JP2009138601A - Silencer supporting structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent thermal deterioration of mount rubber for a hanger hanging a silencer below a rear part of a vehicle body in a cross arrangement. <P>SOLUTION: The silencer 2 is crossly arranged at a rear part of a suspension cross member 1 at a rear part of a vehicle body, and an upstream exhaust pipe 1 extending across the suspension cross member 1 is connected with a position near a rear side on one end in a vehicle width direction, and a downstream pipe 12 is connected with a position near a front side. Then, in order to restrain thermal deterioration due to radiant heat from the upstream exhaust pipe 11 of a hanger 3 hanging the silencer 2 toward the vehicle body on one end, a heat insulation board 20 is fixed to an upper edge of an end wall 7 of the silencer 2 to cover a vicinity of a connection part of the upstream exhaust pipe 11 from above, and a silencer side bracket 31 for a hanger is fixed on a top face of the heat insulation board 20. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a structure for supporting a silencer, and in particular, a cylindrical silencer is disposed below a rear part of a vehicle body in a horizontal posture with a longitudinal direction substantially in a vehicle width direction, and hanger is attached to the vehicle body at both ends of the silencer. The present invention relates to a silencer support structure for supporting suspension.

A silencer for a vehicle engine is generally formed in a substantially cylindrical shape, and is usually mounted under the rear of the vehicle in a so-called vertical orientation with the longitudinal direction directed in the vehicle front-rear direction. When it becomes large, it becomes difficult to secure a space for mounting the silencer at the rear of the vehicle while avoiding interference with the suspension cross member and the like in the vertical mounting. For this reason, it has been conventionally practiced to increase the size by placing the silencer horizontally and widening it in the vehicle width direction. In that case, the silencer is formed in a substantially cylindrical shape, and is placed below the rear part of the vehicle body in a lateral orientation with the longitudinal direction substantially oriented in the vehicle width direction. It is common to suspend and support the vehicle body with a hanger in this respect (see, for example, Patent Document 1).
JP 2006-207460 A

  Below the rear part of the vehicle body, a fuel tank is usually arranged at the lower position of the rear seat, and a space is provided behind the rear tank, so that a large silencer can be mounted horizontally there. And when the horizontal silencer is configured so that the upstream exhaust pipe on the inlet side and the downstream exhaust pipe on the outlet side are both connected to one end side in the vehicle width direction, a space is created on the other end side in the vehicle width direction. Therefore, the silencer can be increased in the vehicle width direction.

  However, if a silencer is mounted horizontally in the lower part of the rear of the vehicle body and the upstream exhaust pipe is to be connected to the end of the silencer in the vehicle width direction, a hanger for hanging support that is fixed to the end of the silencer And the upstream exhaust pipe become too close, and the hanger mount rubber may be deteriorated due to radiant heat when the unburned gas is burnt after the engine misfires and the temperature of the upstream exhaust pipe rises. .

  Also, when connecting the upstream exhaust pipe to the end of the silencer mounted horizontally in the lower part of the rear of the vehicle body, the upstream exhaust pipe usually has to be bent so as to straddle the rear suspension cross member. After the upstream exhaust pipe straddles the suspension cross member, it looks like the silencer descends at an angle from a high position. For this reason, the upstream exhaust pipe and the hanger are closer together, and the thermal The effect becomes larger, and the problem of thermal deterioration of the mount rubber becomes more prominent.

  In addition, in order to connect both the upstream exhaust pipe and the downstream exhaust pipe to one end side of the silencer, it is necessary to offset the respective connection parts of the upstream exhaust pipe and the downstream exhaust pipe to the opposite sides. If the connection part of the exhaust pipe is offset to the front side of the vehicle, after straddling the suspension cross member, the bending angle of the upstream exhaust pipe that is lowered and connected to the silencer becomes large, and the exhaust resistance increases. Problem arises. Therefore, it is advantageous to offset the connection part of the upstream exhaust pipe to the rear side and offset the connection part of the downstream exhaust pipe to the front side. However, if the upstream exhaust pipe connection part is offset to the rear side in such a way, the upstream exhaust pipe will not be lowered and it will cross the end face of the silencer, the upstream exhaust pipe and the hanger will be closer, and the mount rubber Tends to be more severe thermally.

