Silencer insert, silencer comprising the same and method for manufacturing a silencer insert

Abstract

A silencer insert (10) for a silencer of an exhaust system includes a first and a second partition wall (11, 12) and a connecting wall (13) arranged therebetween. The first partition wall (11) defines a first plane (E1), the second partition wall (12) defines a second plane (E2), and the connecting wall (13) defines a third plane (E3). At least one of the first partition wall, the second partition wall, and the connecting wall includes at least one perforated area (15). The connecting wall (13) is formed in one piece with the first partition wall (11) and the second partition wall (12). The first plane encloses with the second plane an angle of not more than 60°, the first plane and the second plane being particularly in parallel. A silencer is provided including a housing (1) receiving the silencer insert (10). A method is provided for manufacturing the silencer insert.

Claims

1. A silencer, comprising: a housing; and a silencer insert received by said housing, the silencer insert comprising a first partition wall defining a first plane; a second partition wall defining a second plane, the second plane being different from the first plane; a connecting wall defining a third plane, the third plane being different from the first plane, the third plane being different from the second plane, and the connecting wall being arranged between the first partition wall and the second partition wall, wherein: at least one wall of a wall group consisting of the first partition wall, the second partition wall, and the connecting wall comprises at least one perforated area; the connecting wall is formed in one piece with both, the first partition wall and the second partition wall; and the first plane and the second plane are parallel or the first plane and the second plane are at an angle relative to each other of not more than 60°; the housing comprising a housing coupling portion; at least one wall of the wall group comprising an insert coupling portion at a perimeter thereof, which insert coupling portion is not connected to another wall of the wall group; the insert coupling portion comprising at least one of a protrusion and recess along a coupling portion circumferential direction; and the insert coupling portion being configured for engaging the housing coupling portion.

2. The silencer according to claim 1, wherein the third plane and at least one of the first plane and the second plane are at an angle between 20° and 90° relative to each other.

3. The silencer according to claim 1, wherein: at least one of the first partition wall, the second partition wall, and the connecting wall comprises a rim portion at a perimeter part not connected to another wall; the perimeter part is folded by between 70° and 110° relative to a corresponding plane of the at least one of the first partition wall, the second partition wall, and the connecting wall or the perimeter part is folded to be perpendicular relative to the corresponding plane of the at least one of the first partition wall, the second partition wall, and the connecting wall; and the perimeter part forms a housing abutting face for abutting the housing.

4. The silencer according to claim 1, wherein: the housing coupling portion has a bead shape or forms a protrusion extending into an interior of the housing; and the housing coupling portion engages the coupling portion of the silencer insert.

5. The silencer according to claim 1, wherein at least one of the first partition wall, the second partition wall, and the connecting wall comprises at least one elevated stiffening portion, the elevated stiffening portion defining a plane parallel to the plane defined by the respective wall and spaced from the respective wall by a distance that is at least double a wall thickness of the respective wall.

6. The silencer insert according to claim 1, wherein at least one of the first partition wall, the second partition wall, and the connecting wall comprises at least one through hole for an exhaust gas pipe.

7. The silencer according to claim 6, further comprising at least an exhaust gas pipe passing through the housing, wherein: the exhaust gas pipe passes through the at least one through hole; the exhaust gas pipe comprises, adjacent to the through hole, at least one portion with an exhaust gas pipe diameter that is increased relative to a diameter of the through hole or comprises, adjacent to the through hole, an exhaust gas pipe wall portion that is pressed radially outwards.

8. A method for manufacturing multiple silencer inserts from one single sheet metal strip, each silencer insert comprising a first partition wall defining a first plane, a second partition wall defining a second plane, the second plane being different from the first plane, a connecting wall defining a third plane, the third plane being different from the first plane, the third plane being different from the second plane, and the connecting wall being arranged between the first partition wall and the second partition wall, wherein at least one wall of a wall group consisting of the first partition wall, the second partition wall, and the connecting wall comprises at least one perforated area, the connecting wall is formed in one piece with both, the first partition wall and the second partition wall, and the first plane and the second plane are parallel or the first plane and the second plane are at an angle relative to each other of not more than 60°, the method comprising the steps of: providing a sheet metal strip; perforating the sheet metal strip to form at least one perforated area per silencer insert; cutting portions of the sheet metal strip to size to form the first partition wall and the second partition wall as a pair of partition walls of each silencer insert which pair of partition walls are spaced apart by the connecting wall of each silencer insert; bending the portion of the sheet metal strip forming the pair of partition walls with respect to the portion of the sheet metal strip forming the connecting wall by between 20° and 160°; providing at least one through hole per silencer insert, for an exhaust gas pipe, in at least one wall of the wall group of each silencer insert; and cutting the connecting wall to size to separate the multiple silencer inserts from one another.

