JP2009220769A - Vehicle body front part structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To satisfy a requirement that a catalyst is arranged close to an engine and a requirement that a crush stroke is secured in a frontal collision. <P>SOLUTION: A DPF vessel 40 is extended to an upper area of a trans-axle 24 connected to a lateral placement engine 22 in a vehicle body longitudinal direction while being adjacent to the upper area and adjacent to a side area of the engine 22. A second exhaust pipe 74 is connected to an exit of a front surface of the DPF vessel 40, and after the exhaust pipe 74 is extended to a central portion in the vehicle width direction and obliquely downwardly extended to a lower side, the pipe is bent by approximately 90°, passed below the engine 22 and rearwardly extended along a central axis of the vehicle body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a vehicle body front structure, and more particularly to the arrangement of exhaust system parts in an engine room.

  It is well known that purification of automobile exhaust gas is an important technical issue due to environmental problems, and exhaust gas purification depends largely on the catalyst means installed in the exhaust system. is there. Since such a purifying device requires heat to promote the catalytic reaction, a catalyst means is disposed upstream of the exhaust system in order to exhibit the purifying function at an early stage when it is cold.

  Patent Document 1 relates to a vehicle equipped with a gasoline engine, and in order to promote early activation of the catalyst at the time of engine startup with respect to so-called “lateral installation, rear exhaust” in which the engine is placed horizontally and exhausted from the rear surface of the engine. It is disclosed that the means is arranged close to the rear face of the engine. Specifically, Patent Document 1 proposes to arrange the catalyst means along the rear surface of the horizontally mounted engine.

  Patent Document 2 relates to a vehicle equipped with a diesel engine, and a DPF (diesel particulate filter) regenerates the DPF by burning the soot accumulated on the filter and burning it away with a catalyst. It is preferable to arrange them close to each other, and from this, Patent Document 2 proposes to arrange the DPF along the rear surface of the horizontally placed engine.

  In Patent Document 3, in order to reduce the yaw moment of inertia of a vehicle equipped with a rotary engine and improve steering stability, the catalyst is placed in front of the engine when the engine is mounted at a position retracted to a position where it interferes with the dash panel. Propose to arrange.

JP 2007-146681 A JP 2006-70878 A JP 2003-326981 A

  Exhaust gas purification standards are becoming stricter year by year, and the fact is that the degree of dependence on the catalyst to cope with this is increasing, and as a result, the catalyst tends to be larger. Therefore, as in Patent Documents 1 and 2, when a catalyst means such as DPF is disposed along the rear surface of the horizontally placed engine, the case for accommodating this catalyst is relatively hard and is accompanied by the retreat of the engine at the time of a frontal collision. Since the catalyst also moves backward, the problem remains that the crash stroke at the time of a frontal collision is effectively reduced.

  On the other hand, when the catalyst means is disposed in front of the engine as in Patent Document 3 in a horizontally placed and rear exhaust engine, the exhaust pipe from the engine to the catalyst becomes long. Can no longer be prompted.

  An object of the present invention is to provide a vehicle body front part structure capable of satisfying a request for arranging a catalyst close to an engine and a request for ensuring a crash stroke at the time of a frontal collision.

According to the present invention, the above technical problem is
A reciprocating engine in which a transaxle is integrally connected to the end of the crankshaft between the left and right front side frames that extend forward from the dash panel is defined by the dash panel. In the vehicle body front structure mounted horizontally, extending along the direction,
A part of the exhaust pipe of the exhaust system connected to the rear surface of the reciprocating engine extends from the rear of the vehicle body to the front in the upper region of the transaxle and in the lateral region of the horizontal engine in the exhaust gas flow direction. This is accomplished by providing a vehicle body front structure which is later bent downward and then bent rearward and extending rearward in the lower region of the engine.