  Therefore, it is a problem to be able to prevent thermal deterioration of the hanger mount rubber that suspends and supports the silencer in a horizontal position below the rear part of the vehicle body.

  The silencer support structure of the present invention is for solving the above-described problems. A silencer having a substantially cylindrical shape is disposed below the rear part of the vehicle body in a horizontal posture with the longitudinal direction oriented substantially in the vehicle width direction. A silencer support structure that is hung from a hanger and supported by a hanger at the end of the vehicle. The silencer has an exhaust inlet portion and an exhaust outlet portion on the end wall portion on one end side in the vehicle width direction, and the exhaust inlet portion is behind the vehicle longitudinal direction. The exhaust outlet portion is provided in a front-rear direction in the vehicle front-rear direction, and an upstream exhaust pipe extending from the front side in the vehicle front-rear direction is connected to the exhaust inlet portion, and the exhaust outlet portion dives under the upstream exhaust pipe. A downstream exhaust pipe that extends rearward in the vehicle longitudinal direction through the outer side in the vehicle width direction than the upstream exhaust pipe is connected, and an end wall portion on one end side in the vehicle width direction in which the exhaust inlet portion and the exhaust outlet portion of the silencer are provided. Upper edge, upstream Heat shield plate covering the connecting portion near to the exhaust inlet of the trachea from above is fixed, characterized in that the silencer side bracket hanger on the upper surface of the shielding hot plate is fixed.

  This silencer support structure can accommodate the increase in size of the silencer by installing the silencer horizontally below the rear of the vehicle body, and both the upstream exhaust pipe and the downstream exhaust pipe are connected to one end in the vehicle width direction of the silencer. This makes it possible to widen the silencer to the maximum in the vehicle width direction, and the connection part of the upstream exhaust pipe and the downstream exhaust pipe is the rear part of the connection part of the upstream exhaust pipe and the connection part of the downstream exhaust pipe is the front part. In the silencer to be constructed, the hanger supporting the one end to which the upstream exhaust pipe and the downstream exhaust pipe are connected is supported by receiving heat from the upstream exhaust pipe to prevent the mount rubber from being thermally deteriorated. A heat shield that blocks radiant heat is installed between the hanger and the upstream exhaust pipe. A heat shield that covers the vicinity of the connection site to the exhaust inlet of the upstream exhaust pipe from above is fixed to the upper edge of the end wall on the one end side in the vehicle width direction where the outlet is provided, and is attached to the upper surface of the heat shield. It is characterized in that the silencer side bracket for the hanger is fixed.

  In order to prevent thermal deterioration of the hanger, it is effective to install a heat shield so that the hanger blocks the radiant heat from the upstream exhaust pipe. In that case, the hanger that supports the silencer is generally composed of an elastic mounting rubber, a silencer-side bracket and each bracket attached to the vehicle body, and the silencer-side bracket is welded to the end of the silencer. Therefore, it is conceivable to fix a heat shield plate between the upstream exhaust pipe and the mount rubber on the silencer side bracket. However, if the heat shield is fixed to the silencer side bracket welded to the end of the silencer in this way, the heat shield may become a new vibration source. The hanger is an elastic structure that absorbs vibrations unique to the exhaust system, but if the heat shield is fixed to the silencer side bracket, the plate-shaped body will be insulated before the vibration of the exhaust system is absorbed by the hanger. There is a risk that the heat shield plate swings out and is transmitted to the plate, causing vibration that cannot be absorbed. Therefore, according to the present invention, the heat shield plate is directly fixed to the silencer, the hanger silencer side bracket is fixed to the heat shield plate, and the silencer side bracket is supported via the heat shield plate.

