JP6146399B2 - Engine intake system - Google Patents

Description

  The present invention relates to an intake device for an engine.

  Conventionally, when an engine is arranged horizontally in an engine room at the front of the vehicle so that the cylinder row direction faces the vehicle width direction, the engine is generally provided so that the intake manifold is positioned on the front side of the vehicle. It is. In order to reduce the weight, the intake manifold is made of synthetic resin.

  The intake manifold includes an intake pipe connected to the intake port of the engine cylinder head, a surge tank connected to the upstream end of the intake pipe, and an intake introduction pipe connected to the upstream end of the surge tank. And have. A throttle body for adjusting the amount of intake air supplied to the intake manifold is connected to the upstream end portion of the intake intake pipe.

  2. Description of the Related Art Conventionally, in a vehicle equipped with such a horizontally mounted engine, when a frontal collision occurs, the intake manifold is destroyed so as to be flattened, and the impact of the collision is absorbed by the destruction.

  Patent Document 1 discloses a structure in which the intake manifold pipe wall of the intake manifold and the intake pipe tube wall are integrally formed by a common wall, thereby increasing the rigidity of the intake manifold.

  In this structure, since the intake manifold has high rigidity, it is difficult to break the intake manifold so as to be flattened. Therefore, by forming a fragile part on the common wall and breaking the fragile part at the time of a frontal collision, the throttle body is separated from the intake manifold and the engine is moved backward smoothly so as to effectively absorb the shock. I have to.

JP 2013-249815 A

  By the way, when a so-called direct injection engine that directly injects fuel into the combustion chamber is adopted as a horizontal engine, a fuel distribution pipe (so-called fuel rail) that distributes the fuel to the injectors of each cylinder extends in the cylinder row direction. In this way, the fuel distribution pipe and the intake manifold are in close proximity to each other.

  Therefore, at the time of a frontal collision of the vehicle, a radiator arranged in front of the intake manifold may collide with the intake manifold, and the impact of the collision may cause the intake manifold to be displaced rearward, causing the intake manifold to interfere with the fuel distribution pipe.

  In the case of such an engine structure, an intake manifold is provided so that the intake pipe, surge tank, and intake intake pipe are arranged in this order from the upper side to the lower side. It is desirable to squeeze the tube widely into a flat shape to absorb the impact.

  However, in this case, the throttle body connected to the intake intake pipe tends to protrude toward the front side of the vehicle relative to the intake manifold, and the throttle body is attached to the throttle body before the radiator collides with the intake manifold at the time of frontal collision of the vehicle. There is a possibility that the intake manifold may interfere with the fuel distribution pipe due to collision and displacement of the intake manifold together with the throttle body toward the rear side of the vehicle. Therefore, it is necessary to solve this problem.

  Note that the engine structure described in Patent Document 1 is such that the throttle body is positioned on the rear side of the front end portion of the intake manifold, and the radiator collides with the throttle body at the time of frontal collision of the vehicle. In this case, the entire engine is moved rearward by colliding with the intake manifold, and the above problem is not solved at all.

  The present invention has been made in view of the above circumstances, and a frontal collision of a vehicle when a throttle body is connected to an intake introduction pipe of the intake manifold so as to protrude toward the front side of the vehicle from the intake manifold. It is an object of the present invention to provide an engine intake device capable of suppressing the throttle body from sometimes pressing the intake manifold and interfering with the fuel distribution pipe.

In order to solve the above-described problems, the present invention is an engine intake device that is disposed horizontally in an engine room at the front of a vehicle so that the cylinder row direction faces the vehicle width direction, and is on the vehicle front side. A synthetic resin intake manifold disposed on the front side of the engine; a throttle body connected to the intake manifold for adjusting the amount of intake air supplied to the intake manifold; and the cylinder between the engine and the intake manifold A fuel distribution pipe that extends in the column direction and supplies fuel to a fuel injection valve corresponding to each cylinder of the engine; and the intake manifold is connected to an intake port of a cylinder head of the engine; a surge tank connected to the upstream end of the intake pipe, an intake inlet pipe connected to the upstream end of the surge tank, or By the intake pipe is fixed to the cylinder head, is supported in a cantilever state to the cylinder head, the throttle body, said intake air introduction pipe so pushed out on the front side of the vehicle than the intake manifold A weakened portion is formed near the upstream end of the intake introduction pipe, connected to the upstream end, and the intake introduction pipe is formed near the intake introduction pipe on the cylinder head side in the event of a frontal collision of the vehicle. An engine intake device is provided , wherein a load receiving member for receiving a downstream portion of the fragile portion is provided .

