JP2005207346A - Engine intake device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve a fastening workability and a supporting strength of an intake device of an engine even if the device is constructed in dividing structure. <P>SOLUTION: An intake device 3 of an engine 2 is constructed in the dividing structure formed by an inlet manifold 4 arranged at one side of the engine, and by a surge tank member 5 having a branch passage section 6 communicating to the inlet manifold 4 and a surge tank section 7, and an upstream flange section 42 of the inlet manifold 4, on which the surge tank member 5 is attached, is made to incline in a slanting upper direction of the engine. Stays, which is brought into contact with counterparts in bolt fastening, are integrally formed at one side or both sides between a vicinity of an intake introducing section 71 of the above-mentioned surge tank member and a downstream flange section 44 of the inlet manifold 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

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

  An intake system of a multi-cylinder engine generally has a surge tank portion for introducing intake air and a plurality of independent branch passage portions communicating therewith to intake ports of the respective cylinders.

  One example is the invention disclosed in Patent Document 1. In the present invention, as shown in FIG. 9, the intake device 3 ′ is disposed on the side surface on the intake side of the in-line four-cylinder engine 2 ′. The intake device 3 ′ communicates with the intake port of the engine 2 ′, is divided into four parts, extends from the side of the engine 2 ′ to the outside of the engine 2 ′, and is bent downward, A common passage in which the branch passage portion 6 'is gathered is formed on one side of the engine 2', and has a surge tank portion 7 'to which a throttle unit is attached at an upstream end portion thereof. Here, the branch passage portions 6 'are arranged in parallel at a predetermined interval in the cylinder row direction. When the intake device 3 ′ is fastened to the engine 2 ′, the flange portion 62 ′ at the downstream end of the branch passage portion 6 ′ is bolted to the engine 2 ′ in a staggered manner using the above-described distance. Yes.

  By the way, in the intake device 3 ′, a surge tank portion 7 ′, to which a throttle unit is attached, is extended to one side of the engine 2 ′ at the upstream end portion, and is unbalanced in weight. . Therefore, it is necessary to increase the support strength of the intake device 3 'with respect to the engine 2'.

As an example of this improvement measure, there is an invention disclosed in Patent Document 2. According to the present invention, in addition to the original fastening portion such as the flange portion at the downstream end of the branch passage portion, it is fastened and supported by the stay of another component to improve the support strength for the engine.
Japanese Patent Laid-Open No. 11-210576 JP-A-10-252588

  However, in recent years, the volume of the engine room tends to become smaller in accordance with the promotion of the compactness of the vehicle against the background of improved fuel efficiency. As a result, there is a demand for reducing the outer dimensions of the engine.

  However, in the invention described in Patent Document 1, the branch passage portions 6 ′ are arranged in parallel with a predetermined interval in the cylinder row direction of the engine 2 ′, and further on the further side of the branch passage portion 6 ′. A throttle unit protrudes toward the side, and the outer dimension in the engine cylinder row direction is large.

  In order to reduce the outer dimension of the engine 2 'in the cylinder row direction, it is advantageous to arrange the intervals of the branch passage portions 6' closely. However, if the intervals between the branch passage portions 6 ′ are made dense, bolts cannot be passed between the branch passage portions 6 ′ as in Patent Document 1, and the flange portion 62 ′ at the downstream end portion is connected to the engine. It becomes difficult to secure a bolt fastening work space for fastening to 2 ′, and the difficulty increases as the pitch between the bores of the engine 2 ′ decreases.

  Therefore, the engine intake device is divided into a main body portion including a branch passage portion and a surge tank portion, and an attachment portion interposed between the main body portion and the engine, and the attachment portion is attached to the engine. Later, it is conceivable to attach the main body part to the attachment part. However, since the intake device is a component that requires a support strength sufficient to withstand engine vibration, when the intake device has a split structure, the fastening structure of each component becomes a problem.

  Further, as described above, the upstream common passage is formed in one side of the engine with a predetermined length in the surge tank portion of the intake device, and a throttle unit is attached to the tip portion of the surge tank portion. Even unbalanced. Therefore, it is also necessary to improve the support strength of the intake device while taking into account weight imbalance.

  The present invention has been made in view of such a point, and an object thereof is to improve the fastening workability and the support strength when the intake device has a split structure.