  As described in the prior art section, when a horizontally mounted engine employs rear exhaust, a catalyst is usually provided adjacent to the engine. Therefore, by arranging a part of the exhaust pipe adjacent to the side of the horizontally-exhausted exhaust engine and on the side thereof, it becomes possible to arrange the catalyst at the part. Not only can the catalyst be activated early, but also the problem of shortening the crash stroke during a frontal collision, which is a problem when the catalyst is placed adjacent to the rear of the engine, can be solved.

  According to a preferred embodiment of the present invention, the exhaust pipe located in the upper region of the transaxle and in the lateral region of the horizontally mounted engine is constituted by a catalyst container. Typically, the catalyst container is a diesel engine. It is a DPF container of an engine.

  In a preferred embodiment, a turbocharger is disposed adjacent to a rear surface of the horizontal engine, and the turbocharger includes a compressor and a centrifugal exhaust turbine, and the compressor and the exhaust turbine are The compressor is positioned on the opposite side of the transaxle, the exhaust turbine is positioned on the transaxle side, and the outlet of the exhaust turbine is disposed on the transformer. It is directed to the axle side. According to this, the direction of the exhaust gas discharged from the centrifugal exhaust turbine can be used as it is, and the exhaust gas can be guided to the catalyst container, and the length of the exhaust pipe between the exhaust turbine and the catalyst container can be minimized. To the limit. This effect is even more effective when the turbocharger is positioned in the center of the vehicle width direction in the engine room and the catalyst container is positioned in front of the rear end of the turbocharger when viewed from the side. .

  Further, in a preferred embodiment, a dash cross member extending between the left and right front side frames is provided on a front surface of the dash panel, and the dash cross member has a height level lower than that of the exhaust turbine and the catalyst container. It is arranged. According to this, even if a dash cross member effective for offset frontal collision is provided, the exhaust turbine, the catalyst container, and the dash cross member have different height levels in the vertical direction, so that these interferences can be avoided. Can do.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings.

  Referring to FIGS. 2 and 3, reference numeral 1 indicates a dash panel, and the vehicle compartment 2 and the engine room 3 are partitioned by the dash panel 1. The vehicle compartment 2 is provided with an instrument panel 4, a brake pedal 5, a steering handle, and the like. Reference numeral 6 denotes a front window.

  As can be seen from FIG. 1 when the engine room is viewed from above and FIG. 6 when the engine room is viewed from below, the lower part of the engine room 3 includes left and right fronts extending in the longitudinal direction of the vehicle body over the entire region of the engine room 3. Side frames 10 and 10 are disposed, and a dash cross member 11 extending along the dash panel 1 is disposed between the rear ends of the left and right front side frames 10 and 10 at the rear of the engine room 3. In addition, a sub-frame 12 extending in the vehicle width direction is disposed, and a steering device 14 including a steering rod and its drive unit is mounted on the sub-frame 12. The front end of the front side frames 10 and 10 is connected to a bumper reinforcement 15 via a crash can.

  Reference numeral 16 denotes a front wheel, and a suspension mechanism 18 for the front wheel 16 employs a strut suspension in which a shock absorber is disposed in a coil spring. As is known, this strut suspension has the advantage that the distance between the left and right suspension towers 20, 20 can be increased.

  1 to 3, the engine 22 is mounted in the engine room 3 with its crankshaft directed in the vehicle width direction. That is, the engine 22 is a horizontal reciprocating engine, and a transaxle 24 is connected to the rear end of the crankshaft of the engine 22 side by side in the vehicle width direction. The transaxle 24 includes a torque converter 26 connected to the crankshaft of the engine 22, followed by a multi-stage automatic transmission 28 having a planetary gear mechanism, and the engine via a differential gear 30 connected to the automatic transmission 28. The output is transmitted to the left and right front wheels 15.

  The engine 22 is a water-cooled four-cylinder engine, and the cooling water of the engine 22 is cooled by a radiator 34 fixed to a shroud panel between the front end portions of the front side frame 10.

  The horizontally placed engine 22 is sucked from the front surface 22a and exhausted from the rear surface 22b. That is, the engine 22 employs the front intake and the rear exhaust. The engine 22 is a diesel engine, and the engine 22 is supercharged by a turbocharger 38 with an intercooler 36, and a DPF container 40 is interposed in the exhaust system.

