WO2018019650A1

WO2018019650A1 - Silencer for single-cylinder diesel engine

Info

Publication number: WO2018019650A1
Application number: PCT/EP2017/068077
Authority: WO
Inventors: Tobias Winter; Wolfgang Dorner
Original assignee: Motorenfabrik Hatz Gmbh & Co. Kg
Priority date: 2016-07-26
Filing date: 2017-07-18
Publication date: 2018-02-01
Also published as: US20190170043A1; DE102016113756A1; JP2019523361A; EP3491221B1; EP3491221A1

Abstract

The invention relates to a silencer (1) for single-cylinder diesel engines with an integrated oxidation catalyst, such that the silencer is connected to the cylinder head of the engine, that the silencer housing is divided into two chambers, that is, an inlet chamber and an outlet chamber, by means of an intermediate wall (3) and that the oxidation catalyst (28) is secured in the intermediate wall (3) such that it fludically connects together both chambers.

Description

Silencer for single-cylinder diesel engine

The invention relates to a silencer for a

Single-cylinder diesel engine with oxidation catalyst according to the preamble of claim 1.

Such drives are known. Reference is made to DE 101 39 700 A1 and JP 2015-143 510 A. They are preferably used for operating construction machines or as stationary drives of low power.

The requirements for the cleaning / detoxification of the exhaust gas are different. In many cases, the treatment of the exhaust gas by means of oxidation catalyst, ie the oxidation of the CO components in the exhaust gas to CO ₂ and of hydrocarbons to CO ₂ and water is sufficient.

In the case of retrofitting an oxidation catalyst in an existing single-cylinder diesel engine is

structural mechanics to note that the existing

Muffler is attributed to an oxidation catalyst, without causing the natural frequency of the entire unit is changed while avoiding adverse vibration loads. In this way, it is possible to prevent damage to the working unit connected to the drive unit.

The present invention is therefore based on the object to combine an oxidation catalyst in a suitable manner with a silencer while avoiding the disadvantages mentioned, in particular a reduction in the natural frequency and the associated resonance-related damage.

To achieve this object, the invention provides that the muffler housing is connected by means of a flange directly to the cylinder head, and that the Intermediate wall (3) openings for the gas-tight installation of mounting tubes (14) which traverse the muffler housing and are fixed at their motor-side ends inside a muffler side flange (9) associated with the connecting holes (15), for the purpose

Attaching a screw connection of the connection flange (9) with a corresponding flange part of the cylinder head.

In this way it succeeds, that by the

Oxidation catalyst introduced into the muffler

Add more weight through the partition and distribute it to the entire silencer housing. In this case, the natural frequency of the muffler can be kept within a non-critical range, so that resonance-related damage to the muffler housing or the overall device,

for example, used in the construction industry

Vibratory plates, be avoided.

The use of diesel oxidation catalysts involves the oxidation of carbon monoxide (CO) to carbon dioxide (C0 ₂ ) and of hydrocarbons (C _n H _m ) in the exhaust gas to carbon dioxide (C0 ₂ ) and water. The advantageous for the oxidation high

Exhaust gas temperatures are obtained in the present invention, characterized in that the muffler a

Has flange, by means of which he directly on

Cylinder head can be connected.

In this context, a particularly advantageous embodiment is that the intermediate wall openings for the gas-tight implementation of mounting ears, which traverse the muffler housing and at their

engine-side ends to a silencer side

Connection flange are attached with assignment to the connection holes. A robust and vibration-stable embodiment according to the invention is that the silencer side

Connecting flange is gas-tight welded at its side circumference with a circumferential extent of the muffler housing.

The partition itself is according to the invention gas-tightly secured between two separate housing parts of the muffler housing, namely a motor-facing rear wall and a housing cover. Both housing parts are with the

Welded intermediate wall.

The intermediate wall is advantageously formed cup-shaped with convex bulge against the flowing into the inflow chamber of the muffler exhaust. This results in a

Stiffening of the intermediate wall and thus an improved

Reinforcement of the entire silencer housing.

