Exhaust manifold

Abstract

To provide an exhaust manifold that enables improvement of reliability.SOLUTION: An exhaust manifold includes a set of plate members fixed to an inlet of a merging pipe in which exhaust gas from a plurality of exhaust pipes merges and combined with each other so as to partition the inlet with respect to each of the exhaust pipes. One of the set of plate members includes: a first slit into which the other of the set of plate members is inserted; and one or more of second slits opened in the same direction as that of the first slit.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an exhaust manifold. [Background technology]

[0002] For example, Patent Document 1 describes an exhaust manifold in which a fixing member for fixing multiple exhaust pipes that are grouped together downstream of the exhaust is provided with a set of plates joined to each other in a cross shape via slits. At the end opposite to the open end of the slit, a circular area with a diameter longer than the slit width is formed to alleviate the concentration of stress due to, for example, thermal deformation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-96347 Summary of the Invention [Problem to be solved by the invention]

[0004] However, depending on the size of the circular area, the margin between the slits may become excessively large, reducing the positioning accuracy of each plate and making it impossible to sufficiently mitigate the concentration of stress in the slits.If stress concentrates in the slits, cracks may occur in the plates starting from the slits, reducing the reliability of the exhaust manifold.

[0005] The present invention has been made in view of the above-mentioned problems, and has an object to provide an exhaust manifold that can improve reliability. [Means for solving the problem]

[0006] The exhaust manifold of the present invention is fixed to the inlet of a confluence pipe where exhausts from a plurality of exhaust pipes are converged, and has a set of plate members combined with each other so as to separate the inlet for each of the exhaust pipes, one of the set of plate members having a first slit into which the other of the set of plate members is inserted, and one or more second slits opening in the same direction as the first slits. death , The set of plate members has a substantially rectangular plate surface, and an end portion opposite to the opening end of the second slit is located on a line connecting an end portion opposite to the opening end of the first slit and a corner of the plate surface on one side on which the opening end of the first slit is provided. .

[0007] In the above exhaust manifold, the second slit may extend along the first slit.

[0008] In the above exhaust manifold, the second slit may be provided on each side of the first slit.

[0010] In the above-mentioned exhaust manifold, the other of the set of plate members may have a third slit that engages with one of the set of plate members via the first slit, and a fourth slit that opens in the opposite direction to the third slit. [Effects of the Invention]

[0011] According to the present invention, the reliability of the exhaust manifold can be improved. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a perspective view showing an example of an exhaust manifold. [Figure 2] FIG. 2 is a perspective view showing an example of plate members before and after assembly. [Figure 3] FIG. 3 is a cross-sectional view of the exhaust pipe and the plate member taken along line AA in FIG. [Figure 4] FIG. 4 is a plan view showing an example of one of the plate members. [Figure 5] FIG. 5 is a plan view showing the other plate member. [Figure 6]FIG. 6 is a plan view showing another example of one of the plate members. DETAILED DESCRIPTION OF THE INVENTION

[0013] 1 is a perspective view showing an example of an exhaust manifold 1. The exhaust manifold 1 has exhaust pipes 11 to 14 extending from exhaust ports (not shown) of an internal combustion engine such as an engine, and a collector 10 where the exhaust gases flowing through the exhaust pipes 11 to 14 join together as indicated by the dotted arrows. An exhaust purification device (not shown) that purifies the exhaust gas is connected downstream of the collector 10. Note that this example illustrates a case where the internal combustion engine has four cylinders, but the number of cylinders is not limited.

[0014] The collector 10 is an example of a confluence pipe. The cross-sectional area of ​​the flow path in the collector 10 is larger than the sum of the cross-sectional areas of the exhaust pipes 11 to 14. The downstream ends of the exhaust pipes 11 to 14 are gathered at the inlet 10a of the collector 10 and connected to the collector 10 by welding or the like. An enlarged view of the inlet 10a of the collector 10, designated by the symbol P, is shown at the bottom of FIG. 1. For convenience, the exhaust pipe 12 is shown in the enlarged view by a dotted line.