9. The method according to claim 8, further comprising the step of deep-drawing the sheet metal strip to form at least one elevated stiffening portion per silencer insert after the step of providing the sheet metal strip and before the step of cutting the portions of the sheet metal strip forming the partition walls of each silencer insert to size.

10. The method according to claim 9, further comprising the step of folding of rim portions of the portions of the sheet metal strip forming the partition walls of each silencer insert by between 70° and 110° after the step of cutting the portions of the sheet metal strip forming the partition walls of each silencer insert and before the step of bending the portion of the sheet metal strip forming the pair of partition walls with respect to the portion of the sheet metal strip forming the connecting wall by between 20° and 160°.

11. The method according to claim 9, further comprising the step of providing at least one through hole for an exhaust gas pipe in the connecting wall of each silencer insert after the step of providing at least one through hole for an exhaust gas pipe in at least one partition wall of each silencer insert and before the step of cutting the connecting wall to size.

12. The method according to claim 8, further comprising the step of folding of rim portions of the portions of the sheet metal strip forming the partition walls of each silencer insert by between 70° and 110° after the step of cutting the portions of the sheet metal strip forming the partition walls of each silencer insert and before the step of bending the portion of the sheet metal strip forming the pair of partition walls with respect to the portion of the sheet metal strip forming the connecting wall by between 20° and 160°.

13. The method according to claim 8, further comprising, after the step of cutting the connecting wall to size, folding rim portions, of the portion of the sheet metal strip forming the connecting wall of each silencer insert, by between 70° and 110°.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1A is a perspective view of a silencer in (half) shell construction with the upper shell of the silencer not being illustrated;

(3) FIG. 1B is a perspective view of a silencer insert of the silencer of FIG. 1A;

(4) FIG. 2 is a perspective view of a silencer according to an embodiment with the upper shell of the silencer not being illustrated;

(5) FIG. 3A is a perspective view of a silencer insert of the silencer of FIG. 2;

(6) FIG. 3B is a perspective view of the silencer insert of FIG. 3A with an exhaust gas pipe passed through;

(7) FIG. 4 is a side view of the silencer of FIG. 2;

(8) FIG. 4A is a sectional view through sectional line C-C of the silencer of FIG. 4;

(9) FIG. 4B is a sectional view through sectional line D-D of the silencer of FIG. 4;

(10) FIG. 4C is a detail view showing a detail E from FIG. 4A;

(11) FIG. 5A is a top view of a sheet metal strip, from which several silencer inserts are made simultaneously, illustrating one of different machining states of the sheet metal strip;

(12) FIG. 5B is a top view of a sheet metal strip, from which several silencer inserts are made simultaneously, illustrating another of different machining states of the sheet metal strip;

(13) FIG. 5C is a top view of a sheet metal strip, from which several silencer inserts are made simultaneously, illustrating another of different machining states of the sheet metal strip;

(14) FIG. 5D is a top view of a sheet metal strip, from which several silencer inserts are made simultaneously, illustrating another of different machining states of the sheet metal strip;

(15) FIG. 5E is a top view of a sheet metal strip, from which several silencer inserts are made simultaneously, illustrating another of different machining states of the sheet metal strip;

(16) FIG. 5F is a front view of the sheet metals strip, from which several silencer inserts are made simultaneously, illustrating one of different machining states of the sheet metal strip;

(17) FIG. 5G is a front view of the sheet metals strip, from which several silencer inserts are made simultaneously, illustrating another of different machining states of the sheet metal strip;

(18) FIG. 5H is a left side view of the sheet metal strip from which several silencer inserts are made simultaneously, illustrating one of different machining states of the sheet metal strip;

(19) FIG. 5I is a rear view of the sheet metal strip from which several silencer inserts are made simultaneously, illustrating another, different machining state of the sheet metal strip; and

(20) FIG. 5J is a rear view of the sheet metal strip from which several silencer inserts are made simultaneously, illustrating another, different machining state of the sheet metal strip.

DESCRIPTION OF PREFERRED EMBODIMENTS

(21) Referring to the drawings, in the exemplary embodiments described below, components that are alike in function and structure are designated as far as possible by alike reference numerals. Therefore, to understand the features of the individual components of a specific embodiment, the description of other embodiments and of the summary of the disclosure should be referred to.

(22) In the following, a description of an embodiment of a silencer according to an embodiment is given with reference to FIGS. 2, 3, and 4.

