EXHAUST PIPE ELBOW

Abstract

An exhaust pipe formed from two pipe elbows each having a pipe wall and a center axis, each pipe elbow being formed from two half shells, wherein each half shell has an inner edge side (Ri) and an outer edge side (Ra), and the inner edge sides and the outer edge sides can be brought into contact with each other in order to form the pipe elbow, wherein each pipe elbow has an end (S1, S2) and the two ends (S1, S2) can be brought into contact with each other in order to form the exhaust pipe. All four half shells are identical parts, wherein each pipe elbow has only one inlet opening (E1, E2) and only one outlet opening (A1, A2).

Claims

1. An exhaust pipe formed from two pipe elbows, each having a pipe wall and a centre axis, each pipe elbow being formed from two half-shells, wherein each half-shell has an inner edge side Ri and an outer edge side Ra, which can be brought into contact with each other to form the pipe elbow, wherein each pipe elbow has a front side S1, S2, and the two front sides S1, S2 can be brought into contact with each other in order to form the exhaust pipe, wherein all four half-shells are identical parts, wherein the respective pipe elbow has only one inlet opening E1, E2 and only one outlet opening A1, A2.

2. The exhaust pipe according to claim 1, wherein the centre axis of the respective pipe elbow has a curve radius Rm, wherein the curve radius Rm is constant over the length of the centre axis, or varies between the values m1 and m2, with m1<=5 m2.

3. The exhaust pipe according to claim 1, wherein the centre axis of the respective pipe elbow has a curve radius Rm and the pipe elbow has a diameter Dr, wherein the following applies: 2 Rm>Dr or Rm>Dr.

4. The exhaust pipe according to claim 1, wherein the edge side Ri has a length li and the edge side Ra has a length la, wherein on at least one edge side Ri, Ra, a system frame Wi, Wa is provided which is arranged radially offset in relation to the centre axis to the pipe wall, wherein the respective system frame Wi, Wa extends over maximum 50% of the length li, la.

5. The exhaust pipe according to claim 4, wherein on at least one edge side Ri, Ra, a coupling bridge Ki, Ka is provided, which extends over a maximum of 50% of the length li, la, wherein for the purpose of forming the pipe elbow, the coupling bridge Ki, Ka of a half-shell can be brought into a form-fit connection with the edge side Ri, Ra or with a system frame Wi, Wa of the adjacent half-shell.

6. The exhaust pipe according to claim 5, wherein the system frame Wi, Wa and the coupling bridge Ki, Ka are limited to one half Hi, Ha respectively of the edge side Ri, Ra.

7. The exhaust pipe according to claim 1, wherein on at least one front side S1, S2 of the pipe elbow, a shoulder U1, U2 is provided with an expanded diameter D, which forms a sleeve.

8. The exhaust pipe according to claim 5, wherein a cylindrical connection piece is provided, which in the area of the front side S1, S2 can be inserted into the inlet opening E1, E2 or into the outlet opening A1, A2, and against which the shoulder U1, U2 can be brought in contact with in the axial direction.

9. The exhaust pipe according to claim 1, wherein the first pipe elbow has an inlet opening E1 which tensions an inlet plane L1, and the second pipe elbow has an outlet opening A2, which tensions an outlet plane L2, wherein the outlet opening A1 of the first pipe elbow and the inlet opening E2 of the second pipe elbow each have a central point P1, and both pipe elbows can be freely pivoted relative to each other with the planes L1, L2 in relation to a rotation axis R, wherein the axis R cuts the central point P1 and runs tangentially to the centre axis.

10. An exhaust pipe according to claim 1, formed from at least two pipe elbows and at least one connection piece with a length v, wherein the length v determines a distance a between the front side S1 and the front side S2 of the two pipe elbows, wherein connection pieces of different lengths v are provided so that the distance a can be altered.

11. An exhaust pipe according to claim 1, formed a maximum of two, three or four identical pipe elbows, and in each case at most double the number of identical half-shells.

12. The exhaust pipe according to claim 4, wherein the edge side Ri has a length li and the edge side Ra has a length la, wherein on at least one edge side Ri, Ra, a system frame Wi, Wa is provided which is arranged radially offset in relation to the centre axis to the pipe wall, wherein the respective system frame Wi, Wa extends over maximum 20% to 40% of the length li, la.

13. The exhaust pipe according to claim 2, wherein the centre axis of the respective pipe elbow has a curve radius Rm and the pipe elbow has a diameter Dr, wherein the following applies: 2 Rm>Dr or Rm>Dr.

14. The exhaust pipe according to claim 13, wherein the edge side Ri has a length li and the edge side Ra has a length la, wherein on at least one edge side Ri, Ra, a system frame Wi, Wa is provided which is arranged radially offset in relation to the centre axis to the pipe wall, wherein the respective system frame Wi, Wa extends over maximum 20% to 40% of the length li, la.

15. The exhaust pipe according to claim 14, wherein on at least one edge side Ri, Ra, a coupling bridge Ki, Ka is provided, which extends over a maximum of 50% of the length li, la, wherein for the purpose of forming the pipe elbow, the coupling bridge Ki, Ka of a half-shell can be brought into a form-fit connection with the edge side Ri, Ra or with a system frame Wi, Wa of the adjacent half-shell.