  In the present invention, “in the vicinity of the upstream end portion of the intake introduction pipe” means a portion slightly downstream of the upstream end portion of the intake introduction pipe. The “fragile portion” means a portion that can accelerate the breakage of the intake manifold by inputting an external force to the throttle body.

According to the present invention, at the time of a frontal collision of the vehicle, a member (for example, a radiator or the like) arranged on the front side of the throttle body collides with the throttle body before colliding with the intake manifold. Due to the impact of the collision with the throttle body, the fragile portion is easily and quickly broken, so that the throttle body is prevented from pressing the intake manifold toward the vehicle rear side. Therefore, it is possible to suppress the intake manifold from being displaced rearward and interfering with the fuel distribution pipe (fuel rail). Further, the impact of the collision is absorbed by the breakage of the fragile portion. Since the degree of breakage of the fragile portion changes according to the amount of the collision partner entering the vehicle, the impact can be appropriately absorbed according to the amount of the approach.
In addition, a knock sensor for detecting knocking is usually attached to the cylinder block. However, in the above-mentioned cantilever support state, the engine cylinder block and the intake pipe are not directly connected. It is possible to prevent the nearby rigidity from changing. Therefore, knocking can be accurately detected by the knock sensor. In addition, it is possible to suppress vibration from being input from the cylinder block side to a throttle valve that requires high opening / closing accuracy to control engine output.
In addition, since the load receiving member receives the intake pipe at the time of a frontal collision of the vehicle, it is possible to suppress the movement of the intake pipe at the time of a frontal collision and to actively generate a shearing force at the fragile part. Can be broken. By promoting the breakage of the fragile portion, it is possible to promote the absorption of impact due to the breakage of the fragile portion.

  In the present invention, the intake manifold is composed of a rear divided body on the side close to the engine and a front divided body on the side far from the engine, and the strength of the front divided body is that of the rear divided body. It is preferably smaller than the strength.

  According to this configuration, when the intrusion amount of the collision partner with respect to the host vehicle is large, the fragile portion is completely broken, the throttle body is dropped from the intake intake pipe, and the radiator and the like collide with the intake manifold. However, since the front divided body is easily deformed, the impact of the collision is absorbed by the front divided body, and the deformation of the rear divided body is suppressed. Therefore, the intake manifold can be prevented from interfering with the fuel distribution pipe.

  In the present invention, it is preferable that the fragile portion is formed by reducing a wall thickness in the vicinity of an upstream end portion of the intake air introduction pipe.

  According to this configuration, the vulnerable portion can be configured with a simple configuration.

  In the present invention, it is preferable that the intake pipe, the surge tank, and the intake introduction pipe are arranged in this order from the upper side to the lower side.

  According to this configuration, a radiator or the like can collide with the intake pipe, the surge tank, and the intake introduction pipe at the time of a frontal collision of the vehicle, and the vehicle front side portion is crushed into a flat shape to reduce the impact of the collision. It can be absorbed effectively.

  As described above, according to the present invention, when the throttle body is connected to the intake inlet pipe of the intake manifold so as to protrude toward the vehicle front side of the intake manifold, the throttle body By pressing the manifold, it is possible to suppress the intake manifold from interfering with the fuel distribution pipe.

1 is a perspective view showing an engine and an intake device thereof according to an embodiment of the present invention. It is a perspective view which shows the intake device in FIG. It is the side view which looked at the air intake apparatus shown in FIG. 2 from the D direction. FIG. 4 is a cross-sectional view showing the intake device shown in FIG. 3 in a state where the intake device is cut at the center in the cylinder row direction. FIG. 3 is a perspective view of a front divided body of the intake manifold shown in FIG. 2 as viewed from the inside (vehicle rear side). It is a perspective view which shows the gas channel | path structural member for forming a gas introduction flow path. FIG. 3 is a perspective view showing a structure in the vicinity of a load receiving member and a load transmission portion in FIG. 2. FIG. 4 is a side view sequentially illustrating how the intake manifold illustrated in FIG. 3 is broken at the time of a frontal collision of a vehicle, (a) is a diagram illustrating the moment when a radiator collides with a throttle body, and (b) is a result of a collision impact. The figure which shows the state which the throttle body displaced to the vehicle rear side, (c) is a figure which shows the state which the vehicle front side part of the surge tank and the intake air intake pipe was crushed by the impact of the collision.