(23) FIG. 2 hereby illustrates a lower shell 1 of the silencer made from a stainless steel sheet by deep drawing and receiving a separate partition wall 5 and a silencer insert 10, both also made from a stainless steel sheet by deep drawing. The separate partition wall 5 and the silencer insert 10 are thereby disposed in depressions embossed into the lower shell 1 of the silencer housing. For the sake of clarity, the upper shell of the silencer housing is not shown, its shape is, however, basically mirror-symmetrical to the shape of the lower shell 1.

(24) In the mounted state shown in FIG. 2, an exhaust gas pipe 2 penetrates a connection wall 13 of the silencer insert 10, which is arranged between a first partition wall 11 and a second partition wall 12, the exhaust gas pipe further penetrating the lower shell 1 of the silencer housing and leading into a space defined between the first partition wall 11, the second partition wall 12, and the connecting wall 13. The first and second partition walls 11 and 12 and the connecting wall 13 arranged between the two partition walls 11 and 12 are made in one piece from a stainless steel sheet. Further, two exhaust gas outlet pipes 3 and 4 penetrating the first and second partition walls 11 and 12 as well as the separate partition wall 5 are led out at opposite ends of the silencer housing between its lower shell 1 and the upper shell.

(25) The structure of the silencer insert 10 can be seen particularly well in FIGS. 3A and 3B. FIG. 3A thereby shows the silencer insert 10 by itself and FIG. 3B shows the silencer insert 10 with the exhaust inlet pipe 2 held by the silencer insert 10.

(26) Referencing FIG. 3B, the first partition wall 11 defines a first plane E1, the second partition wall 12 defines a second plane E2, and the connecting wall 13 defines a third plane E3. The first and second planes E1 and E2 are thereby perpendicular to the third plane E3 forming an angle of 90° with said third plane E3. Further, in the embodiment shown, the two planes E1 and E2 are parallel to one another.

(27) As can be seen particularly well in FIG. 3A, each of the first and second partition walls 11 and 12 as well as the connecting wall 13 comprise several (each of the partition walls four and the connecting wall two) perforated areas 15. Each of the partition walls 11 and 12 has a total of approximately 500 holes formed therein. The connecting wall 13 has 8 holes formed therein that, however, have a significantly bigger diameter than the holes in the partition walls 11 and 12.

(28) Further, the first and second partition walls 11 and 12 each have an elevated stiffening portion 16. The connecting wall 13 is provided with two elevated stiffening portions 16. The elevated stiffening portions thereby define two respective planes which, in the illustrated embodiment, are spaced five times the wall thickness of the respective wall 11, 12, 13 from the plane E1, E2 or E3 defined by the respective wall 11, 12, 13.

(29) In the connecting wall 13 a through hole 17 is provided for the exhaust gas inlet pipe 2 configured to have a funnel-like cross section and being flared up. In each of the first and second partition walls 11 and 12 two through holes are provided for the exhaust gas outlet pipes 3 and 4 that are also shaped to have a funnel-like cross section and being flared up.

(30) At the part of their perimeter not connected to another wall, the first and second partition walls 11 and 12 as well as the connecting wall 13 each have a rim portion 18 folded perpendicularly with respect to the plane E1, E2, or E3 defined by the respective wall thereby being available as abutting face for the lower shell or the upper shell of the silencer as shown in FIG. 2.

(31) Further, the first and second partition walls 11 and 12 comprise near their joint to the connecting wall 13, on each of two opposite sides, two coupling portions 14 adapted to engage with corresponding coupling portions formed at the lower shell 1 and the upper shell of the silencer. This will be explained below in more detail referencing FIGS. 4, 4A, 4B, and 4C.

(32) FIG. 4A thereby shows a cross section through the silencer of FIG. 4 along sectional line C-C, and FIG. 4C shows detail E of FIG. 4A.

(33) Referencing FIG. 4A, the lower shell 1 and the upper shell of the silencer each comprise coupling portions 6 and 7 formed as protrusions protruding into the direction of the interior of the silencer housing. Said protrusions cooperate with coupling portions 14 formed as recessions at the first and second partition walls 11 and 12 thereby preventing movement of the silencer insert 10 in the direction of the exhaust gas inlet pipe 2.

(34) From FIG. 4B showing a cross section through the silencer of FIG. 4 along sectional line D-D, it can be seen how the exhaust gas inlet pipe 2 can be supported in the through hole 17 of the connecting wall 13. In the embodiment shown, the exhaust gas inlet pipe 2 has been re-shaped after passing it through the through hole 17 from its interior such that it comprises a portion 21 on each side of the through hole 17 where the outer diameter of the exhaust gas inlet pipe 2 is increased. In this manner, an axial movement of the exhaust gas inlet pipe 2 relative to the connecting wall 13 can be prevented.