[0015] A pair of plate members 21 and 22, which are combined so that their plate surfaces are approximately perpendicular to each other, are fixed to the inlet 10a by welding. The plate surfaces of the plate members 21 and 22 are approximately rectangular, and when the inlet 10a is viewed from the front, the plate members 21 and 22 are combined so as to form a cross shape, and are provided to divide the inlet 10a into each of the exhaust pipes 11-14.

[0016] 2 is a perspective view showing an example of plate members 21 and 22 before and after assembly. Plate member 21 has a coupling slit 210, a dummy slit 211, and a dummy slit 212 that open to the outside of collector 10 as viewed from inlet 10a. Plate member 22 has a coupling slit 220 that opens to the inside of collector 10 as viewed from inlet 10a, and dummy slits 221 and 222 that open to the outside of collector 10 as viewed from inlet 10a.

[0017] The plate members 21 and 22 are combined via their respective coupling slits 210 and 220. The widths of the coupling slits 210 and 220 are greater than the thicknesses of the plate members 21 and 22. The coupling slit 210 sandwiches the portion of the plate thickness on an extension of the other coupling slit 220, and the coupling slit 220 sandwiches the portion of the plate thickness on an extension of the other coupling slit 210. The plate members 21 and 22 are fixed to the inlet 10a of the collector 10 with their respective coupling slits 210 and 220 engaged. The open end of the coupling slit 220 of one plate member 22 faces the exhaust port side in FIG. 1, and the open end of the coupling slit 210 of the other plate member 21 faces the exhaust purification device side in FIG. 1. The dummy slits 211, 212, 221, and 222 are used to relieve stress, and details of this will be described later.

[0018] Plate members 21 and 22 are fixed to a seat plate 100 that is provided at the bottom of entrance 10a and has a cross shape when viewed from the front. Seat plate 100 has two metal plates 101 and 102 that are approximately perpendicular to each other. A bottom side portion 21D along the long side of plate surface 21s of plate member 21 is welded to metal plate 102, and a bottom side portion 22D along plate surface 22s of plate member 22 is welded to metal plate 101.

[0019] Fig. 3 is a cross-sectional view of the exhaust pipes 11 to 14 and the plate members 21 and 22 taken along line AA in Fig. 1. Fig. 3 shows a front view of the inlet 10a of the collector 10. The plate members 21 and 22 divide the inlet 10a into four sections, each corresponding to one of the exhaust pipes 11 to 14. Side edge portions 21L, 21R, 22L, and 22R at both ends in the long side direction of the plate members 21 and 22 are welded to the inner peripheral surface 10s of the collector 10.

[0020] Parts of the outer peripheral surfaces 11a to 14a of the exhaust pipes 11 to 14 are in contact with the plate surfaces 21s and 22s of the plate members 21 and 22 and the inner peripheral surface 10s of the collector 10, and are fixed by welding. Further, the downstream end surfaces of the exhaust pipes 11 to 14 are welded to the bottom 10b of the inlet 10a so that the flow paths 110 to 140 of the exhaust pipes 11 to 14 communicate with a flow path (not shown) inside the collector 10 in an airtight state.

[0021] The dummy slits 211, 212, 221, and 222 of the plate members 21 and 22 each open outward from the inlet 10a.

[0022] Fig. 4 is a plan view showing an example of one plate member 21. Fig. 4 shows the plate member 21 when the plate surface 21s is viewed from the front. The coupling slit 210 and the dummy slits 211 and 212 of the plate member 21 open on the same side. The other plate member 22 is inserted into the coupling slit 210. The other plate member 22 is not inserted into the dummy slits 211 and 212. The coupling slit 210 is an example of a first slit, and the dummy slits 211 and 212 are examples of a second slit.

[0023] High-temperature exhaust gas emitted from the internal combustion engine flows through the exhaust pipes 11 to 14, and therefore the plate members 21 and 22 are heated to a high temperature. On the other hand, the collector 10 outside the exhaust pipes 11 to 14 is in contact with the atmosphere and therefore has a lower temperature than the plate members 21 and 22. For this reason, the plate members 21 and 22 may be thermally deformed due to the temperature difference with the collector 10.

