Heat shielding structure of muffler mount

Abstract

To provide a heat shielding structure of a muffler mount capable of suppressing an increase in temperature of the muffler mount.SOLUTION: In a heat shielding structure of a muffler mount according to the present invention, a second heat shielding plate 5 is arranged so as to be spaced from the muffler mount 3 with a clearance C1 between the second heat shielding plate 5 and the muffler mount 3. This can suppress heat conduction of the second heat shielding plate 5 with respect to the muffler mount 3. This blocks head conduction to the muffler mount 3 from the second heat shielding plate 5 in which a temperature becomes high due to radiation heat of a muffler 2, and an increase in temperature of the muffler mount 3 can be effectively suppressed.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heat insulating structure for a muffler mount. [Background technology]

[0002] A known example of a conventional heat shielding structure for a muffler mount is that described in Patent Document 1 below.

[0003] To put it simply, this muffler mount's heat-shielding structure includes a heat shield that covers the outer surface of the rubber muffler mount that suspends the muffler from the underside of the vehicle floor. By covering the outer surface of the muffler mount, the heat shield prevents the temperature of the outer surface of the muffler mount from rising due to radiant heat from the muffler, etc. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 06-040311 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the heat-shielding structure of the conventional muffler mount, the heat shield plate is placed in contact with the outer surface of the muffler mount. As a result, the heat of the heat shield plate, which becomes hot due to convection heat from the muffler, is conducted to the muffler mount, causing the temperature of the muffler mount to rise. This heat conduction has left room for improvement.

[0006] Therefore, the present invention was devised in consideration of the technical issues with the heat-shielding structure of the conventional muffler mount, and aims to provide a heat-shielding structure for a muffler mount that can suppress temperature increases in the muffler mount. [Means for solving the problem]

[0007] In one aspect, the present invention comprises a muffler mount that is suspended from the underside of the floor of a vehicle body and elastically supports a muffler, a first heat shield plate that is provided on the vehicle body and covers a portion of the muffler, and a second heat shield plate that is provided between the muffler mount and the muffler and covers the muffler mount, with a gap between the second heat shield plate and the muffler mount. [Effects of the Invention]

[0008] According to the present invention, the provision of a second heat shield that covers the muffler mount makes it possible to suppress the radiant heat from the muffler that acts on the muffler mount, thereby suppressing the temperature rise of the muffler mount due to the radiant heat from the muffler, and maintaining the performance of the muffler mount.

[0009] Furthermore, according to the present invention, by providing a gap between the second heat shield and the muffler mount, it is possible to suppress heat conduction from the second heat shield to the muffler mount, thereby effectively suppressing temperature rise in the muffler mount. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is an enlarged view of the vicinity of a muffler mount as viewed from the underside of a floor of a vehicle body to which a heat-shielding structure for a muffler mount according to the present invention is applied. [Figure 2] 2 is a view taken along the arrow A in FIG. 1. [Figure 3] 2 is a view taken along the arrow B in FIG. 1. [Figure 4] FIG. 4 is a cross-sectional view taken along line CC in FIG. [Figure 5] 2 is a view taken along the arrow D in FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0011] An embodiment of the heat-shielding structure for a muffler mount according to the present invention will be described in detail below with reference to the drawings. In this embodiment, as in the prior art, the heat-shielding structure for a muffler mount according to the present invention is applied to a muffler mount structure for an automobile. In each drawing, Fr ​​indicates the front of the vehicle, and Rr indicates the rear of the vehicle.

[0012] Fig. 1 shows an enlarged view of a main portion of the muffler mount 3 according to this embodiment, showing an enlarged view of the vicinity of the muffler mount 3, as viewed from the floor underside 11 of the vehicle body 1. Fig. 2 shows a view seen from the direction A in Fig. 1. Fig. 3 shows a view seen from the direction B in Fig. 1. Fig. 4 shows a cross-sectional view taken along line CC in Fig. 3. Fig. 5 shows a view seen from the direction D in Fig. 1.

[0013] 1 to 5, a muffler 2 extends along the front-to-rear direction of the vehicle body 1 on the floor underside 11 of the vehicle body 1. The muffler 2 is connected via a well-known catalyst to the downstream end of an exhaust manifold (not shown) connected to an engine (not shown). The muffler 2 has a first pipe 21 located upstream, a second pipe 22 located downstream, and an elliptical cylindrical silencer 23 located between the first pipe 21 and the second pipe 22. The muffler 2 is elastically suspended and supported from the floor underside 11 of the vehicle body 1 via a ring-shaped muffler mount 3 made of an elastic material (e.g., rubber material) that connects a vehicle-side mount rod 10 fixed to the floor underside 11 of the vehicle body 1 by welding to a muffler-side mount rod 20 fixed to the silencer 23 by welding.

