JP2006002763A - Shell for muffler - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shell for mufflers capable of being prevented from deformation due to evaporation of the water having intruded to between an inner shell and an outer shell, for a muffler having a cylindrical shape with a section other than genuine circle, for example ellipse, race track shape, etc., where minor circular arc portions and major circular arc portions are formed alternately, in which the cylindrical shell body constituting a muffler body is formed in two layers, i.e. the inner shell and the outer shell. <P>SOLUTION: The outer shell 12 of the shell body part 1 has a cylindrical shape with a section where minor circular arc portions are provided, and on each minor circular arc portion, four stretches of outward facing beads 2 continuing in the circumferential direction are formed at a certain spacing in the axial direction, and thereby the gaps h1 and h2 between the inner shell 11 and the outer shell 12 in each major circular arc portion on the shell body part 1 are put in communication through an inside groove 2a of the outward facing beads 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a muffler shell constituting a muffler body.

Conventionally, as a muffler shell constituting a muffler main body, as shown in a schematic cross-sectional view of FIG. 7, the shell main body portion is composed of two layers of an inner shell and an outer shell, and the cross section is like an ellipse or a racetrack type. There is known a muffler shell formed in a cylindrical cross section other than a perfect circle in which small arc portions and large arc portions are alternately formed (see, for example, Patent Document 1).
JP 2002-206422 A (page (2) of the specification, FIGS. 1 and 2)

However, as shown in the schematic cross-sectional view of FIG. 7, in the muffler in which the cylindrical shell main body 101 constituting the muffler main body is composed of two layers of the inner shell 102 and the outer shell 103, the cylindrical shell main body portion. In order to close both end openings of 101, the ends of both end plates are connected by winding or welding, but a small gap is formed between shell body 101 and the end plate.
Therefore, the water accumulated in the lower part in the hollow part of the muffler main body enters the gap between the inner shell 102 and the outer shell 103 through this gap due to capillary action.
When the water is heated at the temperature of the exhaust gas and vaporized, the pressure in the gap increases.

Here, when the rate of pressure increase in the gap exceeds the rate at which the steam escapes from the gap and the pressure decreases, the pressure in the gap between the inner shell 102 and the outer shell 103 rises abnormally. There has been a problem that the shell 102 and the outer shell 103 are deformed.
In addition, water applied to the outer surface of the shell main body due to traveling of the vehicle may similarly enter the gap between the inner shell 102 and the outer shell 103.

  Such a problem can be solved by forming a communication path that communicates between the gap between the inner shell 102 and the outer shell 103 and the outside of the outer shell 103 on the upper surface side of the shell body 101. However, in the case of a muffler formed in a cylindrical cross section other than a perfect circle in which a small arc portion and a large arc portion are alternately formed, such as an ellipse or a race track type, the left and right small arc portions thereof In this case, the inner shell 102 and the outer shell 103 are in close contact with each other so that the gap is closed, and therefore, there is no escape space for the steam generated between the inner shell 102 and the outer shell 103 in the lower large arc portion. There is a risk that the pressure in the gap between the shell 102 and the outer shell 103 will increase, causing the inner shell 102 and the outer shell 103 to be deformed. .

  In addition, if a communication path communicating with the outside is formed between the inner shell 102 and the outer shell 103 in the lower large arc portion, mud, water spray, antifreezing agent and the like are likely to enter from the lower side of the vehicle via the communication path. Therefore, it is not preferable.

  The problem to be solved by the present invention is that the cylindrical shell main body constituting the muffler main body is composed of two layers of an inner shell and an outer shell, and the cross section is a small arc portion such as an ellipse or a racetrack type. A muffler shell that can prevent deformation of the shell due to vaporization of water that has entered between the inner shell and the outer shell in a muffler formed in a cylindrical cross section other than a perfect circle in which large arc portions are alternately formed. Is to provide.