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

  The engine 4 (see FIG. 1) in the embodiment of the present invention is a so-called direct injection engine that directly injects fuel into a combustion chamber, and is an in-line four-cylinder engine. The engine 4 is a horizontally mounted engine that is disposed horizontally in the engine room at the front of the vehicle so that the cylinder row direction faces the vehicle width direction.

  The engine 4 includes a cylinder head 40 in which four intake ports and four exhaust ports (both not shown) are formed, and a cylinder block 41 provided on the lower side of the cylinder head 40.

  In the following description, the direction A shown in FIG. 1 is the vehicle front-rear direction, the direction B is the vertical direction, and the direction C is the cylinder row direction (vehicle width direction).

  As shown in FIG. 1, an intake device 1 for an engine according to this embodiment includes an intake manifold 2 and a fuel distribution pipe 3.

  The intake manifold 2 is located on the vehicle front side of the engine 4.

  The fuel distribution pipe 3 (so-called fuel rail) is disposed between the engine 4 and the intake manifold 2 so as to extend in the cylinder row direction C, and is fixed to the front surface of the engine 4 (surface on the vehicle front side). The fuel distribution pipe 3 distributes fuel to the injectors of the cylinders of the engine 4. The fuel distribution pipe 3 and the intake manifold 2 are close to each other as shown in FIG.

  Hereinafter, the intake manifold 2 will be described in detail.

  As shown in FIG. 2, the intake manifold 2 includes four intake pipes 5, a surge tank 6, and an intake introduction pipe 7. The intake manifold 2 is made of a synthetic resin material for weight reduction.

  As shown in FIG. 3, the intake pipe 5, the surge tank 6, and the intake introduction pipe 7 are composed of a rear divided body 20 on the side close to the engine 4 and a front divided body 21 on the side far from the engine 4. ing. The rear part 20 and the front part 21 are integrated by vibration welding.

  That is, the rear divided body 20 is configured by portions of the intake pipe 5, the surge tank 6, and the intake introduction pipe 7 on the side close to the engine 4. On the other hand, the front divided body 21 is constituted by portions of the intake pipe 5, the surge tank 6, and the intake introduction pipe 7 on the side far from the engine 4.

  The wall thickness of the front divided body 21 is smaller than the wall thickness of the rear divided body 20. For example, the wall thickness of the front divided body 21 is 2 mm, and the wall thickness of the rear divided body 20 is 3.5 mm. Thereby, the strength of the front divided body 21 is smaller than the strength of the rear divided body 20.

  As shown in FIG. 3, the boundary line 12 between the front divided body 21 and the rear divided body 20 is located at the center in the vehicle longitudinal direction A in the intake pipe 5 and the surge tank 6. The same applies to the portion extending from the downstream end of the intake pipe 7 to the center in the longitudinal direction.

  On the other hand, the boundary line 12 is inclined so as to gradually approach the front surface of the intake introduction pipe 7 as it approaches the upstream end from the longitudinal center of the intake introduction pipe 7. The boundary line 12 reaches the front surface (the front surface of the vehicle) of the intake air introduction pipe 7 in the vicinity of the upstream end portion of the intake introduction pipe 7 (a portion slightly downstream from the upstream end portion).

  That is, in the portion extending from the vicinity of the upstream end portion of the intake air introduction pipe 7 to the upstream end portion, both the portion close to the engine 4 and the portion far from the engine 4 (the entire circumferential direction of the intake air introduction tube 7) are the rear divided body 20. It is configured as.

  As shown in FIG. 1, the downstream ends of the four intake pipes 5 are respectively connected to four intake ports provided in the cylinder head 40 of the engine 4. The intake pipe 5 supplies a mixture of fresh air, EGR (Exhaust Gas Recirculation) gas, and blow-by gas to the intake port.