The catalyst body itself penetrates the intermediate wall in which it is received gas-tight in an opening. The untreated exhaust gas thus flows out of the

Housing rear wall formed inflow through the

Catalyst body through into the separate through the housing cover discharge chamber and from there as aftertreated exhaust gas into the outlet pipe of the engine.

A particularly stable seat of the closed inner end of the outlet tube is inventively achieved in that the intermediate wall has an opening for the gas-tight reception of the inner end of the outlet tube.

For this purpose, in a further advantageous embodiment of the

Mounting the outlet pipe inside the

Muffler housing provided that its inner end protrudes into the inflow chamber of the muffler housing and is slidably supported there in an associated impression of the housing rear wall of the muffler housing.

With the aim of keeping vibrations of the silencer housing as low as possible, the housing itself is on all sides

provided beads and the like embossing forms of

Housing parts provided, which serve not only the stiffening but also the avoidance of resonant vibrations

favor. This purpose is also served by the inventively perforated design of the outlet tube in its section within the outflow chamber of the muffler housing.

An embodiment of the invention will be described below with reference to the drawing. It shows

1 is a sectional view of the muffler according to I-I of Fig. 2,

Fig. 2 is a view against the rear wall of the housing

Silencer with connection flange,

3 is a perspective view of the housing cover with outgoing exhaust pipe,

4 is a sectional view of the muffler according to IV-IV of Fig. 3,

5 shows a variant of a sectional illustration according to FIG. 4, and FIG. 6 shows a perspective view of the rear wall of the housing according to the variant according to FIG. 5.

The figures of the drawings show the muffler housing with housing rear wall 1 and housing cover 2, between which an intermediate wall 3 is fixed. The partition 3

extends gas-tight across the entire

Muffler housing; It is cup-shaped and has a convex bulge in one of the

Housing rear wall 1 formed inflow chamber 4; With its concave side, it thus delimits one from the housing cover 2 formed outflow chamber 5. The intermediate wall 3 has a circumferential bulged connecting edge 6, in which the facing open end 7 of the housing cover 2 enters, so that a gas-tight connection between the two housing parts namely the housing rear wall 1 and the housing cover 2, for example, is ensured by welding.

The catalyst body 28 of an oxidation catalyst

extends from the inlet chamber 4 through the

Through the wall 3, with which it is connected in a gastight manner, in the outlet chamber 5. The exhaust gas from the cylinder head flows through a flange through an on the

Housing rear wall 1 attached flange 9 in the direction of the arrow PI in the interior of the inflow chamber 4 and

from there flows through the catalyst body 28 according to arrow P2. The treated in the catalyst body 28 exhaust gas passes from the catalyst body 28 in the outflow chamber 5 and from there into an outlet pipe 10, 10 'for the treated exhaust gas (see Fig. 4-6). After exiting the catalyst body 28, the treated exhaust gas flows through perforations 11 into the interior of the outlet pipe 10, 10 'and further according to arrow P3, P3' through an exhaust pipe (not shown) into the environment.

As far as the design of the silencer housing is concerned, its housing rear wall 1 and its housing cover 2 are repeatedly stiffened, as indicated by contour lines.

For example, by beads 12 in the region of the rear wall of the housing 1 (Fig. 4) or by inputs / outputs 13, 22 of the

Housing shells, preferably in connection areas with other components. By such embossing molds receive the

Housing parts of the muffler housing a larger

Stiffness, reducing the tendency for housing vibrations

is reduced. It goes without saying that built-in parts of the

Muffler housing which the housing walls or the

Piercing wall in the respective

Opening areas are gas-tight connected to the intermediate wall or the housing walls, including usually

Welded connections are provided. This applies to the

Passage of the catalyst body 28 through the intermediate wall 3, for the passage of the outlet tube 10 through the

Housing cover 2 and the outlet pipe 10 'through the

Housing rear wall 1 (Fig. 5) and also for the passage of the three mounting tubes shown in the embodiment 14 through the rear wall 1, the intermediate wall 3 and the housing cover 2. The three mounting tubes 14 are connected at their motor-side ends fixed to the flange 9, so that through the mounting tubes 14 through the connection holes 15 (Fig. 2) of the connection flange 9 for the mounting tool, which is inserted on the side of the housing cover 2, are accessible. The attachment of the connection flange 9 to a

corresponding (not shown) flange of the

Cylinder head is made by attaching a screw for the production of a tight and tight flange connection

between the muffler housing on the one hand and the

Cylinder block on the other hand. A (not shown)