  In order to solve the above-mentioned problem, the muffler shell according to claim 1 has a shell main body portion formed of two layers of an inner shell and an outer shell, and a cross section having a small arc portion and a large arc shape such as an ellipse or a racetrack type. In the muffler shell formed in a cylindrical cross section other than the perfect circle formed alternately with the portion, each small arc portion of the cylindrical cross section of the outer shell is convex outward or concave inward along the circumferential direction. An inner shell and an outer shell in each large arc portion of the shell main body through a circumferential gap formed on the inner groove of the first bead or on both sides of the first bead. A space between the inner shell and the outer shell and the outside of the outer shell is communicated with the upper surface side of the shell main body. And a means, characterized in that road is provided.

  In the muffler shell according to claim 2, the shell main body portion is composed of two layers of the inner shell and the outer shell, and the cross section is formed alternately with the small arc portion and the large arc portion such as an ellipse or a racetrack type. In a muffler shell formed in a cylindrical cross section other than a perfect circle, a second bead that protrudes outward or concave inward along the circumferential direction of each small arc portion of the cylindrical cross section of the inner shell. A circumferential gap formed on both sides of the second bead by being formed, or a gap between the inner shell and the outer shell in each large arc portion of the shell body through a groove inside the second bead. A communication passage is provided on the upper surface side of the shell main body portion to communicate between the gap between the inner shell and the outer shell and the outside of the outer shell. And a means, characterized in.

  A muffler shell according to a third aspect is the muffler shell according to the first or second aspect, wherein the portion where the communication path winds and fixes the inner shell and the outer shell in a cylindrical shape is partially welded by spot welding or the like. Thus, the gap is formed in a portion other than the welded portion.

  The muffler shell according to claim 4 is the muffler shell according to any one of claims 1 to 3, wherein the first bead or the second bead is provided at a predetermined interval in the axial direction of the shell main body. A plurality of lines are formed.

  In the muffler shell according to claim 1, as described above, the first bead that is convex outward or concave inward along the circumferential direction is formed in each small arc portion of the cylindrical cross section of the outer shell. A gap between the inner shell and the outer shell in each large arc portion of the shell main body portion is communicated via a groove in the inner side of the first bead or a circumferential gap formed on both sides of the first bead. The upper main body of the shell main body is provided with a communication path that communicates between the gap between the inner shell and the outer shell and the outside of the outer shell. In which the steam generated between the inner shell and the outer shell passes through a circumferential gap formed in a groove inside the first bead or on both sides of the first bead. After easily it flows into the gap between the definitive inner shell and outer shell, and is discharged from the communication passage to the outside of the shell main body.

  Therefore, the cylindrical shell main body constituting the muffler main body is composed of two layers of an inner shell and an outer shell, and the cross section is formed alternately with small arc portions and large arc portions such as an ellipse or a racetrack type. In the muffler formed in the cylindrical cross section other than the perfect circle, it is possible to prevent the shell from being deformed due to vaporization of water that has entered between the inner shell and the outer shell.

  In addition, since the first bead is formed on the outer shell, the rigidity of the outer shell is increased, and thereby, radiated sound can be suppressed.

  In the muffler shell according to claim 2, as described above, the second bead that is convex outward or concave inward along the circumferential direction is formed in each small arc portion of the cylindrical cross section of the inner shell. Accordingly, the gap between the inner shell and the outer shell in each large arc portion of the shell main body portion is communicated with each other through a circumferential gap formed on both sides of the second bead or a groove inside the second bead. The upper main body of the shell main body is provided with a communication path that communicates between the gap between the inner shell and the outer shell and the outside of the outer shell. The large arc portion above the circumferential gap formed on the both sides of the second bead or the inner groove of the second bead where steam generated between the inner shell and the outer shell in the portion is formed After easily it flows into the gap between the definitive inner shell and outer shell, and is discharged from the communication passage to the outside of the shell main body.

  Therefore, the cylindrical shell main body constituting the muffler main body is composed of two layers of an inner shell and an outer shell, and the cross section is formed alternately with small arc portions and large arc portions such as an ellipse or a racetrack type. In the muffler formed in the cylindrical cross section other than the perfect circle, it is possible to prevent the shell from being deformed due to vaporization of water that has entered between the inner shell and the outer shell.

  In addition, since the second bead is formed on the inner shell, the rigidity of the inner shell is increased, and thereby, radiation sound can be suppressed.