[0014] Here, the vehicle-body mount rod 10 is formed in the shape of a hollow, small-diameter cylinder and has a rod portion 101. The rod portion 101 is connected to the floor underside 11 of the vehicle body 1 via a rod fixing portion 102 (see FIG. 2 ). The rod portion 101 is integrally formed with a first mount insertion portion 101a and a floor connection portion 101b. The first mount insertion portion 101a is provided at one longitudinal end of the vehicle-body mount rod 10 and is inserted into a first rod insertion hole 31 (described below) of the muffler mount 3. The floor connection portion 101b is provided at the other longitudinal end of the vehicle-body mount rod 10 and is fixed to the floor underside 11 of the vehicle body 1 via the rod fixing portion 102 by welding, and is supported by the floor underside 11 via the rod fixing portion 102.

[0015] Furthermore, the vehicle-side mount rod 10 is provided with a first large-diameter section 101c and a second large-diameter section 101d at both longitudinal ends of the first mount insertion section 101a. These sections are stepped and have larger diameters than the first mount insertion section 101a. The first large-diameter section 101c and the second large-diameter section 101d have outer diameters larger than the inner diameter of the first rod insertion hole 31 (described later). The first large-diameter section 101c and the second large-diameter section 101d are located adjacent to both end faces 301, 302 of the muffler mount 3, respectively, thereby restricting relative movement of the vehicle-side mount rod 10 with respect to the muffler mount 3 in the extension direction.

[0016] On the other hand, the muffler-side mount rod 20 has a rod portion 201 formed in the shape of a hollow small-diameter cylinder, and a rod fixing portion 202 welded along the outer periphery of the rear end face 232 of the silencer 23 to fix the rod portion 201 to the rear end face 232 of the silencer 23. The rod portion 201 is provided at one longitudinal end and integrally includes a second mount insertion portion 201a that is inserted into a second rod insertion hole 32 (described later) of the muffler mount 3, and a muffler connection portion 201b that is provided at the other longitudinal end and is connected to the outer periphery of the silencer 23 via the rod fixing portion 202 by welding.

[0017] The muffler-side mount rod 20 is provided with a first large-diameter section 201c and a second large-diameter section 201d at both longitudinal ends of the second mount insertion section 201a. The first large-diameter section 201c and the second large-diameter section 201d have outer diameters larger than the inner diameter of the second rod insertion hole 32 (described later). The first large-diameter section 201c and the second large-diameter section 201d are located adjacent to both end faces 301, 302 of the muffler mount 3, respectively, thereby restricting relative movement of the muffler-side mount rod 20 with respect to the muffler mount 3 in the extension direction.

[0018] 1 to 3, the muffler mount 3 is made of an elastic material such as rubber and is formed to have a generally elliptical shape in plan view, with a thickness corresponding to the longitudinal width of the first mount insertion portion 101a and the second mount insertion portion 201a. The muffler mount 3 has a first rod insertion hole 31 at one longitudinal end, through which the first mount insertion portion 101a of the vehicle-side mount rod 10 is inserted. The muffler mount 3 has a second rod insertion hole 32 at the other longitudinal end, through which the second mount insertion portion 201a of the muffler-side mount rod 20 is inserted. The muffler mount 3 also has a generally H-shaped cutout portion 33 between the first rod insertion hole 31 and the second rod insertion hole 32.

[0019] A first heat shield 4 is provided on the floor underside 11 of the vehicle body 1 to protect the floor underside 11 from radiant heat from the muffler 2. The first heat shield 4 has a generally U-shaped cross section perpendicular to its longitudinal direction, i.e., the front-to-rear direction of the vehicle body 1, and integrally includes a bottom 40 and a first side wall 41 and a second side wall 42 rising from both side edges of the bottom 40. With this configuration, the bottom 40 of the first heat shield 4 is fixed to the floor underside 11 of the vehicle body 1, and the bottom 40, the first side wall 41, and the second side wall 42 cover the upper part of the silencer 23, thereby protecting the floor underside 11 from radiant heat from the muffler 2. The first side wall 41 has a notch 43 at a position facing the muffler mount 3 to avoid interference with the muffler-side mount rod 20.

[0020] Additionally, silencer 23 is provided with a second heat shield 5 that is disposed in cutout portion 43 of first heat shield 4 and is interposed between silencer 23 and muffler mount 3 to protect muffler mount 3 from radiant heat from muffler 2. As shown in Figures 1 to 5, for example, second heat shield 5 is formed by bending a metal plate into a generally L shape (see Figure 1), and integrally includes an end wall portion 51 that faces rear end surface 232 of silencer 23, and a side wall portion 52 that extends from the side end of end wall portion 51 toward the front side of vehicle body 1 and faces cutout portion 43 of first heat shield 4 to cover muffler mount 3.