Flange seal ensures that the untreated exhaust gas from the combustion chamber of the engine passes directly and by the shortest route through the flange bore 16 in the inflow chamber 4 within the housing rear wall 1. Attachment points 17 on the outside of the housing cover 2 and on the outside of the housing rear wall 1 are used to attach a heat plate 18 which is shown in Fig. 1 and 2 schematically drawn as a dashed line. It serves as protection against contact

Burns and extends along the outside of the housing cover 2 and with an angled portion on a narrow side of the muffler housing. In Fig. 4, the closed inner end of the outlet tube 10 is shown. A lid 19 closes the inner end of the outlet tube 10. The end of the outlet tube 10 is

relative to the adjacent housing rear wall 1 in a (not shown) guide supported longitudinally displaceable.

The sectional views according to FIGS. 4 and 5 show similar cross-sections in the plane IV-IV of FIG. 3 through the silencer housing.

In Fig. 4, the outlet pipe 10 extends through the

Housing cover 2 through outward with outflow of purified exhaust gas according to arrow P3.

An alternative solution to this is shown in FIG. 5. Here, the outlet tube 10 'passes through the rear wall 1 of the housing with outflow of the purified exhaust gas according to arrow P3'. Through a perforated pipe section 21 inside the

Outflow chamber 5 passes the cleaned exhaust gas according to arrow P2 'via the outlet pipe 10', which passes through the inflow chamber 4 gas-tight, according to arrow P3 'to the outside.

6 shows a perspective view of the

Silencer housing on the housing cover 2. According to the variant shown in Fig. 5, the outlet pipe 10 'opens through the rear wall 1 to the outside. Incidentally, the muffler housing corresponds to the view shown in Fig. 3, as described there.

Claims

claims

Silencer for single-cylinder diesel engine with

Oxidation catalyst, in silencer housing,

which is connected to the cylinder head of the engine, wherein the silencer housing by an intermediate wall (3) divided into two chambers, and the oxidation catalyst (28) in the intermediate wall (3) is fixed, such that it connects both chambers fluidly with each other and wherein one of Intermediate wall (3) in the flow direction downstream outflow chamber (5) of the muffler is gas-tightly connected to an outlet pipe (10) for the aftertreated exhaust gas,

characterized,

that the muffler housing by means of a

Flange connection is connected directly to the cylinder head, and that the intermediate wall (3) has openings for the gas-tight installation of mounting tubes (14), which traverse the silencer housing and at their

the motor-side ends on the inside of a silencer-side connecting flange (9) with assignment to the

Connection holes (15) are fixed in order

Silencer according to claim 1,

characterized,

the silencer-side connection flange (9) is welded gas-tight on its side circumference to a form (22) of the silencer housing circulating thereon.

Silencer according to claim 1,

characterized,

that the intermediate wall (3) gas-tight between two

Housing parts of the muffler housing is attached. Silencer according to claim 1,

characterized,

the intermediate wall (3) has an opening for the gastight passage of the catalyst body (28).

Silencer according to claim 1,

characterized,

that the intermediate wall (3) has an opening for the gas-tight reception of the closed inner end of the outlet pipe (10).

Silencer according to claim 5,

characterized,

in that the inner end of the outlet tube (10) projects into an inflow chamber (4) of the silencer housing upstream of the intermediate wall (3) and is displaceably supported there in an associated impression of the housing rear wall (1) of the silencer housing.

Silencer according to claim 1,

characterized,

that the outlet pipe (10) in its portion within the outflow chamber (5) of the muffler housing

perforated is formed.

Silencer according to claim 1,

characterized,

in that the intermediate wall (3) is in the shape of a dish with a convex protrusion against the inlet chamber (4) of the

Silencer incoming exhaust gas is formed.