  By fixing the intake pipe 5 to the cylinder head 40, the intake manifold 2 is supported by the cylinder head 40 in a cantilever state. That is, the surge tank 6 and the intake pipe 7 are indirectly supported by the engine 4 via the intake pipe 5 and are not directly supported by the engine 4.

  A knock sensor for detecting knocking is attached slightly above an oil separator 16 described later on the front surface (front surface of the vehicle) of the cylinder block 41. In the cantilever support state, the cylinder block 41 of the engine 4 and the intake air introduction pipe 7 are not directly connected, so that the rigidity of the cylinder block 41 in the vicinity of the position where the knock sensor is attached is prevented from changing. Therefore, knocking can be accurately detected by the knock sensor. Further, it is possible to suppress vibration from being input from the cylinder block 41 side to a throttle valve 11a, which will be described later, which requires high opening / closing accuracy to control the output of the engine 4.

  As shown in FIGS. 1 and 2, the surge tank 6 extends in the cylinder row direction C, and is formed such that the width in the vertical direction B gradually decreases from the center in the cylinder row direction C toward both ends. ing. As shown in FIGS. 3 and 4, the front surface (surface on the vehicle front side) of the surge tank 6 has an arc shape that is convex toward the vehicle front side when viewed from the cylinder row direction C.

  Upstream end portions of the four intake pipes 5 are connected to the upper surface of the surge tank 6. Connection portions between the surge tank 6 and the four intake pipes 5 are arranged at regular intervals in the cylinder row direction C on the upper surface of the surge tank 6.

  A downstream end portion of the intake pipe 7 is connected to a lower end portion of the central portion of the surge tank 6 in the cylinder row direction C. The surge tank 6 temporarily stores a mixture of fresh air, EGR gas, and blow-by gas introduced from the intake introduction pipe 7, and further mixes the mixture to supply it to the four intake pipes 5. A gas inlet 6c for introducing EGR gas is formed in the upper portion of the outer wall of the surge tank 6 on the vehicle front side. The gas introduction port 6c is located at an upstream end of a gas introduction flow path 8 to be described later.

  As shown in FIGS. 1 to 4, the front surface of the surge tank 6 (surface on the vehicle front side) is provided with a protrusion 60 that protrudes from the front surface toward the vehicle front side. The protrusion 60 is provided at a position where a radiator (not shown) arranged in front of the intake manifold 2 (front side of the vehicle) can collide with a frontal collision of the vehicle.

  One protrusion 60 is provided on each side of the central portion of the surge tank 6 in the cylinder row direction C. Each protrusion 60 is provided at a position closer to the center (close to the center) than the end of the surge tank 6 in the cylinder row direction C.

  The shape and size of the protrusion 60 allow the radiator disposed in front of the intake manifold 2 to collide with the frontal collision of the vehicle, and does not substantially increase the strength of the surge tank 6 (reinforcement). No) and shape and size.

  In the example shown in FIGS. 1 and 2, the protrusion 60 is formed in a front constricted shape so that the dimensions (height and width) in the vertical direction B and the cylinder row direction C are smaller toward the vehicle front side. More specifically, it is formed in a tapered quadrangular frustum shape on the front side of the vehicle.

  In the example shown in FIGS. 1 and 2, the protrusion length of the protrusion 60 (the length in the vehicle longitudinal direction A) is the vertical direction of the surge tank 6 at the position where the protrusion 60 is provided in the cylinder row direction C. It is set to about 1/4 to 1/3 of the length of B, and is slightly larger than the protruding length (length in the vehicle front-rear direction A) of the portion 61a provided on the front surface of the surge tank 6 in the protruding portion 61 described later. (See FIGS. 3 and 4). The length in the vertical direction B and the cylinder row direction C of the root portion of the projection 60 (the boundary portion with the surge tank 6) is approximately the same as the projection length of the projection 60.

  The interior of the protrusion 60 is hollow, and the end of the protrusion 60 on the vehicle rear side is open to the internal space of the surge tank 6.

  As shown in FIG. 4, a gas introduction flow path 8 that guides EGR gas to an upstream portion of the intake introduction pipe 7 (inside the intake introduction pipe 7) is provided inside the intake manifold 2. The upstream end of the gas introduction channel 8 is connected to the downstream end of the EGR passage 9. The EGR passage 9 is a conduit that guides a part of the exhaust gas discharged from the exhaust port of the engine 4 to the gas introduction passage 8 via an EGR cooler and an EGR valve (both not shown).