  In the muffler shell according to claim 3, as described above, a portion other than the welded portion is formed by performing partial welding by spot welding or the like on the portion where the communication path is wound around the inner shell and the outer shell in a cylindrical shape. Thus, the communication path can be formed without requiring special processing such as making a hole in the outer shell.

  In the muffler shell according to claim 4, as described above, a plurality of the first beads or the second beads are formed at predetermined intervals in the axial direction of the shell main body portion, whereby the axial direction of the shell main body portion is formed. The deformation of the shell can be prevented over the entire length.

  Embodiments of the present invention will be described below with reference to the drawings.

The muffler shell according to the first embodiment corresponds to the invention described in claims 1, 3, and 4.
First, the muffler shell of Example 1 will be described with reference to the drawings.
1 is a plan view showing a muffler shell of Example 1, FIG. 2 is an end view taken along line II-II in FIG. 1, and FIG. 3 is an end view taken along line III-III in FIG.

  As shown in FIGS. 1 to 3, the shell for the muffler of the first embodiment is obtained by winding the flat plate twice and performing partial welding P on the mating portion by spot welding so that the shell main body portion 1 becomes the inner shell 11 and the outer shell. 12 and the cross section is formed into a horizontally long substantially cylindrical shaped cross section of a horizontally long flat cylindrical shape.

  In addition, as described above, the shell main body is formed by a gap formed at a place other than the weld P portion by performing spot welding P at a predetermined interval by spot welding the upper mating portion obtained by winding the flat plate twice. A communication path R (see FIG. 2) that communicates between the gap h <b> 1 between the inner shell 11 and the outer shell 12 and the outside of the outer shell 12 in the upper large arc portion of the portion 1 is formed.

  More specifically, the outer shell 12 of the shell main body 1 has a radially flat shape in a state where the left and right small circular arc portions of the horizontally long flat cylindrical cross section are sandwiched, and the upper and lower large circular arc portions are recessed outward. By forming four outward facing beads (corresponding to the first beads) 2 with a depth of 5 mm and a circumferential length of 75 mm at predetermined intervals in the axial direction. The gaps h1 and h2 between the inner shell 11 and the outer shell 12 in the upper and lower large circular arc portions of the shell main body 1 are communicated with each other through the groove 2a inside the outward bead 2.

  In addition, both ends of the shells 11 and 12 are usually fixed to the plate-like end plates 3 and 3 by welding or lock seam processing, thereby forming a silencing chamber.

Next, operations and effects of the first embodiment will be described.
Since the first embodiment is configured as described above, moisture contained in the exhaust gas comes into contact with each part in the low temperature exhaust pipe or the muffler body when the vehicle is stopped after the vehicle travels or at a low temperature start. The water condenses and accumulates at the bottom of the hollow portion of the muffler body, and this water is placed in the gap h2 between the inner shell 11 and the outer shell 12 in the large arc portion below the shell body portion 1, When entering through the gap between the end portions of both shells 11 and 12, the muffler body is heated by exhaust gas, and the water that has entered the gap h2 is vaporized. From the communication path R constituted by a gap formed at a place other than the weld P portion after easily flowing into the gap h1 between the inner shell 11 and the outer shell 12 in the upper large arc portion through 2a. To be discharged out of the E reel body portion 1, it is possible to suppress the pressure rise in the gaps of water vapor.

  Therefore, in the muffler in which the cylindrical shell main body portion 1 constituting the muffler main body is constituted by two layers of the inner shell 11 and the outer shell 12, and the cross section is formed in a horizontally long flat cylindrical cross section, the inner shell 11 and the outer shell 12 The effect that the deformation | transformation of the shell main-body part 1 by the vaporization of the water which penetrate | invaded during this time can be prevented now is acquired.

  In addition, a communication path R that connects the gap h1 between the inner shell 11 and the outer shell 12 in the upper large arc portion and the outside of the outer shell 12 winds and fixes the inner shell 11 and the outer shell 12 in a cylindrical shape. Since the portion to be welded is partially welded P by spot welding or the like, it is configured by a gap formed at a place other than the welded P portion, and thus special processing such as opening a hole in the outer shell 12 is required. The communication path R can be formed without this.