[0021] The end wall 51 extends in the width direction of the vehicle body 1, which is perpendicular to the front-to-rear direction of the vehicle body 1, and is positioned opposite the rod fixing portion 202 of the muffler-side mount rod 20, one widthwise end of which is welded to the rear end surface 232 of the silencer 23, and is fixed by welding to the rod fixing portion 202 of the muffler-side mount rod 20. In other words, the end wall 51 is fixed to the rear end surface 232 of the silencer 23 via the rod fixing portion 202 of the muffler-side mount rod 20.

[0022] The end wall portion 51 has a generally rectangular window portion 510 penetrating along the longitudinal direction of the vehicle body 1 at the other end in the width direction that does not face the silencer 23 in the longitudinal direction of the vehicle body 1, in a region that does not face the muffler-side mount rod 20 in the longitudinal direction of the vehicle body 1. That is, the provision of the window portion 510 allows convective heat from the muffler 2 flowing from the front side of the vehicle body 1 to be guided to the rear of the vehicle body 1 through the window portion 510, as indicated by arrow H in FIG. 1 . The window portion 510 is not limited to the rectangular shape exemplified in this embodiment and can be formed into any shape. It is also desirable that the window portion 510 be relatively large and formed in a position that does not face other components in the longitudinal direction of the vehicle body 1. This allows convective heat from the muffler 2 to be efficiently guided to the rear of the vehicle body 1.

[0023] The side wall portion 52 extends from the rear end side of the silencer 23 toward the front of the vehicle body 1 so as to face the cutout portion 43 of the first heat shield plate 4, and is provided between the silencer 23 and the muffler mount 3 so as to face the inner end surface 301 of the muffler mount 3. In this case, the side wall portion 52 is arranged so as to be separated from the muffler mount 3 by a gap C1. The side wall portion 52 is also arranged closer to the muffler mount 3 than the first heat shield plate 4 in the width direction of the vehicle body 1. In other words, as shown in FIG. 2 , the side wall portion 52 is arranged so as to be closer to the muffler mount 3 than the first heat shield plate 4 when viewed from the front side of the vehicle body 1.

[0024] Additionally, a mount rod insertion hole 520, which is cut out to a size larger than the cross-sectional shape of the muffler-side mount rod 20, is provided in the side wall 52 and extends through the side wall 52 in the width direction of the vehicle body 1. In other words, the muffler-side mount rod 20 is inserted into the mount rod insertion hole 520 in a non-contact state, forming a gap C2 between the second heat shield 5 (side wall 52) and the muffler-side mount rod 20.

[0025] Before hanging the muffler 2 (silencer 23) from the muffler mount 3, the second heat shield 5 configured as described above is fixed by welding the end wall portion 51 to the rear end surface 232 of the silencer 23 via the muffler-side mount rod 20 with the muffler-side mount rod 20 inserted into the mount rod insertion hole 520. Then, the muffler-side mount rod 20 exposed to the outside of the second heat shield 5 through the mount rod insertion hole 520 is inserted into the second rod insertion hole 32 of the muffler mount 3. As a result, the muffler 2 is elastically suspended and supported by the muffler mount 3, which is suspended from the vehicle-side mount rod 10 fixed to the floor underside 11 of the vehicle body 1.

[0026] (Effects of this embodiment) In the heat shielding structure of the conventional muffler mount 3, the heat shield plate is provided in contact with the outer surface of the muffler mount 3. As a result, the heat of the heat shield plate, which becomes hot due to the convection heat of the muffler 2, is conducted to the muffler mount 3, causing the temperature of the muffler mount 3 to rise due to this heat conduction, and there is still room for improvement.

[0027] In contrast, the heat shielding structure for the muffler mount according to this embodiment is provided with a second heat shielding plate 5 that covers the muffler mount 3, making it possible to suppress radiant heat from the muffler 2 acting on the muffler mount 3. This suppresses a rise in temperature of the muffler mount 3 due to radiant heat from the muffler 2, and allows the muffler mount 3 to maintain good performance.

[0028] Furthermore, in this embodiment, the second heat shield 5 is positioned so as to be separated from the muffler mount 3 with a gap C1 between them. This makes it possible to suppress heat conduction from the second heat shield 5 to the muffler mount 3. This blocks heat conduction from the second heat shield 5, which becomes hot due to the radiant heat of the muffler 2, to the muffler mount 3, effectively suppressing the temperature rise of the muffler mount 3.