  The gas introduction flow path 8 includes a raised portion 61 formed in a vehicle front side portion (front divided body 21) of the surge tank 6 and the intake introduction pipe 7, and a guide portion 10b of the gas flow path constituting member 10 described later. It is a channel wall. The raised portion 61 is formed on the front surface of the surge tank 6 and the front surface of the intake air intake pipe 7 so as to protrude from the respective front surfaces to the vehicle front side. The raised portion 61 is formed by the inner surface of the outer wall portion of the front divided body 21 bulging outward and the outer surface of the outer wall portion protruding outward.

  That is, as shown in FIG. 4, the gas introduction flow path 8 is formed between the raised portion 61 and the gas flow path constituting member 10 provided on the vehicle rear side of the raised portion 61. A space between the raised portion 61 and the gas flow path component 10 is a gas introduction flow path 8. The gas flow path component 10 is integrated with the surge tank 6 and the inner wall surface 7a (see FIG. 5) of the intake pipe 7 by vibration welding.

  As shown in FIGS. 1 and 2, the raised portion 61 is formed at the center portion of the surge tank 6 in the cylinder row direction C and across the front surface of the surge tank 6 and the front surface of the intake air intake pipe 7. The raised portion 61 has an upper raised portion 61 a raised from the front surface of the surge tank 6 and a lower raised portion 61 b raised from the front surface of the intake air introduction pipe 7. The upper raised portion 61a extends in the up-down direction B along the front surface of the surge tank 6, and the lower raised portion 61b extends in the up-down direction B along the front surface of the intake intake pipe 7, and these are continuous with each other. doing.

  As shown in FIGS. 3 and 4, the upper raised portion 61 a has a uniform protrusion length (length in the vehicle longitudinal direction A) from the front surface of the surge tank 6 over the entire vertical direction B. On the other hand, the lower raised portion 61b has an inclined portion 610 whose projecting length gradually increases from the upper side to the lower side, and a curved portion 611 that curves from the lower end of the inclined portion 610 to the intake intake pipe 7 side. . The protruding length (the length in the vehicle front-rear direction A) of the portion of the curved portion 611 that protrudes to the front side of the vehicle is longer than the protruding length of the upper raised portion 61a and the protruding length of the protruding portion 60.

  As shown in FIG. 6, the gas passage constituting member 10 includes a fixed portion 10a, a guide portion 10b, a through hole 10c, a gas outlet pipe portion 10d, and a collision wall portion 10e. Are integrally formed of synthetic resin.

  The fixed portion 10 a is formed in a ring shape along the outline of the root portion of the raised portion 61. The fixed portion 10a is fixed to the inner wall surface (surface on the vehicle rear side) 7a (see FIG. 5) of the surge tank 6 and the intake introduction pipe 7.

  The guide portion 10b is a plate-like portion facing the inner wall surface (vehicle rear surface) 7b (see FIG. 5) of the raised portion 61. The outer surface of the guide portion 10 b (the vehicle front side surface) has a shape along the ridgeline of the raised portion 61.

  The through hole 10c is a hole penetrating from the lower end portion of the guide portion 10b to the vehicle rear side.

  The gas outlet pipe portion 10d is a cylindrical portion extending from the vehicle rear side end portion of the through hole 10c to the vehicle rear side. That is, the gas outlet pipe portion 10 d extends from the outer wall side of the intake inlet pipe 7 toward the radial center. The distal end portion (the vehicle rear side end portion) of the gas outlet pipe portion 10d is located in the vicinity of the radial center portion of the intake air introduction pipe 7.

  The collision wall portion 10e is a plate-like portion curved in a U shape when viewed from above, and both end portions in the cylinder row direction C are supported by the tip end portion of the gas outlet tube portion 10d. As shown in FIG. 4, the collision wall portion 10 e is located near the central portion in the radial direction of the intake air introduction pipe 7.