  The intake system of the engine 22 will be described. The intake system includes an air cleaner box 44, a compressor 46 of a turbocharger 38, an intercooler 36, and an intake manifold 48, which are arranged in that order from the upstream side. Outside air is supplied to the air cleaner box 44 through an air introduction pipe 50 (FIGS. 1 and 6), and the outside air introduced into the air cleaner box 44 is purified by a filter (not shown).

  The outside air purified in the air cleaner box 44 is supplied to the compressor 46 by the first intake pipe 52 (FIGS. 1 and 5) connecting the air cleaner box 44 and the compressor 46, and is compressed by the compressor 46. The outside air compressed by the compressor 46 is supplied to the intercooler 36 by the second intake pipe 54 (FIGS. 1 and 4) connecting the compressor 46 and the intercooler 36, and is cooled by the intercooler 36. The outside air cooled by the intercooler 36 is supplied to the intake manifold 48 by a third intake pipe 56 (FIG. 6) that connects the intercooler 36 and the intake manifold 48, and is filled in each cylinder in the intake stroke of each cylinder of the engine 22. Is done.

  Next, the exhaust system of the engine 22 will be described. In addition to the centrifugal type exhaust turbine 62 of the centrifugal type turbocharger 38 and the DPF (diesel particulate filter) in order from the engine 22 side, as well known, It consists of a second catalyst and a silencer. As shown in FIGS. 1 and 5, the turbocharger 38 includes a turbine 62 and a compressor 46 arranged along the longitudinal direction of the engine 22. The turbine 62 is located on the DPF container 40 side, and the compressor 46 is connected to the intercooler 36. Located on the side.

  Explaining the layout of the intake system, the rectangular parallelepiped air cleaner box 44 is disposed at the upper end of one side end of the front end of the engine room 3. The air introduction pipe 50 has an upstream end opening 50a that is flat in the vertical direction and elongated in the lateral direction (FIG. 1), and the upstream end opening 50a of the air introduction pipe 50 is shroud at the center in the vehicle width direction. It is disposed between the panel and the hood hood 66 and is opened forward (FIG. 2). The air introduction pipe 50 extends in the vehicle width direction from the upstream end opening 50a (FIG. 1), and is connected to the inner side surface 44a in the vehicle width direction of the air cleaner box 44 located at the upper end portion of the one side end portion described above. Has been.

  Next, the first intake pipe 52 that connects the air cleaner box 44 and the compressor 46 will be described. First, the compressor 46 is disposed adjacent to the rear surface 22 b of the engine 22. The upstream end of the first intake pipe 52 is connected to the upper surface 44 b of the air cleaner box 44. The first intake pipe 52 extends from the air cleaner box 44 to the other end portion in the vehicle width direction, and then extends rearward. The first intake pipe 52 is adjacent to the end surface of the engine 22 and extends outside the vehicle width direction in the rear surface 22b of the engine 22. And is connected to the compressor 46 by extending in the vehicle width direction along the rear surface 22b adjacent to the upper end of the rear surface 22b (FIG. 1). That is, the shape of the first intake pipe 52 will be described in plan view of the engine room 3. The first intake pipe 52 extends from the air cleaner box 44 located on one side of the front end of the engine room 3 to the other side in the vehicle width direction. The vehicle width direction along the rear surface 22b of the engine 22 after extending in the vehicle width direction toward the rear and then bending at a substantially right angle. It has a shape extending in the direction. Further, when the first intake pipe 52 is viewed from the side, it is disposed in substantially the same plane adjacent to the upper end region of the engine room 3, that is, the lower surface of the hood hood 66.

  Next, the second intake pipe 54 that connects the compressor 46 and the intercooler 36 will be described. First, the intercooler 36 has a front end angle on the other side opposite to the air cleaner box 44 at the front end of the engine room 3. It is arrange | positioned at the corner | angular part and is arrange | positioned at the lower end part in the front-end corner | angular part of the engine room 3 (FIG. 1, FIG. 6). More specifically, the intercooler 36 is disposed in a lower area outside the front end of the front side frame 10 in the vehicle width direction.