[0029] Furthermore, in this embodiment, the second heat shield 5 is disposed closer to the muffler mount 3 than the first heat shield 4 in the longitudinal direction of the vehicle body 1. Therefore, as shown by arrow H in Figure 1, the side wall portion 52 of the second heat shield 5 can effectively prevent convection heat flowing between the muffler 2 (silencer 23) and the first heat shield 4 from being transferred to the muffler mount 3. This makes it possible to more effectively prevent the temperature rise of the muffler mount 3.

[0030] In this embodiment, the second heat shield 5 is positioned away from the muffler-side mount rod 20 via a mount rod insertion hole 520 that can form a gap C2 between the second heat shield 5 (side wall portion 52) and the muffler-side mount rod 20. Therefore, the gap C2 suppresses heat conduction from the muffler-side mount rod 20 to the second heat shield 5, making it possible to suppress a temperature rise in the second heat shield 5. This effectively suppresses a temperature rise in the muffler mount 3.

[0031] Furthermore, in this embodiment, the second heat shield 5, whose side wall portion 52 is disposed opposite the muffler mount 3, is fixed to the muffler-side mount rod 20 (rod fixing portion 202) welded to the muffler 2 (silencer 23) via the end wall portion 51 disposed relatively far from the muffler mount 3. This makes it possible to suppress heat conduction from the muffler 2 (silencer 23) to the side wall portion 52 disposed opposite the muffler mount 3. This effectively suppresses temperature rise in the muffler mount 3.

[0032] Furthermore, the second heat shield 5 is fixed to the muffler-side mount rod 20 (rod fixing portion 202), which allows the second heat shield 5 and the muffler 2 (silencer 23) to be configured as a single unit. This improves the ease of assembling the muffler 2 to the vehicle body 1, and allows for improved productivity of the vehicle body 1.

[0033] In this embodiment, the end wall 51 is provided with a window 510 that penetrates in the front-to-rear direction of the vehicle body 1. This allows convection heat from the muffler 2 that flows between the side wall 52 and the silencer 23 to escape to the rear of the end wall 51 through the window 510. This makes it possible to suppress the transfer of convection heat from the muffler 2 to the muffler mount 3, and more effectively suppresses temperature increases in the muffler mount 3.

[0034] The present invention is not limited to the configurations exemplified in the above-described embodiments, and can be freely modified according to, for example, the specifications of the vehicle body 1 and muffler 2 to which the present invention is applied.

[0035] In particular, the shape of the second heat shield 5, the mounting position and mounting means of the second heat shield 5 are not limited to the forms exemplified in the above embodiment, but can be changed as desired depending on the layout of the floor underside 11 of the vehicle body 1, the specifications of the muffler 2, etc. [Explanation of symbols]

[0036] 1...Body 10...Vehicle body side mounting rod 11...Underside of floor 2...Muffler 20...Muffler side mounting rod 21...First pipe 22...Second pipe 23...Silencer 3...Muffler mount 3 31...First rod insertion hole 32...Second rod insertion hole 4...First heat shield 43...Notch 5...Second heat shield 51...end wall 510...Window section 52...Side wall 520...Mount rod insertion hole C1...gap C2...Gap

Claims

1. a muffler mount that is suspended from the underside of the vehicle floor and elastically supports the muffler; a first heat shield plate provided on the vehicle body and covering a portion of the muffler; a second heat shield plate provided between the muffler mount and the muffler and covering the muffler mount; Equipped with A gap is provided between the second heat shield plate and the muffler mount. Heat-shielding structure of muffler mount.

2. The heat insulating structure of a muffler mount according to claim 1, The muffler is suspended and supported by the muffler mount via a muffler-side mount rod extending from the muffler, The second heat shield plate is disposed closer to the muffler mount than the first heat shield plate. Heat-shielding structure of muffler mount.

3. The heat insulating structure of a muffler mount according to claim 2, the second heat shield plate is disposed at a distance from the muffler-side mount rod; Heat-shielding structure of muffler mount.

4. The heat insulating structure of a muffler mount according to claim 2, the second heat shield plate has an end wall portion that covers a rear end side of the muffler, and a side wall portion that is bent from a side edge of the end wall portion toward the front side of the vehicle body and covers the muffler mount, The end wall portion is fixed to the muffler-side mount rod. Heat-shielding structure of muffler mount.

5. The heat insulating structure of a muffler mount according to claim 4, The end wall portion has a window portion penetrating in the front-rear direction of the vehicle body. Heat-shielding structure of muffler mount.

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