[0024] At this time, the side edge portions 21L and 21R of the plate member 21 are welded to the inner peripheral surface 10s of the collector 10. Therefore, as the collector 10 deforms, the plate member 21 is distorted, as shown by the symbols Du and Dd, such that the area on the bottom edge portion 21D side shrinks and the area on the top edge portion 21U side opposite the bottom edge portion 21D expands.

[0025] As a result, stress Fa acts in a direction that widens width h of coupling slit 210 in a region near end 210b on the opposite side of opening end 210a of coupling slit 210. In response to this, a circular region r with a diameter longer than width h is formed in end 210b to alleviate the concentration of stress Fa.

[0026] However, depending on the size of the circular region r, the margin between the connecting slits 210 and 220 may become excessively large, which may reduce the positioning accuracy of each plate member 21 and 22, making it impossible to sufficiently alleviate the concentration of stress Fa on the connecting slit 210.

[0027] Therefore, dummy slits 211 and 212 are formed in the upper side portion 21U of the plate member 21 to relieve the concentration of the stress Fa. The stress Fa acts not only on the joining slit 210 but also on the dummy slits 211 and 212, so the stress Fa is dispersed. Therefore, the concentration of the stress Fa on the joining slit 210 is relieved without increasing the circular area r, improving the reliability of the exhaust manifold 1.

[0028] While the dummy slits 211 and 212 are arranged at equal intervals on both sides of the coupling slit 210 in the long side direction, for example, the present invention is not limited to this and they may be arranged at different positions. Furthermore, the lengths of the dummy slits 211 and 212 are the same, for example, but the present invention is not limited to this and they may be different lengths.

[0029] In addition, in this example, since the dummy slits 211 and 212 are provided on both sides of the coupling slit 210, the stress Fa is dispersed more effectively than when only one of the dummy slits 211 and 212 is provided. Furthermore, the dummy slits 211 and 212 are formed to extend along the coupling slit 210. Therefore, the stress is dispersed more effectively than when the dummy slits 211 and 212 extend in a direction different from that of the coupling slit 210.

[0030] Furthermore, circular regions r1 and r2 are formed at end portions 211b and 212b opposite to opening ends 211a and 212a of dummy slits 211 and 212, similar to end portion 210b of coupling slit 210. Therefore, compared to the case where circular regions r1 and r2 are not formed, stress acting on end portions 211b and 212b of dummy slits 211 and 212 is reduced. Note that circular regions r, r1, and r2 do not necessarily have to be formed.

[0031] Fig. 5 is a plan view showing the other plate member 22. Fig. 5 shows the plate member 22 when the plate surface 22s is viewed from the front. The coupling slit 220 of the plate member 22 opens on the opposite side to the dummy slits 221 and 222. The other plate member 21 is inserted into the coupling slit 220. The coupling slit 220 engages with the mating plate member 21 via the coupling slit 210. The other plate member 21 is not inserted into the dummy slits 221 and 222. The coupling slit 220 is an example of a third slit, and the dummy slits 221 and 222 are examples of a fourth slit.

[0032] The plate member 22 is also affected by the thermal deformation. At this time, the side edges 22L and 22R of the plate member 22 are welded to the inner peripheral surface 10s of the collector 10. Therefore, as the collector 10 deforms, the plate member 22 is distorted, as shown by the symbols Ku and Kd, such that the area on the bottom edge 22D side shrinks and the area on the top edge 22U side opposite the bottom edge 22D expands.

[0033] As a result, stress Fb acts in a direction narrowing the width d of coupling slit 220 in the region near end 220b opposite to opening end 220a of coupling slit 220. Because the mating plate member 21 is inserted into coupling slit 220, deformation due to stress Fb is suppressed by the thickness of plate member 21.