  The EGR gas that has flowed into the gas introduction channel 8 from the EGR passage 9 flows through the gas introduction channel 8, is led out from the tip of the gas lead-out pipe part 10d, and collides with the collision wall part 10e. Since the EGR gas diffuses by colliding with the collision wall 10e, fresh air that flows into the intake air introduction pipe 7 through the throttle body 11 (see FIGS. 1 to 4) described later, and intake air through the oil separator 16 The blow-by gas flowing into the introduction pipe 7 is sufficiently mixed. As a result, an air-fuel mixture in which fresh air, EGR gas, and blow-by gas are sufficiently mixed is supplied into the cylinder of the engine 4 through the surge tank 6 and the intake pipe 5.

  The upper end of the throttle body 11 is connected to the lower end that is the upstream end of the intake pipe 7. A blow-by gas inlet 23 (see FIG. 4) is formed in the outer wall portion on the vehicle rear side in the longitudinal center portion of the intake air introduction pipe 7. The blow-by gas inlet 23 is connected to the downstream end of the blow-by gas passage 22. The blow-by gas passage 22 is a conduit that guides the blow-by gas from which the lubricating oil has been removed in the oil separator 16 to the intake air introduction pipe 7.

  The intake air introduction pipe 7 introduces fresh air supplied to the intake air introduction pipe 7 via an air cleaner (not shown) and the throttle body 11 with the EGR gas and blow-by gas into the surge tank 6. The intake pipe 7 is inclined forward and downward so that the central axis along the longitudinal direction thereof is lowered on the vehicle front side.

  As shown in FIG. 4, the throttle body 11 includes a throttle valve 11a that adjusts the intake amount of fresh air from which dust and dirt have been removed by an air cleaner, and a cylindrical valve case 11b that accommodates and holds the throttle valve 11a. Have. The valve case 11b is inclined forward and downward so that its central axis is lowered on the front side of the vehicle. The vehicle front side end portion of the throttle body 11 (the front side end portion of the valve case 11 b) protrudes further toward the vehicle front side than the protrusion 60 and the raised portion 61. A flexible pipe 17 (see FIGS. 3 and 4) that guides fresh air to the throttle body 11 is connected to the upstream end of the throttle body 11.

  A fragile portion 13 (see FIGS. 3 and 4) is formed in the vicinity of the upstream side end portion (the rear divided body 20) of the intake pipe 7 along the circumferential direction thereof. The fragile portion 13 is a thin portion formed with a thin wall thickness over the entire circumferential direction of the intake air introduction pipe 7.

  By making the wall thickness of the fragile portion 13 smaller than the wall thickness of other portions of the rear divided body 20 (for example, 2 mm), the strength of the fragile portion 13 is reduced. For example, as shown in FIG. 4, the wall thickness can be reduced by forming a groove (notch) having a V-shaped cross section in the intake air introduction pipe 7.

  As shown in FIGS. 3 and 4, a load receiving member 14 that receives the intake air introduction pipe 7 at the time of a frontal collision of the vehicle is provided behind the intake air introduction pipe 7 (the vehicle rear side). The load receiving member 14 has a load receiving surface 14a opposite to a vehicle rear side end surface (load transmitting surface 15c) in a load transmitting portion 15 to be described later, and the oil separator 16 is disposed on the front surface of the cylinder block 41 on the vehicle. Is fixed through.

  As shown in FIGS. 3 and 4, a load transmission portion 15 that protrudes from the surface to the vehicle rear side is provided on the surface of the intake air introduction pipe 7 on the vehicle rear side. As shown in FIG. 7, the load transmission unit 15 includes a plurality of projecting plates 15 a that project toward the vehicle rear side, and a connecting unit 15 b that couples the projecting plates 15 a to each other. A load transmitting surface 15c is formed at the vehicle rear side end of the plurality of protruding plates 15a.

  As shown in FIGS. 3, 4, and 7, there is a slight gap between the load receiving surface 14 a of the load receiving member 14 and the load transmitting surface 15 c of the load transmitting portion 15. By providing this gap, the vibration of the engine 4 when the engine 4 is operating is not directly transmitted to the throttle body 11 via the load receiving member 14 and the load transmitting portion 15.

  Next, how the intake manifold 2 is deformed when the vehicle has a frontal collision will be described.

  When a frontal collision occurs, as shown in FIG. 8A, the radiator R is displaced to the vehicle rear side, and the radiator R collides with the throttle body 11.