  According to this silencer support structure, in a situation where the hanger that suspends and supports the silencer in the horizontal position under the rear of the vehicle body tends to approach the upstream exhaust pipe, the hanger heats up due to the temperature rise of the upstream exhaust pipe due to misfire or the like. Deterioration can be prevented, and the heat shield plate is directly supported by the hanger silencer bracket under direct load, preventing the heat shield plate from becoming a new vibration source. Can do. Since the heat shield plate is supported by the bracket under the load of the entire silencer and does not become free, the heat shield plate can be prevented from becoming a new vibration source. In addition, since the heat shield plate is a plate member and has a surface, it can be firmly fixed to the silencer by welding etc. at the wide surface part, and it can have surface rigidity as a three-dimensional shape, itself Can be suppressed.

  In the silencer support structure, in particular, the silencer main body casing includes a cylindrical body wall part made of a plate material and substantially flat end wall parts at both ends made of a plate material formed separately from the body wall part. The end wall portion is fold-folded so that the peripheral edge portion forms a ring-shaped joint on the barrel wall side, and the edge of the barrel wall portion is fitted into the fold-shaped ring-shaped joint. It is preferable that the heat shield plate is fixed to the lower surface of the upper edge portion which is the back side of the folded edge of the upper edge portion of the end wall on one end side in the vehicle width direction.

  In this case, since the end of the main body casing is a fold joint and the strength of the silencer is high, the heat shield can be firmly fixed and supported.

  In addition, in this silencer support structure, in particular, the heat shield has a curved cross-sectional shape when viewed in the vehicle width direction, and does not overlap the upstream exhaust pipe in plan view in the vicinity of the connection portion to the exhaust inlet of the upstream exhaust pipe. It is preferable that the edge on the front side in the vehicle longitudinal direction is lowered downward.

  With this structure of the heat shield plate, it is possible to improve the cooling performance of the bracket by actively guiding the running wind to the silencer side bracket for the hanger, and the heat shield plate from the silencer itself becoming a high temperature state The heat transmitted to the mounting rubber of the hanger through the bracket can be reduced, the heat load on the hanger can be suppressed, and the heat shield plate has a three-dimensional shape to increase the strength and surface rigidity. .

  In addition, in this silencer support structure, the heat shield has a three-dimensional shape, and the width dimension in the vehicle front-rear direction on the base end side fixed to the silencer is relatively large, and the free end on the outer side in the vehicle width direction It is preferable that the width dimension becomes smaller as it is closer to.

  By configuring the heat shield plate in this way, the strength and surface rigidity of the heat shield plate can be increased, the heat shield plate can be fixed and the hanger support can be strengthened, and the vibration itself can be further reduced. Can be suppressed.

  This silencer support structure is particularly advantageous when the upstream exhaust pipe is disposed across the suspension cross member extending in the vehicle width direction.

  In this case, after the upstream exhaust pipe straddles the suspension cross member, the upstream exhaust pipe is lowered at an angle from a high position with respect to the silencer, and the upstream exhaust pipe and the hanger are closer to each other. The necessity to block radiant heat is remarkable, and the thermal deterioration of the hanger can be effectively suppressed by the heat shield plate.

  As described above, according to the present invention, in a situation where the hanger that supports the silencer in the horizontal position under the rear part of the vehicle body tends to approach the upstream exhaust pipe, the hanger is caused by the temperature rise of the upstream exhaust pipe due to misfire or the like. Can be prevented from thermally degrading, and the heat shield can be prevented from newly becoming a vibration source.

  FIGS. 1-12 has shown an example of embodiment of the silencer support structure of this invention. 1 is a plan view of the silencer, FIG. 2 is a side view of the silencer (viewed from one end in the vehicle width direction), FIG. 3 is a cross-sectional view of the upper portion of the silencer in the vehicle width direction, and FIG. 4 is a rear view of the silencer. FIG. 5 is a bottom view of one end side of the silencer, FIG. 6 is an enlarged detail view of a T portion in FIG. 1, FIG. 7 is a VV cross-sectional view (part) of FIG. 6 is a cross-sectional view taken along the line WW in FIG. 6 (part), FIG. 9 is a cross-sectional view taken along the line XX in FIG. 6 (part), and FIG. FIG. 10 is a perspective view of one end of the silencer (viewed from the left upper front of the vehicle), FIG. 11 is a perspective view of one end of the silencer (viewed from the lower left front of the vehicle), and FIG. It is a side perspective view (figure seen from the vehicle upper part slanting left front).