  The second intake pipe 54 extends upward from the compressor 46, then extends in the vehicle width direction along the rear surface 22b of the engine 22 and adjacent to the rear surface 22, and then directly below the first intake pipe 52 in the first direction. The side of the engine room 3 extends forward side by side with the intake pipe 52, and extends obliquely downward immediately after passing the front surface 22a of the engine 22 and is connected to the intercooler 36 (FIG. 6).

  Next, the third intake pipe 56 that connects the intercooler 36 and the intake manifold 48 will be described. First, the intake manifold 48 is attached to the front surface 23a of the engine 22 because the engine 22 employs a front intake system. ing. The third intake pipe 56 extends from the intercooler 36 inward in the vehicle width direction and then bends upward to be connected to the intake manifold 48.

  Explaining the layout of the exhaust system, the DPF container 40 is disposed above the transaxle 24 and adjacent thereto (FIG. 5), and is disposed adjacent to the side region of the engine 22 (FIG. 5). 1) The DPF container 40 extends in the longitudinal direction of the vehicle body. The DPF container 40 has a cylindrical shape, and the exhaust gas enters from the rear surface side of the DPF container 40 and flows out from the front surface side of the DPF container 40.

  The outlet of the exhaust manifold 70 fastened to the rear surface 22b of the engine 22 is formed to be shifted to the transaxle 24 side (FIG. 1). A centrifugal exhaust turbine 62 is attached adjacent to the outlet of the exhaust manifold 70. Further, the outlet of the exhaust turbine 62 is directed outward in the vehicle width direction and toward the DPF container 40, and the exhaust turbine 62 is substantially directly connected to the exhaust manifold 70.

  As described above, the DPF container 40 is disposed above the transaxle 24, but its height is positioned at substantially the same level as the exhaust turbine 62. Further, the rear end of the DPF container 40 is positioned forward of at least the rear end of the exhaust turbine 62, and preferably is positioned forward of the outlet of the exhaust turbine 62. The rear end face is connected by a first exhaust pipe 72. A second exhaust pipe 74 is connected to the outlet of the front surface of the DPF container 40. The second exhaust pipe 74 bends approximately 90 degrees after extending obliquely downward toward the center in the vehicle width direction and downward. And extends rearwardly below the engine 22 and along the center axis of the vehicle body. A second catalyst, a silencer, and the like are installed in the second exhaust pipe 74. An oxidation catalyst may be accommodated in the DPF container 40. In this case, the second catalyst may be a reduction catalyst.

  As described above, according to the embodiment, the DPF container 40 including a relatively large and hard case is disposed in the upper region of the transaxle 24 connected to the horizontal engine 22, and from this, Since it is located adjacent to the rear exhaust engine 22, the inlet of the DPF container 40 can be located at a position adjacent to the exhaust manifold 70 (FIG. 1). From this, the DPF container 40 can be brought close to the engine 22 to achieve early activation at the start, and the presence of the DPF container 40 can be eliminated from the rear of the engine 22. It can be avoided that the crash stroke is shortened due to the existence behind.

  In the embodiment, the turbocharger 38 is mounted, and the turbocharger 38 is assembled to the engine 22 so that the centrifugal exhaust turbine 62 and the compressor 46 are aligned in the vehicle width direction (FIG. 5). That is, the exhaust turbine 62 and the compressor 46 are located side by side along the rear surface 22b of the horizontally mounted engine 22, and from this, the outlet of the centrifugal exhaust turbine 62 is directed outward in the vehicle width direction and toward the DPF container 40 side. Furthermore, since the exhaust turbine 62 and the DPF container 40 are disposed at substantially the same height level, the exhaust turbine 62 and the inlet of the DPF container 40 located on the side of the exhaust turbine 62 are in the vehicle width direction. Therefore, the exhaust turbine 62 and the DPF container 40 can be connected to each other with a relatively short pipeline and a short distance. Thus, the exhaust gas immediately after exiting the engine 22 can be introduced into the DPF container 40 without hindering the exhaust flow.