  Due to this collision, stress concentrates on the fragile portion 13 and a crack occurs in the fragile portion 13, and the fragile portion 13 is broken as shown in FIG. 8B, and the throttle body 11 is displaced to the vehicle rear side. While dropping off from the intake pipe 7. The impact of the collision is absorbed to some extent by the breakage of the fragile portion 13. Since the fragile portion 13 is quickly broken, the intake manifold 2 is not displaced rearward of the vehicle.

  When the radiator R is further displaced toward the vehicle rear side, the radiator R collides with the lower raised portion 61b. As a result of this collision, stress concentrates on the root portion of the lower raised portion 61b (the boundary portion with the intake air introduction pipe 7), a crack occurs in the root portion, and the root portion is broken. Due to this breakage, the impact of the collision is absorbed to some extent.

  When the radiator R is further displaced toward the rear side of the vehicle, a crack at the base portion of the lower raised portion 61b propagates to the periphery, and the crack spreads to the entire vehicle front side portion of the intake air introduction pipe 7.

  When the radiator R is further displaced toward the vehicle rear side, the radiator R collides with the protrusion 60. As a result of this collision, stress concentrates on the root portion of the protrusion 60 (the boundary portion with the surge tank 6), a crack is generated in the root portion, and the root portion is broken. Due to this breakage, the impact of the collision is absorbed to some extent.

  When the radiator R is further displaced toward the rear side of the vehicle, a crack at the base portion of the projecting portion 60 develops to the surroundings, and the crack spreads over the entire vehicle front side portion of the surge tank 6.

  When the radiator R is further displaced to the vehicle rear side, the vehicle front side portions of the surge tank 6 and the intake air introduction pipe 7 are crushed as shown in FIG. 8C. By collapsing the vehicle front side portions of the surge tank 6 and the intake intake pipe 7, the impact of the collision is considerably absorbed.

  Since the impact of the collision is considerably absorbed by the vehicle front side portion of the surge tank 6 and the intake introduction pipe 7, the vehicle rear side portion of the intake manifold 2 is not crushed as shown in FIG. Does not displace to Thereby, it is possible to effectively prevent the intake manifold 2 from interfering with the fuel distribution pipe 3.

  As described above, according to the present embodiment, the radiator R collides with the throttle body 11 before colliding with the intake manifold 2 at the time of front collision of the vehicle. Due to the impact of the collision with the throttle body 11, the fragile portion 13 is easily and quickly broken, so that the throttle body 11 is prevented from pressing the intake manifold 2 toward the vehicle rear side. Therefore, it is possible to suppress the intake manifold 2 from being displaced rearward of the vehicle and interfering with the fuel distribution pipe 3. Further, the impact of the collision is absorbed by the breakage of the fragile portion 13. Since the degree of breakage of the fragile portion 13 changes according to the amount of the collision partner entering the host vehicle, the impact can be appropriately absorbed according to the amount of the approach.

  Further, when the amount of the collision partner entering the own vehicle is large, the fragile portion 13 is completely broken, the throttle body 11 is dropped from the intake air introduction pipe 7, and the radiator R collides with the intake manifold 2. However, since the front divided body 21 is easily deformed, the impact of the collision is absorbed by the front divided body 21, and the deformation of the rear divided body 20 is suppressed. Therefore, it is possible to suppress the intake manifold 2 from interfering with the fuel distribution pipe 3.

  Further, since the cylinder block 41 of the engine 4 and the intake air introduction pipe 7 are not directly connected, it is possible to prevent the rigidity of the cylinder block 41 near the attachment position of the knock sensor from changing. Therefore, knocking can be accurately detected by the knock sensor. Further, it is possible to suppress vibration from being input from the cylinder block 41 side to the throttle valve 11a that requires high opening / closing accuracy to control the output of the engine 4.

  Further, since the load receiving member 14 receives the intake air introduction pipe 7 at the time of a frontal collision of the vehicle, the movement of the intake air introduction pipe 7 at the time of the frontal collision can be suppressed, and a shearing force is positively generated in the fragile portion 13. Thus, the breakage of the fragile portion 13 can be promoted. By promoting the breakage of the fragile portion 13, it is possible to promote the impact absorption due to the breakage of the fragile portion 13.

  Further, since the fragile portion 13 is formed by reducing the wall thickness in the vicinity of the upstream end portion of the intake air introduction pipe 7, the fragile portion 13 can be configured with a simple configuration.