16. The exhaust pipe according to claim 15, wherein the system frame Wi, Wa and the coupling bridge Ki, Ka are limited to one half Hi, Ha respectively of the edge side Ri, Ra.

17. The exhaust pipe according to claim 16, wherein on at least one front side S1, S2 of the pipe elbow, a shoulder U1, U2 is provided with an expanded diameter D, which forms a sleeve.

18. The exhaust pipe according to claim 17, wherein a cylindrical connection piece is provided, which in the area of the front side S1, S2 can be inserted into the inlet opening E1, E2 or into the outlet opening A1, A2, and against which the shoulder U1, U2 can be brought in contact with in the axial direction.

19. The exhaust pipe according to claim 18, wherein the first pipe elbow has an inlet opening E1 which tensions an inlet plane L1, and the second pipe elbow has an outlet opening A2, which tensions an outlet plane L2, wherein the outlet opening A1 of the first pipe elbow and the inlet opening E2 of the second pipe elbow each have a central point P1, and both pipe elbows can be freely pivoted relative to each other with the planes L1, L2 in relation to a rotation axis R, wherein the axis R cuts the central point P1 and runs tangentially to the centre axis.

20. An exhaust pipe according to claim 19, formed from at least two pipe elbows and at least one connection piece with a length v, wherein the length v determines a distance a between the front side S1 and the front side S2 of the two pipe elbows, wherein connection pieces of different lengths v are provided so that the distance a can be altered.

Description

BRIEF DESCRIPTION OF THE INVENTION

[0025] Further advantages and details of the invention are explained in the patent claims and in the description and figures, in which:

[0026] FIG. 1 shows a pipe elbow as a connection to a catalyser;

[0027] FIG. 2 shows a cross-section of the connection point of two pipe elbows;

[0028] FIG. 3a shows a pipe elbow with two half-shells in an exploded view;

[0029] FIG. 3b shows a view according to FIG. 3a in an assembled state;

[0030] FIG. 4a shows a view according to FIG. 3a from behind;

[0031] FIG. 4b shows a view according to FIG. 4a in an assembled state;

[0032] FIG. 5a shows a view according to FIG. 4a without a system frame;

[0033] FIG. 5b shows a view according to FIG. 5a in an assembled state;

[0034] FIG. 6 shows a principle sketch for the radius Rm and diameter D;

[0035] FIGS. 7, 8 show a principle sketch for the system frame Wi, Wa and the coupling bridge Ki, Ka.

DETAILED DESCRIPTION OF THE INVENTION

[0036] In the view shown in FIG. 1, an exhaust connecting pipe 6 is connected via a first pipe elbow 1 and via a second pipe elbow 2 to a catalyser 7. Both the first pipe elbow 1 and the second pipe elbow 2 are formed respectively from two half-shells 1a, 1b, 2a, 2b as shown in greater detail in FIGS. 3a to 4b. While the first pipe elbow 1 has a connection plane L1 to the exhaust connecting pipe 6, and the second pipe elbow 2 has a connection plane L2 to the catalyser, both pipe elbows 1, 2 can be turned as required around the rotation axis R. The axis R runs through a central point P1 of a respective inlet or outlet opening E1, E2, A1, A2.

[0037] The first pipe elbow 1 has two connection pieces 1.2, 1.3 for exhaust gas sensors (not shown).

[0038] According to the view shown in FIG. 2, a partial section of an exhaust pipe 3 shown according to FIG. 1, which is composed of both pipe elbows 1, 2 as a cross-section view of the coupling point of both pipe elbows 1, 2. A respective pipe wall 4 has a shoulder U1, U2 in the area of a respective front side S1, S2, which results in an enlarged diameter D (here, D/2) and which forms a sleeve 1.1, 2.1.

[0039] Since both pipe elbows 1, 2 are produced as identical parts as described below, the diameter D is the same for both pipe elbows 1, 2. In order to assemble or plug together both pipe elbows 1, 2, a tubular connection piece 5 is provided which is inserted with its tip end into the respective sleeve 1.1, 2.1. Depending on a length v of the connection piece 5, the distance a between both front sides S1, S2 varies. When both pipe elbows 1, 2 are axially joined, the connection piece 5 can come into contact in the axial direction against the respective shoulder U1, U2.

[0040] The respective pipe elbow 1, 2 has a centre axis 4.1, which in turn has a curve radius Rm sketched in FIG. 6. The rotation axis R shown in FIG. 1 runs tangentially to the centre axis 4.1 and is also shown in FIG. 2.