(35) In the following, a method for manufacturing a silencer insert according to the above embodiment will be described referencing FIGS. 5A to 5J. The silencer insert described is thereby quite similar to the silencer insert described above, it is, however, not completely identical to the silencer insert described above.

(36) As shown schematically in FIG. 5A, areas of a sheet metal strip provided in the form of a stainless steel sheet 8 are perforated in a first step. In the embodiment shown, six silencer inserts are made from the stainless steel sheet 8 simultaneously. In FIG. 5A, these six silencer inserts are arranged above each other from bottom to top of the Figure.

(37) Then, the areas of the stainless steel sheet 8 forming the first and second partition walls of the silencer insert are cut free. The respective cutting edges 81 are shown in FIG. 5B. As can be seen from FIG. 5B, the silencer inserts to be formed are, however, still connected along a central strip.

(38) Then, the elevated stiffening portions 16 shown schematically in FIG. 5C are embossed by deep-drawing the stainless steel sheet 8.

(39) After this, the stainless steel sheet 8 is cut to size in the step shown in FIG. 5D for forming the pairs of first and second partition walls 11 and 12 that are each joined by a connecting wall 13.

(40) Dashed lines are thereby illustrated in FIG. 5D, along which rim portions of the first and second partition walls are folded perpendicularly in the subsequent step shown in FIG. 5E. The rim portions of the connecting walls 13 are, however, not yet folded, since the connecting walls 13 of the six silencer inserts are still connected to allow for a joint handling of the silencer inserts. Accordingly, edges along which a rim portion of the connecting walls 13 will be folded at a later stage are still shown dashed in FIG. 5E.

(41) Before that however, the first and second partition walls 11 and 12 are folded relative to the connecting wall 13 in several steps such that each of them is perpendicular to the connecting wall 13. This is shown in FIGS. 5F and 5G representing front views of the stainless steel sheet 8 (front view means a view from the bottom towards the top of the page showing FIG. 5A; the stainless steel sheet 8 is however in a machining state different from the machining state in FIG. 5A). This front view shows the elevated stiffening portions 16 in the connecting wall 13 while the folded rim portions 18 obscure the elevated stiffening portions in the first and second partition walls 11 and 12.

(42) Then, the through holes for the exhaust gas pipes are provided in the first and second partition walls 11 and 12 as well as in the connection wall 13. This is schematically shown in FIG. 5H showing a left side view (left side view means a view from the left towards the right of the page showing FIG. 5A; the stainless steel sheet 8 is however in a machining state different from the machining state in FIG. 5A). The through holes are thereby provided such that the rim portion is flared up, thus facilitating insertion of the exhaust gas pipes and also increasing the contact areas with the exhaust gas pipes.

(43) Then also the connecting walls 13 are cut to size and the silencer inserts are separated. FIGS. 5I and 5J therefore show only one single silencer insert. In a last step also rim portions of the connecting wall 13 are folded perpendicular with respect to the connecting wall 13, as is obvious from a synopsis of FIGS. 5I and 5J, to thereby stiffen the connecting wall 13.

(44) Although a silencer insert with two partition walls and one connecting wall has been described above, the present invention is not limited thereto. The silencer insert may for instance also comprise more than two partition walls with connecting walls arranged therebetween in pairs.

(45) Although a silencer insert has been described above in the context of a silencer in (half) shell construction, the silencer insert may alternatively also be used in a silencer of wound construction.

(46) While the disclosure has been described with respect to certain exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the exemplary embodiments of the disclosure set forth herein are intended to be illustrative and not limiting in any way. Various changes may be made without departing from the spirit and scope of the present disclosure as defined in the following claims. While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

APPENDIX

List of Reference Designations

(47) 1 lower shell of a silencer housing 2 exhaust gas inlet pipe 21 portions of the exhaust gas inlet pipe with increased outer diameter 3 exhaust gas outlet pipe 4 exhaust gas outlet pipe 5 separate partition wall 6 coupling portion in the lower shell of the silencer housing 7 coupling portion in the upper shell of the silencer housing 8 sheet metal strip 10 silencer insert 11 first partition wall 12 second partition wall 13 connecting wall 14 coupling portion of the silencer insert 15 perforated area 16 elevated stiffening portion 17 through hole for an exhaust gas pipe 18 folded rim portion 81 cutting edge E1 first plane E2 second plane E3 third plane