  In addition, since the intake pipe 5, the surge tank 6, and the intake introduction pipe 7 are arranged in this order from the upper side to the lower side, the radiator R is connected to the intake pipe 5, the surge tank 6, It is possible to collide with the intake air introduction pipe 7, and the front part of the vehicle can be crushed widely into a flat shape to effectively absorb the impact of the collision.

  Further, at the time of a frontal collision of the vehicle, the protrusion 60 serves as a starting point for breaking the front portion of the intake manifold 2, and the breaking can be smoothly expanded from the starting point to the entire intake manifold 2. The front side portion is easily broken. This improves the shock absorption of the vehicle front side portion of the intake manifold 2, so that deformation of the vehicle rear side portion of the intake manifold 2 can be suppressed, and the vehicle rear side portion of the intake manifold 2 is connected to the fuel distribution pipe 3. Interference can be sufficiently suppressed.

  In the above embodiment, the fragile portion 13 is formed by reducing the wall thickness in the vicinity of the upstream end portion of the intake air introduction pipe 7 along the circumferential direction. However, the present invention is not limited to this. For example, the fragile portion may be formed by forming the vicinity of the upstream end portion of the intake pipe 7 with a material having low strength along the circumferential direction.

  Moreover, in the said embodiment, although EGR gas is introduce | transduced into the gas introduction flow path 8, it is not limited to this. For example, even if the purge gas obtained by purging the blow-by gas from which the lubricating oil has been removed by the oil separator 16 or the evaporated fuel adsorbed and held by the canister (not shown) is introduced into the gas introduction channel 8. Good.

  Moreover, in the said embodiment, although the projection part 60 is formed in square pyramid shape, it is not restricted to this. For example, the protrusion 60 may have another shape such as a truncated cone shape, a columnar shape, or a quadrangular prism shape.

  Moreover, in the said embodiment, although the curved part 611 of the lower side protruding part 61b protrudes ahead of the vehicle rather than the projection part 60, it is not restricted to this. The protrusion 60 may protrude toward the vehicle front side from the curved portion 611 of the lower raised portion 61b, or the position of the tip of the protrusion 60 in the vehicle longitudinal direction A and the vehicle front side end portion of the curved portion 611 The position may be the same.

DESCRIPTION OF SYMBOLS 1 Engine intake device 2 Intake manifold 3 Fuel distribution pipe 4 Engine 40 Cylinder head 5 Intake pipe 6 Surge tank 60 Projection part 61 Raised part 7 Intake introduction pipe 8 Gas introduction flow path 13 Fragile part 14 Load receiving member

Claims (4)

An engine intake device that is disposed horizontally in the engine room at the front of the vehicle so that the cylinder row direction faces the vehicle width direction,
A synthetic resin intake manifold disposed on the front side of the engine on the vehicle front side;
A throttle body that is connected to the intake manifold and adjusts the amount of intake air supplied to the intake manifold;
A fuel distribution pipe extending in the cylinder row direction between the engine and the intake manifold and supplying fuel to a fuel injection valve corresponding to each cylinder of the engine;
The intake manifold includes an intake pipe connected to an intake port of a cylinder head of the engine, a surge tank connected to an upstream end of the intake pipe, and an intake connected to an upstream end of the surge tank. The intake pipe is fixed to the cylinder head, and is supported in a cantilevered state by the cylinder head.
The throttle body is connected to an upstream end portion of the intake introduction pipe so as to protrude toward the vehicle front side from the intake manifold,
In the vicinity of the upstream end of the intake pipe, a fragile part is formed ,
In the vicinity of the intake pipe on the cylinder head side, a load receiving member that receives a portion of the intake pipe in the downstream side of the fragile portion at the time of a frontal collision of the vehicle is provided . Engine intake system. The intake manifold is composed of a rear division on the side close to the engine and a front division on the side far from the engine,
The intake device for an engine according to claim 1, wherein the strength of the front divided body is smaller than the strength of the rear divided body. 3. The engine intake device according to claim 1, wherein the fragile portion is formed by reducing a wall thickness in the vicinity of an upstream end portion of the intake intake pipe. The engine intake device according to any one of claims 1 to 3 , wherein the intake pipe, the surge tank, and the intake introduction pipe are arranged in this order from the upper side to the lower side. .

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