  As shown in FIGS. 1 and 2, the silencer support structure of this embodiment is configured so that a substantially cylindrical silencer 2 is arranged in the longitudinal direction in the longitudinal direction behind the rear suspension cross member 1 below the rear part of the vehicle body. The vehicle is arranged in a horizontal orientation in the vertical direction in FIG. 1 and in a direction perpendicular to the paper surface in FIG. 2, and is a vehicle traveling direction (a direction from right to left in FIG. When viewed from the right to the left), a point on the left side (the lower side in FIG. 1, the front side in the direction perpendicular to the plane of FIG. 2) and the vehicle traveling direction, which is the other side in the vehicle width direction. Suspended and supported on the vehicle side (side rail) by hangers 3, 4 and 5 at a total of 3 points on the end wall on the right side (upper side in FIG. 1, the direction perpendicular to the paper surface in FIG. 2) is doing.

  The silencer 2 is composed of a cylindrical body wall portion 6 whose main body casing is made of a plate material and substantially flat end wall portions 7 and 8 at both ends made of a plate material formed separately from the body wall portion 6. An exhaust inlet portion 9 and an exhaust outlet portion 10 are arranged substantially on the horizontal center line of the end wall portion 7 on the end wall portion 7 on one end side in the direction (left side as viewed in the vehicle traveling direction). The exhaust outlet portion 10 is provided at the rear side in the vehicle front-rear direction (right side in FIG. 1 and right side in FIG. 2) and the front side in the vehicle front-rear direction (left side in FIG. 1, left side in FIG. 2). The exhaust inlet section 9 is connected to an upstream exhaust pipe 11 extending from the front side in the vehicle front-rear direction in succession to an exhaust pipe (not shown) downstream of the engine catalyst mounted on the front of the vehicle. 10 is connected to a downstream exhaust pipe 12 as a tail pipe that is curved and dives under the upstream exhaust pipe 11 and extends rearward in the vehicle longitudinal direction through the outside in the vehicle width direction than the upstream exhaust pipe 11. A diffuser 13 is connected to the rear end of the pipe 12.

  The upstream exhaust pipe 11 is bent so as to straddle the rear suspension cross member 1 extending in the vehicle width direction below the rear part of the vehicle body, descends obliquely downward from the position straddling the suspension cross member 1, and is curved to be a silencer. 2 is extended to be connected.

  As shown in FIG. 3, the silencer 2 has end wall portions 7 and 8 (only the end wall portion 7 on one end side is shown, but the same applies to the end wall portion 8 on the other end side. ) Is folded so that a ring-shaped joint 14 is formed on the side of the body wall 6, and the edge of the body wall 6 is fitted into the ring-shaped joint 14 of the seam Are joined together to form a fold joint 15.

  As shown in FIGS. 1 to 12, the silencer 2 has an exhaust gas at the upper edge of the left end wall 7 that is one end side in the vehicle width direction where the exhaust inlet portion 9 and the exhaust outlet portion 10 are provided. A heat shield plate 20 that covers the vicinity of the connection portion of the upstream exhaust pipe 11 to the exhaust inlet portion 9 from above is fixed (welded) to a portion located directly above the outlet portion 10, and the upper surface of the heat shield plate 20. The hanger 3 is supported at a position closer to the rear of the hanger 3 by suspending and supporting one upper end side on the left side, which is one end side in the vehicle width direction, and a bar-shaped silencer side bracket 31 for the hanger is fixed to that position ( Welded). As shown in FIG. 6, the base portion of the silencer side bracket 31 is fixed on the heat shield plate 20 at a distance from the helix fold joint portion 15 of the left end wall portion 7 of the silencer 2.

  On the other hand, the support positions of the hangers 4 and 5 for supporting the two ends of the right end wall portion 8 which is the other end in the vehicle width direction are set to the front and rear sides in the vehicle front-rear direction. The bar-shaped silencer side brackets 41 and 51 are directly fixed (welded) to the end wall portion 8 of the silencer 2.