[0034] Furthermore, a circular region R having a diameter greater than the width d is formed at the end 220b of the connecting slit 220 to relieve the concentration of stress Fb at the end 220b. Furthermore, dummy slits 221 and 222 are formed at the upper side 22U of the plate member 22 to relieve the concentration of stress Fb. The stress Fb acts to widen the dummy slits 221 and 222 and is dispersed. This relieves the concentration of stress Fb at the connecting slit 220, improving the reliability of the exhaust manifold 1.

[0035] Furthermore, the dummy slits 221 and 222 are formed so as to extend along the coupling slit 220. Therefore, stress is dispersed more effectively than when the dummy slits 221 and 222 extend in a direction different from that of the coupling slit 220.

[0036] Furthermore, circular regions R1 and R2 are formed at end portions 221b and 222b opposite to opening ends 221a and 222a of dummy slits 221 and 222, similar to end portion 220b of coupling slit 220. Therefore, compared to the case where circular regions R1 and R2 are not formed, stress acting on end portions 221b and 222b of dummy slits 221 and 222 is reduced. Note that circular regions R, R1, and R2 do not necessarily have to be formed.

[0037] While the dummy slits 221 and 222 are arranged at equal intervals on both sides of the coupling slit 220 in the long-side direction as an example, the present invention is not limited to this and they may be arranged at different positions. Furthermore, the coupling slit 220 and the dummy slits 221 and 222 are arranged so that their respective ends 220b, 221b, and 222b are aligned on a straight line La that is approximately parallel to the long sides of the rectangle. This further reduces the concentration of stress Fb on the end 220b of the coupling slit 220.

[0038] Fig. 6 is a plan view showing another example of one plate member 21a. In Fig. 6, the same components as in Fig. 4 are given the same reference numerals, and their description will be omitted. Plate member 21a has dummy slits 211A and 212B that are shorter than dummy slits 211 and 212.

[0039] The dummy slits 211A and 212B open in the same direction as the coupling slit 210. An end 211b opposite to the opening end 211a of the dummy slit 211A is located on a line Lb connecting the end 210b of the coupling slit 210 and one corner CL on the top side 21U. In addition, the end 212b of the dummy slit 212B is located on a line Lc connecting the end 210b of the coupling slit 210 and the other corner CR on the top side 21U.

[0040] A larger stress Fa acts on the portions on the straight lines Lb and Lc than on other portions. Therefore, by positioning the ends 211b and 212b of the dummy slits 211A and 211B on the lines Lb and Lc, respectively, the stress Fa can be suppressed more effectively than in the dummy slits 211 and 212 of FIG.

[0041] The above-described embodiment is a preferred example of the present invention, but the present invention is not limited to this and can be modified in various ways without departing from the spirit of the present invention. [Explanation of symbols]

[0042] 1 exhaust manifold 10 Collector (confluence pipe) 10a entrance 11~14 Exhaust pipe 21, 22 Plate member 210 Connecting slit (first slit) 210a open end 210b end 211, 211A, 212, 212B Dummy slit (second slit) 220 Connecting slit (third slit) 221, 221a, 222, 222a Dummy slit (4th slit)

Claims

1. a pair of plate members fixed to an inlet of a confluence pipe where exhausts from a plurality of exhaust pipes are joined, the plate members being combined with each other so as to separate the inlet for each of the exhaust pipes; one of the pair of plate members has a first slit into which the other of the pair of plate members is inserted, and one or more second slits that open in the same direction as the first slits, The set of plate members has a substantially rectangular plate surface, an end portion of the second slit opposite to the opening end thereof is located on a line connecting an end portion of the first slit opposite to the opening end thereof and a corner portion of the plate surface on one side on which the opening end of the first slit is provided; Exhaust manifold.

2. The second slit extends along the first slit. The exhaust manifold of claim 1 .

3. The second slits are provided on both sides of the first slit.

3. The exhaust manifold according to claim 1 or 2.

4. the other of the pair of plate members has a third slit that engages with one of the pair of plate members via the first slit, and a fourth slit that opens in an opposite direction to the third slit; 3. The exhaust manifold according to claim 1 or 2.

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