Exhaust device with a flame resonator

Abstract

The present invention relates to an exhaust device for internal-combustion-engine-driven small appliances. The exhaust device includes a housing which has at least one exhaust inlet opening and at least one exhaust outlet opening, and a flame resonator for suppressing flames emerging from the exhaust device. The flame resonator is arranged inside the housing and is configured as a channel-like resonator cavity into which the exhaust gas flows at least partly, whereby flames emerging from the housing can be avoided in the exhaust gas.

1 . An exhaust device for internal-combustion-engine-driven small appliances, comprising: a housing which has at least one exhaust inlet opening, at least one exhaust outlet opening, and a flame resonator for suppressing flames emerging from the exhaust device, characterised in that the flame resonator is arranged inside the housing and is configured as a channel-like resonator cavity into which the exhaust gas flows at least partly, whereby flames emerging from the housing can be avoided in the exhaust gas. 
   
   
       2 . The exhaust device according to  claim 1 , characterised in that the housing comprises at least one rear shell and a front shell, which are brought together such that the insides of the shells lie opposite to one another to form the housing. 
   
   
       3 . The exhaust device according to  claim 2 , characterised in that an intermediate shell is arranged between the rear shell and the front shell. 
   
   
       4 . The exhaust device according to  claim 3 , characterised in that a first partial volume between the intermediate shell and the rear shell forms the channel-like resonator cavity, having an an opening in one direction only. 
   
   
       5 . The exhaust device according to  claim 4 , characterised in that a first partial volume between the intermediate shell and the front shell forms the channel-like resonator cavity. 
   
   
       6 . The exhaust device according to  claim 5 , characterised in that the exhaust device comprises a catalyst which is arranged inside the housing. 
   
   
       7 . The exhaust device according to  claim 6 , characterised in that the exhaust gas flows through the catalyst into the volume behind the rear shell and the intermediate shell. 
   
   
       8 . The exhaust device according to  claim 7 , characterised in that after leaving the catalyst, the exhaust gas flows in a type of bifurcation either into the first partial volume forming the channel-like resonator cavity or into a second partial volume. 
   
   
       9 . The exhaust device according to  claim 8 , characterised in that the exhaust gas reaches the exhaust outlet opening through the second partial volume. 
   
   
       10 . The exhaust device according to  claim 8 , characterised in that the exhaust device can be divided by a median line which runs geometrically centrally over the housing, wherein the geometrical configuration of the first partial volume and the second partial volume is approximately symmetrical and extends on each side of the median line. 
   
   
       11 . The exhaust device according to  claim 10 , characterised in that the catalyst is cylindrical and is arranged centrally on the median line between the front shell and the intermediate shell or between the rear shell and the intermediate shell. 
   
   
       12 . The exhaust device according to  claim 10 , characterised in that an insulating shell is provided between the rear shell and the intermediate shell which runs approximately at the same distance from a geometrical formation of the rear shell to form an insulating gap. 
   
   
       13 . The exhaust device according to  claim 11 , characterised in that the insulating shell is arranged between the front shell and the intermediate shell, and runs approximately at the same distance from a geometrical formation of the front shell to form an insulating gap. 
   
   
       14 . The exhaust device according to  claim 12 , characterised in that an insulating compound, in particular glass fibre insulation is incorporated in the insulating gap. 
   
   
       15 . The exhaust device according to  claim 12 , characterised in that the rear shell, the insulating shell and the intermediate shell have a respective opening which jointly form the exhaust inlet opening. 
   
   
       16 . The exhaust device according to  claim 12 , characterised in that the intermediate shell comprises a cup-shaped inner contour with a cup base and said cup base abuts in a plane-parallel manner against the insulating shell. 
   
   
       17 . The exhaust device according to  claim 16 , characterised in that the separation of the first partial volume and the second partial volume is formed by the cup-shaped inner contour of the intermediate shell. 
   
   
       18 . The exhaust device according to  claim 13 , characterised in that a spacer sheet is arranged between the rear shell and the insulating shell in the area of the exhaust inlet opening, wherein the spacer sheet has a thickness according to the insulating gap. 
   
   
       19 . The exhaust device according to  claim 17 , characterised in that a silencer element can be accommodated in the cup-shaped inner contour. 
   
   
       20 . A hand-held work machine, in particular chain saw, hedge trimmer, rotary mower or the like, comprising an internal combustion engine and an exhaust device ( 100 ) according to  claim 1 .