  The three hangers 3, 4, 5 for supporting the silencer in a suspended manner are each a mount rubber 32, 42, 52 that is an elastic body, and a silencer that is a support rod for suspending the mount rubber 32, 42, 52. It comprises side brackets 31, 41, 51 and a vehicle body side bracket (not shown) attached to the vehicle body side (side rail).

  The heat shield 20 has a three-dimensional shape, and as shown in FIGS. 1 and 6, the vehicle front-rear direction on the base end side (near the VV cross section in FIG. 6) fixed to the silencer 2. The width dimension of the upstream exhaust pipe 11 is formed so as to cover the vicinity of the connection portion of the upstream exhaust pipe 11 from the upper side. 3. As shown in FIG. 7 and the like, the upper side which is the back side (end wall side inner surface) of the top fold of the top fold joint portion 15 of the left end wall portion 7 which is one end side in the vehicle width direction. It is welded to the lower surface of the edge at three locations.

  As shown in FIG. 8 and the like, the heat shield plate 20 has a curved cross-sectional shape as viewed in the vehicle width direction, and is located near the connection portion to the exhaust inlet portion 9 of the upstream exhaust pipe 11 of the silencer side bracket 31. The front edge in the vehicle front-rear direction that does not overlap the upstream exhaust pipe 11 in a plan view of the intermediate portion where the welded portion is located (near the WW cross section in FIG. 6) guides the traveling wind to the upper surface of the heat shield plate 20. Then, it falls downward so as to contact the rear silencer side bracket 31, and a region including the periphery of the edge sinks downward to form a step-down portion 21.

  In the silencer support structure of this embodiment, the heat shield plate 20 is directly fixed to the silencer 2, the hanger silencer side bracket 31 is fixed to the heat shield plate 20, and the silencer side bracket 31 is attached via the heat shield plate 20. By being supported, it is possible to prevent the mount rubber 32 of the hanger 3 from being thermally deteriorated due to the temperature rise of the upstream exhaust pipe 11.

  And since the heat shield 20 is supported by the silencer side bracket 31 in such a manner that it directly receives the suspension load of the silencer 2 and is not free, it can be prevented that the heat shield 20 becomes a new vibration source.

  Further, the heat shield plate 20 is fixed to the silencer 2 at the surface of the base end portion having a wide width, has a three-dimensional shape and has high surface rigidity, and is a vehicle on the base end portion side fixed to the silencer 2. Since the width dimension in the front-rear direction is relatively large and the width dimension becomes smaller as it is closer to the free end on the outer side in the vehicle width direction, the vibration itself can be suppressed. Further, the heat shield plate 20 is firmly fixed on the surface of the shell fold joint portion 15 having the strength and rigidity of the end portion of the body casing 6 of the silencer 2, so that the heat shield plate 20 and the hanger 3 are firmly supported. It can be.

  Further, in this silencer support structure, the heat shield 20 has a curved cross-sectional shape as viewed in the vehicle width direction, and does not overlap the upstream exhaust pipe in plan view in the vicinity of the connection portion to the exhaust inlet portion 9 of the upstream exhaust pipe 11. The front edge in the vehicle front-rear direction is lowered downward, and the region including the periphery of the edge sinks downward to form the stepped-down portion 21, so that the silencer side bracket for the hanger is actively provided It is possible to improve the cooling performance of the silencer bracket 31 by guiding to 31 and reduce the heat transmitted from the silencer 2 that itself becomes a high temperature state to the mount rubber 32 of the hanger 3 through the heat shield plate 20 through the silencer bracket 31. And the heat load to the hanger 3 can be suppressed. In addition, the silencer side bracket 31 is separated from the end wall portion 7 of the silencer 2, that is, the helix fold joint portion 15, so that the heat of the silencer 2 is directly applied to the bracket 31. Without being transmitted, the thermal load transmitted to the mount rubber 32 via the bracket 31 can be reduced.

  In the above-described embodiment, after the upstream exhaust pipe 11 straddles the suspension cross member 1, the silencer 2 is lowered at an angle from a high position, but the present invention is not limited to this. Moreover, as a silencer, a downstream exhaust pipe may be arrange | positioned at the both sides of a vehicle width direction.