  Further, since the outlet of the exhaust manifold 70 is set so as to be shifted from the center in the longitudinal direction of the exhaust manifold 70 to the DPF container 40 side, the exhaust turbine 62 and the compressor 46 can be mounted in the center in the vehicle width direction, and the engine An exhaust turbine 62 and a compressor 46 can be disposed on the upper portion of 22. From this, the turbocharger 38 can be disposed facing the center and upper part of the dash panel 1 in the vehicle width direction. As a result, even if the turbocharger 38 moves backward due to a frontal collision and interferes with the dash panel 1, Even if the dash panel 1 is deformed by the turbocharger 38, it is between the left and right front seat occupants and is not at the feet of the front seat occupants, so that the influence on the lower limbs of the front seat occupants can be avoided.

  Further, in the embodiment, a frame structure is adopted in which a dash cross member 11 is provided along the lower portion of the dash panel 1 so as to improve the adaptability in the offset frontal collision. As can be seen from FIG. Since the DPF container 40 and the turbocharger 38 are disposed at a height level higher than 11, the exhaust system including the DPF container 40 does not interfere with the dash cross member 11. Similarly, as can be seen from FIG. 2, since the rear end portion of the transaxle 32, that is, the differential gear 38 is at a lower level than the dash cross member 11, it is possible that the differential gear 38 interferes with the dash cross member 11 during a frontal collision. Absent.

It is the figure which looked at the engine room from upper direction along the II line of FIG. It is the figure which looked at the engine room from right to left direction along the II-II line of FIG. It is the figure which looked at the engine room from the left to the right direction. It is the figure which looked at the engine room from the front. It is the figure which looked at the engine room from back along the VV line of FIG. It is the figure which looked at the engine room from the lower part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Dash panel 2 Car compartment 3 Engine room 10 Front side frame 11 Dash cross member 12 Sub frame 22 Engine 22a Engine front surface 22b Engine rear surface 24 Transaxle 26 Torque converter 28 Automatic transmission 38 Turbocharger 40 DPF container 42 Intake system 44 Air cleaner box 46 Compressor (turbocharger)
60 Exhaust system 62 Exhaust turbine (turbocharger)
70 Exhaust manifold

Claims (5)

A reciprocating engine in which a transaxle is integrally connected to the end of the crankshaft between the left and right front side frames that extend forward from the dash panel is defined by the dash panel. In the vehicle body front structure mounted horizontally, extending along the direction,
A part of the exhaust pipe of the exhaust system connected to the rear surface of the reciprocating engine extends from the rear of the vehicle body to the front in the upper region of the transaxle and in the lateral region of the horizontal engine in the exhaust gas flow direction. A vehicle body front part structure that is bent downward and then bent rearward and extends rearward in a lower region of the engine.   The vehicle body front structure according to claim 1, wherein an exhaust pipe located above the transaxle and in a side area of the horizontally mounted engine is constituted by a catalyst container.   A turbocharger is disposed adjacent to the rear surface of the horizontally mounted engine, the turbocharger having a compressor and a centrifugal exhaust turbine, and the compressor and the exhaust turbine are arranged in the vehicle width along the rear surface of the engine. Arranged in a direction, the compressor is located on the opposite side of the transaxle, the exhaust turbine is located on the transaxle side, and the outlet of the exhaust turbine is directed to the transaxle side, The vehicle body front part structure according to claim 1 or 2.   The front surface of the dash panel is provided with a dash cross member extending between the left and right front side frames, and the dash cross member is disposed at a lower level than the exhaust turbine and the catalyst container. Item 4. The vehicle body front structure according to Item 3.   The turbocharger is located in the vehicle width direction center in the engine room, and the catalyst container is located in front of the rear end of the turbocharger when viewed from the side. The vehicle body front structure according to one item.

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