JP-2026075816-A - scarf

Abstract

[Challenge] Suppress the effects of thermal expansion. [Solution] The muffler comprises a shell member, an inner pipe, and a plate-shaped stay. The inner pipe extends from an opening in the shell member into the interior of the shell member. The stay comprises a first surface and a second surface facing each other in the thickness direction, and first and second joints provided at each end in the longitudinal direction. The first joint is joined to the outer circumferential surface of the inner pipe. The second joint is joined to the inner circumferential surface of the shell member. The longitudinal direction of the stay is inclined with respect to the extension direction of the inner pipe, and the second joint is located on the opening side of the first joint. The first surface of the stay faces the outer circumferential surface of the inner pipe. [Selection Diagram] Figure 1

Inventors

• 古屋 智大

Assignees

• フタバ産業株式会社

Dates

Publication Date

20260511

Application Date

20241023

Claims (6)

1. A muffler mounted on a vehicle, A shell member having an exhaust passage from the engine inside, An opening edge surrounding the opening that connects the inside and outside of the shell member, An inner pipe is joined to the opening edge and is arranged to extend from the opening into the interior of the shell member, A stay is a long, slender plate-shaped member extending in the longitudinal direction, having a first surface and a second surface facing each other in the thickness direction. The aforementioned stay is, A first joint portion is provided at the first longitudinal end of the stay and is joined to the outer circumferential surface of the inner pipe, A second joint portion is provided at the second end of the stay in the longitudinal direction and is joined to the inner circumferential surface of the shell member, It comprises a main body portion provided between the first joint portion and the second joint portion and extending in the longitudinal direction, The stay is arranged such that its longitudinal direction is inclined with respect to the extension direction of the inner pipe. The second joint is located on the opening side of the first joint, The stay is arranged such that the first surface faces the outer surface of the inner pipe.
2. The muffler according to claim 1, The shell member is a pipe-shaped member extending in the extension direction of the inner pipe, and has a first opening and a second opening at both ends. The inner pipe is joined to the opening edge of the shell member that surrounds the first opening. The second joint is located on the first opening side of the muffler than the first joint.
3. A muffler according to claim 1 or claim 2, The main body is a muffler that spreads out in a roughly flat shape.
4. A muffler according to claim 1 or claim 2, The main body is a muffler having a protruding portion.
5. A muffler according to claim 1 or claim 2, The muffler further comprises an orthogonal portion, which is located between the main body portion and the first joint portion and extends substantially in a planar manner in a direction substantially perpendicular to the extension direction of the section joined to the opening edge portion of the inner pipe.
6. A muffler according to claim 1 or claim 2, The muffler wherein the section of the inner pipe that includes the end located inside the shell member is configured as an inclined section that slopes downward toward the end.

Description

This disclosure pertains to mufflers. As described in Patent Document 1, a muffler comprising a diffuser pipe and a catalytic converter cylinder positioned inside the diffuser pipe is known. This muffler has a plate-shaped stay joined to the outer circumferential surface of the catalytic converter cylinder and the inner circumferential surface of the diffuser pipe, and the catalytic converter cylinder is fixed to the diffuser pipe by this stay. Japanese Patent Application Publication No. 10-205324 Figure 1A is a side view showing the interior of the shell member in the muffler of the first embodiment. Figure 1B is a perspective view of the stay of the first embodiment. Figure 1C is an explanatory diagram of the shell member of the first embodiment where resonance is occurring.This is an explanatory diagram illustrating the process of press-fitting the inner pipe, to which the stay is joined, into the shell member during the manufacturing process of the muffler according to the first embodiment.Figure 3A is an explanatory diagram illustrating the process of press-fitting the inner pipe, to which the stay is joined, into the shell member during the manufacturing process of the muffler of the second embodiment. Figure 3B is a transparent side view showing the inside of the shell member in the muffler of the third embodiment. Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First Embodiment] [(1) Overview] The muffler 1 of the first embodiment is mounted on a vehicle and configured to allow exhaust gas from the vehicle's engine to flow down (see Figure 1A). For example, the muffler 1 may be configured as a small sub-muffler. The muffler 1 has a double-pipe structure that extends along a hypothetical straight axis A, and comprises a shell member 2 corresponding to the outer pipe, an inner pipe 3 corresponding to the inner pipe, and a stay 4. [(2) Shell members] The shell member 2 is, for example, a cylindrical member that extends straight along axis A, and has an exhaust passage inside (see Figure 1A). The cross section of the shell member 2 perpendicular to axis A (hereinafter simply referred to as the cross section) is, for example, circular, and, for example, axis A passes through the center of the cross section of the shell member 2. The shell member 2 comprises first and second openings 20, 21, first and second opening edges 20A, 21A, first and second tapered sections 22, 23, and a central section 24. <First and Second Openings> The first and second openings 20 and 21 are circular openings located at the first and second ends of the shell member 2, respectively. For example, the first opening 20 forms the exhaust inlet of the muffler 1, and the second opening 21 forms the exhaust outlet of the muffler 1. However, the design is not limited to this, and the second opening 21 may form the exhaust inlet of the muffler 1, and the first opening 20 may form the exhaust outlet of the muffler 1. <First and second opening edges> The first and second opening edges 20A and 21A are cylindrical portions that surround the first and second openings 20 and 21, respectively. <First and second tapered sections> The first and second tapered portions 22 and 23 are provided adjacent to the first and second opening edges 20A and 21A, respectively. When viewed from the side, the first and second tapered portions 22 and 23 are inclined with respect to the axis A, and their cross-sections increase towards the center in the direction of axis A in the shell member 2. <Central part> The central portion 24 is a cylindrical part that extends along axis A. The first and second tapered portions 22 and 23 are located at both ends of the central portion 24, respectively. [(3) Inner pipe] The inner pipe 3 is, for example, a cylindrical member that extends straight along axis A (see Figure 1A). Axis A also passes through the center of the cross-section of the inner pipe 3. The first end of the inner pipe 3 is inserted into the first opening edge 20A, and the portion of the outer circumferential surface 32 of the inner pipe 3 near the first end is joined (for example, welded) to the first opening edge 20A. The inner pipe 3 then extends from the first opening edge 20A along axis A into the interior of the shell member 2. In other words, the first opening 30, located at the first end of the inner pipe 3, is positioned to overlap with the first opening 20 of the shell member 2, and the second opening 31, located at the second end, is positioned inside the shell member 2. Therefore, the exhaust gas flowing into the muffler 1 from the first opening 20 first passes through the inner pipe 3, and then flows out into the space between the inner pipe 3 and the shell member 2. Finally, the exhaust gas flows out of the muffler 1 through the second opening 31. [(4) Stay] The stay 4 is provided to support the inner pipe 3 and is an elongated plate-shaped member extending in the longitudinal di