[0041] As shown in both FIGS. 3a, 4a and in FIGS. 3b, 4b, the respective pipe elbow 1, 2 is formed from two identical half-shells 1a, 1b. The respective half-shells 1a, 1b, 2a, 2b are connected via an edge side Ra, Ri of the length la, li. In order to connect both half-shells 1a, 1b, the respective half-shell 1a, 1b has a system frame Wi, Wa and a coupling bridge Ki, Ka in the area of the edge side Ra, Ri and on the inner side as well as on the outer side. The respective system frame Wi, Wa or respective coupling bridge Ki, Ka here extends over approximately 20% to 40% of the respective length la, li, so that a sufficiently large form-fit connection is provided between both half-shells 1a, 1b, 2a, 2b. The respective system frame Wi, Wa and the respective coupling bridge Ki, Ka are limited to the section of one half Hi, Ha of the edge side Ri, Ra. The respective system frame Wi, Wa or the respective coupling bridge Ki, Ka here does not necessarily extend over the entire half Hi, Ha of the edge side Ri, Ra.

[0042] With the edge side Ra, this is approximately 80%, and with the edge side Ri, approximately 50% of a length la or length li. The system frame Wi, Wa and the coupling bridge Ki, Ka are however preferably arranged symmetrically to each other in relation to a centre Mi, Ma of the edge side Ri, Ra. The system frame Wi, Wa of a half-shell 1a, 1b and the coupling bridge Ki, Ka of the other applied or set down half-shell 1a, 1b are aligned centrally to each other in relation to the direction of the edge side Ri, Ra. The coupling bridge Ki, Ka is here somewhat shorter than the system frame Wi, Wa, or at the most as long as the active length of the system frame Wi, Wa, i.e. its entire length minus the formation diagonals, so that the coupling bridge Ki, Ka can be inserted into the system frame Wi, Wa when the half-shells 1a, 1b are placed against each other.

[0043] The respective half-shells 1a, 1b, 2a, 2b also have a recess 4.2 which holds an exhaust gas sensor.

[0044] According to the exemplary embodiment shown in FIGS. 5a, 5b, only the coupling bridge Ka, Ki and no system frame Wa, Wi is provided. The coupling bridge Ka, Ki is bent inwards and grips the corresponding section of the shell edge Ra of the adjacent shell from behind.

[0045] As can be seen in FIG. 7 with the outer edge Ra as an example, the respective system frame Wi, Wa of the half-shell 1b is formed outwardly by an additional formation of the edge in a radial direction P to the centre axis 4.1, into which the corresponding coupling bridge Ka, Ki of the half-shell 1a, 1b, 2a, 2b to be connected engages in the circumferential direction and forms the form-fit connection in the radial direction P. The coupling bridge Ka, Ki here protrudes opposite the housing edge in the circumferential direction, as shown in FIGS. 3a-5b. A radial misalignment in relation to the housing wall is not necessary.

[0046] According to FIG. 8, no system frame Wa, Wi is provided according to the exemplary embodiment shown in FIGS. 5a, 5b. The coupling bridge Ka, Ki is radially offset inwards in relation to the housing edge, so that the coupling bridge Ka, Ki of the half-shell 1b is in contact internally on the shell edge Ra of the half-shell 1a, and forms the form-fit connection in the radial direction P with the shell edge Ra.

[0047] According to FIG. 6, the curve radius Rm of the centre axis 4.1, i.e. of the respective pipe elbow 1, 2, and a diameter Dr of the respective pipe elbow 1, 2, are shown in a stylized manner. Due to the stipulation that the curve radius Rm must be greater than at least half the diameter Dr or greater than the diameter Dr, the pipe elbow 1, 2 according to the invention differs from other dual-shell exhaust pipes which are bent for other purposes.

LIST OF REFERENCE NUMERALS

[0048] 1 Pipe elbow [0049] 1a Half-shell [0050] 1b Half-shell [0051] 1.1 Sleeve, connecting sleeve [0052] 1.2 Connection piece [0053] 1.3 Connection piece [0054] 2 Pipe elbow [0055] 2a Half-shell [0056] 2b Half-shell [0057] 2.1 Sleeve, connecting sleeve [0058] 3 Exhaust pipe [0059] 4 Pipe wall [0060] 4.1 Central axis [0061] 4.2 Recess [0062] 5 Connection piece [0063] 6 Exhaust connection pipe [0064] 7 Catalyser [0065] A1 Outlet opening [0066] A2 Outlet opening [0067] a Distance between S1, S2 [0068] D Diameter [0069] Dr Diameter [0070] E1 Inlet opening [0071] E2 Inlet opening [0072] Ha Half of Ra [0073] Hi Half of Ri [0074] Ka Coupling bridge [0075] Ki Coupling bridge [0076] L1 Inlet plane [0077] L2 Outlet plane [0078] la Length [0079] li Length [0080] Ma Centre of Ra [0081] Mi Centre of Ri [0082] P Radial direction to 4.1 [0083] P1 Central point [0084] R (Rotation) axis [0085] Ra Outer edge side of 1a, 1b, 2a, 2b [0086] Ri Inner edge side of 1a, 1b, 2a, 2b [0087] Rm Curve radius [0088] m1 Value of Rm [0089] m2 Value of Rm [0090] S1 Front side of 1 [0091] S2 Front side of 2 [0092] U1 Shoulder [0093] U2 Shoulder [0094] v Length of 5 [0095] Wa System frame [0096] Wi System frame