  Further, by forming a plurality of the outward beads 2 at a predetermined interval in the axial direction of the shell main body 1 (four by four), the shell main body 1 has an axial total length. Deformation can be prevented.

  Further, by forming the outward bead 2 on the outer shell 12, the rigidity of the outer shell 12 is increased, and thereby, it is possible to suppress radiated sound.

Hereinafter, the effect of the first embodiment will be described.
As described above, in the muffler shell of the first embodiment, the outward bead 2 that protrudes outward along the circumferential direction is formed in each small arc portion of the cylindrical cross section of the outer shell 12. A gap between the inner shell 11 and the outer shell 12 in each large circular arc portion of the shell main body 1 is communicated via the groove 2 a inside the outward bead 2. Is provided with a communication path R that communicates the gap between the inner shell 11 and the outer shell 12 and the outside of the outer shell 12, so that the inner shell 12 and the outer shell 12 in the lower large arc portion are provided. The steam generated in the gap h2 passes between the inner shell 11 and the outer shell 12 in the upper large arc portion through the inner groove 2a of the outward bead 2. After flowing into the gap h1 easily, it is discharged from the communication passage R to the outside of the shell main body 1.

  Therefore, deformation of the shell due to vaporization of water that has entered between the inner shell 11 and the outer shell 12 can be prevented.

Next, Example 2 will be described.
The muffler shell according to the second embodiment corresponds to the invention described in claims 2, 3, and 4.
In the description of the second embodiment, the same components as those of the first embodiment are not shown, or the same reference numerals are given and the description thereof is omitted, and only the differences are described.

4 is a plan view showing the muffler shell of Example 2, FIG. 5 is an end view taken along the line VV of FIG. 4, and FIG. 6 is an end view taken along the line VI-VI of FIG.
The second embodiment shows a modification of the muffler shell in the first embodiment. As shown in FIGS. 4 to 6, the left and right small circular arc portions of the cylindrical cross section of the inner shell 11 are arranged around the circumference thereof. By forming the outward bead 20 (corresponding to the second bead) continuous along the direction so as to protrude outward, the circumferential gaps 20b and 20b formed on both sides of the outward bead 20 are reduced. This is different from the first embodiment in that the gaps h1 and h2 between the inner shell 11 and the outer shell 12 in the upper and lower large arc portions of the shell main body 1 are communicated with each other. is there.

  Since the second embodiment is configured as described above, the inner shell 11 and the outer shell 12 in the large arc portion below the shell body 1 through the gaps between the end plates 3 and 3 and the ends of the shells 11 and 12 are used. When the water that has entered the gap h2 between the two is vaporized, the steam passes through the circumferential gaps 20b, 20b formed on both sides of the outward bead 20, and the inner shell in the upper large arc portion. After flowing easily into the gap h <b> 1 between the outer shell 12 and the outer shell 12, it is discharged out of the shell main body 1 from the communication path R formed by a gap formed at a place other than the weld P part.

  Therefore, in the second embodiment, the outward bead 20 that protrudes outward along the circumferential direction is formed in each small circular arc portion of the cylindrical cross section of the inner shell 11, whereby both side portions of the outward bead 20 are formed. A gap between the inner shell 11 and the outer shell 12 in each large arc portion of the shell main body 1 is communicated via circumferential gaps 20b and 20b formed on the upper surface of the shell main body 1. On the side, the inner shell 11 and the outer shell in the lower large arc portion are formed by providing a communication path R that communicates the gap between the inner shell 11 and the outer shell 12 and the outside of the outer shell 12. The steam generated in the gap h <b> 2 with the outer circumferential bead 20 passes through the circumferential gaps 20 b and 20 b formed on both sides of the outward bead 20 in the upper large arc portion. After easily flows into the gap h1 between the N'nasheru 11 and outer shell 12, to be discharged from the communicating path R to the outside of the shell main body 1, it is possible to suppress the pressure rise in the gaps of water vapor.

  Therefore, deformation of the shell due to vaporization of water that has entered between the inner shell 11 and the outer shell 12 can be prevented.