It is a top view of the silencer concerning the embodiment of the present invention. It is a side view (figure seen from the one end side of a vehicle width direction) of a silencer in an embodiment of the present invention. It is sectional drawing of the vehicle width direction one end side upper part of the silencer in embodiment of this invention. It is a rear view (figure seen from vehicle back) of a silencer concerning an embodiment of the present invention. It is an end side bottom view of the silencer concerning the embodiment of the present invention. FIG. 2 is an enlarged detail view of a T portion in FIG. 1. It is VV sectional drawing (part) of FIG. It is WW sectional drawing (part) of FIG. It is the one end side perspective view of the silencer concerning the embodiment of the present invention (figure seen from the vehicle upper part slanting left rear). It is the one end side perspective view of the silencer concerning the embodiment of the present invention (figure seen from the vehicle upper part slanting left front). It is the one end side perspective view of the silencer concerning the embodiment of the present invention (figure seen from the vehicle lower part slanting left front). It is the one end side perspective view of the silencer concerning the embodiment of the present invention (figure seen from the vehicle upper part slanting left front).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Suspension cross member 2 Silencer 3, 4, 5 Hanger 6 Trunk wall part 7, 8 End wall part 9 Exhaust inlet part 10 Exhaust outlet part 11 Upstream exhaust pipe 12 Downstream exhaust pipe 14 Ring-shaped junction 15 Flap joint 20 Heat shield 21 Step-down part 31, 41, 51 Silencer side bracket 32, 42, 52 Mount rubber

Claims (5)

A silencer support structure in which a substantially cylindrical silencer is disposed below a rear part of a vehicle body in a lateral orientation with a longitudinal direction substantially in the vehicle width direction, and is hung and supported by a hanger at both ends of the silencer,
The silencer is provided on an end wall portion at one end in the vehicle width direction so that an exhaust inlet portion and an exhaust outlet portion are disposed so that an exhaust inlet portion is rearward in the vehicle front-rear direction and an exhaust outlet portion is forward in the vehicle front-rear direction. An upstream exhaust pipe extending from the front side in the vehicle front-rear direction is connected to the exhaust inlet portion, and the exhaust outlet portion goes under the upstream exhaust pipe and passes outside in the vehicle width direction from the upstream exhaust pipe. A downstream exhaust pipe extending rearward in the vehicle longitudinal direction is connected,
The upper edge of the end wall portion on one end side in the vehicle width direction where the exhaust inlet portion and the exhaust outlet portion of the silencer are provided covers the vicinity of the connection portion of the upstream exhaust pipe to the exhaust inlet portion from above. A silencer support structure, wherein a heat plate is fixed, and the silencer side bracket for the hanger is fixed to the upper surface of the heat shield plate. The silencer is composed of a cylindrical body wall part whose main body casing is made of a plate material and substantially flat end wall parts at both ends made of a plate material formed separately from the body wall part, and the end wall part is a peripheral edge The part is folded so as to form a ring-shaped joint on the side of the trunk wall, and the edge of the trunk wall is fitted and joined to the ring-shaped joint of the half-fold,
2. The silencer support structure according to claim 1, wherein the heat shield plate is fixed to a lower surface of the upper edge portion which is a back side of the upper edge portion of the end wall portion on one end side in the vehicle width direction. The heat shield plate has a curved cross-sectional shape when viewed in the vehicle width direction, and has an edge on the front side in the vehicle front-rear direction that does not overlap the upstream exhaust pipe in plan view in the vicinity of the connection portion of the upstream exhaust pipe to the exhaust inlet portion. The silencer support structure according to claim 1 or 2, wherein the portion is lowered downward. The heat shield plate has a three-dimensional shape, and the width dimension in the vehicle front-rear direction on the base end side fixed to the silencer is relatively large, and the width dimension is closer to the free end on the outer side in the vehicle width direction. 4. The silencer support structure according to claim 1, wherein the silencer support structure is formed to be small. The silencer support structure according to claim 1, wherein the upstream exhaust pipe is disposed across a suspension cross member extending in a vehicle width direction.

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