce the proportion of nitrogen oxide in the exhaust gas in a downstream SCR catalytic converter arrangement. A mixer arrangement can be arranged upstream of the catalytic converter arrangement, which mixes the reactant injected into the exhaust gas flow with the exhaust gas in order to improve the effectiveness of the catalytic converter. A mixer arrangement for an internal combustion engine is known from EP 3 808 949 A1, comprising: a base element, wherein a reactant input opening is formed in the base element, which is open in the direction of a radially expanding reactant receiving volume, and a swirl generating element connected to the base element, wherein a mixing volume adjoining the reactant receiving volume is formed in the swirl generating element and a plurality of exhaust gas passage openings following one another in the circumferential direction is provided in the swirl generating element. A plurality of exhaust gas passage channels are provided in the base element, which are arranged in succession in the circumferential direction and are open to the reactant intake volume. The arrangement is intended to reduce the risk of deposits forming on the reactant and improve mixing behavior. SUMMARY An object of the present disclosure is to provide a mixer arrangement for mixing an injection medium injectable by an injector with the exhaust gas of an internal combustion engine, which minimizes the deposition of the injection medium in the mixer arrangement in a simple manner. To achieve an object, a mixer arrangement is proposed for mixing an injection medium injectable by an injector with the exhaust gas of an internal combustion engine, comprising: a first exhaust gas guide section and a second exhaust gas guide section, through each of which the exhaust gas of the internal combustion engine can be guided, a mixing pipe which fluidically connects the first exhaust gas guide section to the second exhaust gas guide section, the mixing pipe having an opening through which the injection medium can be injected from the injector into the mixing pipe. A sleeve element is also provided, which surrounds the mixing pipe at least partially, so that a gap is formed between the sleeve element and the mixing pipe, the gap being fluidically connected to the first exhaust gas guide section. The advantage of the mixer arrangement is that the exhaust gas can enter the gap between the mixing pipe and the sleeve element without the injection medium being mixed in, where it can effectively transfer the thermal energy contained in the exhaust gas to the mixing pipe. The mixing pipe is heated evenly due to the continuous flow of hot exhaust gas around it and local cold spots on the inner wall of the mixing pipe, where liquid injection medium can crystallize and deposit, are avoided. In a possible embodiment, the mixing pipe can comprise a cylinder section. The sleeve element can comprise a cylinder section. The cylinder section of the sleeve element can surround the cylinder section of the mixing pipe, at least partially. The gap can be designed as a narrow, elongated opening forming an intermediate space between the mixing pipe and the sleeve element. The gap between the mixing pipe and the sleeve element can be designed as a closed annular gap, at least partially. The gap can be fluidically connected to the second exhaust gas guide section. Alternatively, or in combination, the gap can be fluidically connected to the second exhaust gas guide section via the mixing pipe. In a possible embodiment, the sleeve element can have contact sections with which the sleeve element is seated on the mixing pipe. The sleeve element can only be in contact with the mixing pipe with the contact sections. In particular, the contact sections can be designed as spring tabs. A first spring tab can be arranged at a first axial end of the sleeve element. Alternatively or in combination, a second spring tab can be arranged at an opposite second axial end of the sleeve element. In a further possible embodiment, the mixing pipe can have at least one cutout via which the first exhaust gas guide section is fluidically connected to the gap. BRIEF SUMMARY OF THE DRAWINGS In the following, an embodiment of a mixer arrangement is explained in more detail with reference to the figures. Herein FIG.