  Although the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and design changes and the like within the scope not departing from the gist of the present invention are included in the present invention.

  For example, in the embodiment, four outward beads 2 are provided, but the number is arbitrary.

  In the embodiment, the shell body portion 1 has a substantially rice ball shape as an example. However, the shell body portion 1 has a horizontally long flat shape such as an ellipse or a racetrack shape, or a substantially rectangular cross section in which each corner portion is a small arc shape. The present invention can be applied to all having a cross-sectional shape other than a perfect circle in which small arc portions and large arc portions are alternately formed, such as a shape.

  Furthermore, in the first embodiment, the outer shell 12 is provided with an outward bead 2 that protrudes outward, and the inner shell 11 and the outer shell 12 in each large circular arc portion of the shell main body 1 are interposed via the inner groove 2a. The gaps are communicated with each other, but the outer shell 12 is provided with a first bead that is recessed inwardly, and each large arc portion of the shell main body 1 via the circumferential gap formed at both ends thereof. In this case, the gap between the inner shell 11 and the outer shell 12 may be communicated.

  Similarly, in the second embodiment, the inner shell 11 is provided with an outward bead 20 that protrudes outward, and each large arc of the shell main body 1 via the circumferential gaps 20b and 20b formed at both ends thereof. Although the gap between the inner shell 11 and the outer shell 12 in the portion is configured to be communicated, a second bead that is recessed inward is provided in the inner shell 11, and the shell main body portion 1 is provided through the groove on the inner side. You may comprise so that the clearance gap between the inner shell 11 and the outer shell 12 in each large circular arc part may be connected.

  Furthermore, all cases where the first bead and the second bead are used in appropriate combination are also within the scope of the present invention.

2 is a plan view showing a muffler shell of Example 1. FIG. It is an end view in the II-II line of FIG. FIG. 3 is an end view taken along line III-III in FIG. 1. 6 is a plan view showing a muffler shell of Example 2. FIG. It is an end elevation in the VV line of FIG. It is an end view in the VI-VI line of FIG. It is a cross-sectional schematic diagram which shows the shell for mufflers of a prior art example.

Explanation of symbols

R communication path 1 shell body 11 inner shell 12 outer shell 2, 20 outward bead 2a groove 20b circumferential clearance 3 end plate h1 clearance h2 clearance

Claims (4)

The shell body is composed of two layers of an inner shell and an outer shell, and the cross section is a cylindrical cross section other than a perfect circle in which small arcs and large arcs are alternately formed like an ellipse or a racetrack type. In the formed muffler shell,
A first bead that is convex outward or inward along the circumferential direction is formed in each small circular arc portion of the cylindrical cross section of the outer shell, so that the groove inside the first bead or the first bead The gap between the inner shell and the outer shell in each large circular arc part of the shell main body part is configured to communicate with each other through a circumferential gap formed on both sides,
A shell for a muffler, characterized in that a communication passage is provided on the upper surface side of the shell main body portion to communicate between a gap between the inner shell and the outer shell and the outside of the outer shell. The shell body is composed of two layers of an inner shell and an outer shell, and the cross section is a cylindrical cross section other than a perfect circle in which small arcs and large arcs are alternately formed like an ellipse or a racetrack type. In the formed muffler shell,
A circumferential direction formed on both sides of the second bead by forming a second bead protruding outward or inward along the circumferential direction in each small arc portion of the cylindrical cross section of the inner shell. The gap between the inner shell and the outer shell in each large arc portion of the shell main body portion is configured to communicate with each other through the gap or the groove inside the second bead.
A shell for a muffler, characterized in that a communication passage is provided on the upper surface side of the shell main body portion to communicate between a gap between the inner shell and the outer shell and the outside of the outer shell.   3. The muffler shell according to claim 1, wherein a part of the communication path that is wound and fixed by winding the inner shell and the outer shell in a cylindrical shape is partially welded by spot welding or the like, to a place other than the welded part. A muffler shell characterized by comprising gaps to be formed.   The muffler shell according to any one of claims 1 to 3, wherein a plurality of the first beads or the second beads are formed at predetermined intervals in the axial direction of the shell main body. Shell for muffler.

Images