  The first invention is directed to an intake device for an engine having a plurality of intake ports that open to one side of an in-line multi-cylinder engine and guide intake air to each cylinder individually.

  A surge tank portion disposed on one side of the engine; and a plurality of a plurality of tanks that communicate with the opposite side of the surge tank portion to the engine side and extend upward while curving toward the opening of each intake port. A branch passage portion composed of a branch pipe and an intake air introduction portion which communicates with the upstream side of the surge tank portion and opens at a side position in the cylinder row direction of the branch passage portion and to which a throttle unit is attached are integrally formed. A plurality of independent passages that are interposed between the formed surge tank member, the downstream end portion of the branch passage portion, and the intake port of the engine and communicate with the branch pipes and the intake ports are integrated. And an intake manifold formed in the above.

  The intake manifold has a downstream flange portion attached to one side of the engine by bolt fastening, and an upstream flange portion to which a downstream end portion of the branch passage portion is attached. The side flange portion is provided at a predetermined angle with respect to the mounting surface of the downstream flange portion so that the mounting surface faces obliquely upward outward of one side of the engine, and the branch passage portion includes the upstream flange A mounting flange portion that is bolted to the portion.

  Furthermore, the intake part of the surge tank member, the intake manifold, and the downstream flange part are integrally formed with connecting parts that are connected to each other in the vicinity of the opening of the intake inlet part. Two connecting parts are bolted.

  In the case of the above configuration, the intake air introduced from the intake air introduction portion is introduced into the branch passage portion by the intake device, and the intake air is supplied to each intake port of the engine. The intake device has a divided structure of the surge tank member and the intake manifold. The surge tank member includes an upstream surge tank portion and a downstream branch passage portion. The surge tank portion introduces intake air from an intake air introduction portion provided at the upstream end portion thereof, absorbs pressure fluctuations of the intake air, and sends the intake air to the downstream branch passage portion. In the branch passage portion, each branch pipe is independent and guides intake air into the intake manifold on the downstream side. The intake manifold is independent in each passage and communicates with each intake port of the engine individually. The introduced intake air is supplied to each cylinder of the engine through each intake port.

  Next, attachment of the engine, intake manifold and surge tank member will be described. The intake manifold has the downstream flange portion bolted to the engine, and the surge tank member has the mounting flange portion bolted to the upstream flange portion of the intake manifold. At this time, the intake manifold is bolted vertically to one side of the engine. On the other hand, the joint surface between the intake manifold and the surge tank member is angled obliquely upward with respect to one side of the engine, so that the bolt is fastened from obliquely above the engine. This makes it possible to secure a sufficient bolt fastening work space for fastening the surge tank member to the intake manifold. Here, when the mounting surface of the upstream flange portion of the intake manifold and the mounting surface of the downstream flange portion are formed in parallel, the joint surface between the intake manifold and the surge tank member is parallel to the engine side surface. Thus, the bolt is fastened to the engine from the horizontal direction. Further, when the surge tank member is attached, it is preferable to fasten several bolts on the downstream flange portion so as to surround the branch passage portion. However, the branch passage portion extends to the side of the engine and curves downward. Therefore, when the lower end of the downstream flange portion, that is, the lower position of the branch passage portion is bolted, the branch passage portion is extended. The branch passage portion is located on the axis of the bolt, and the bolt fastening tool is likely to interfere with the branch passage portion, resulting in poor workability. Therefore, as described above, by adopting a structure in which the joint surface is directed obliquely upward, the bolt can be fastened from obliquely above the engine where the branch passage portion is not located, and a bolt fastening work space can be secured. . This structure is particularly effective when the bolt fastening operation of the surge tank member cannot be performed from the direction facing the engine side surface because the intervals between the branch passage portions are narrow.

  Further, since a throttle unit is attached to the intake air introduction portion of the surge tank member, the weight near the intake air introduction portion becomes heavy. Therefore, the connection strength provided in the vicinity of the opening of the intake air introduction portion and the connection portion provided in the intake manifold are bolted to improve the support strength of the surge tank member against engine vibration. In addition, since these connecting portions are formed integrally with the intake air introduction portion and the downstream flange portion of the intake manifold, the rigidity is high.

  Therefore, when the intake system of the engine has a split structure of the intake manifold and surge tank member, the support strength against engine vibration is improved without increasing the number of separate parts while securing the workability of the surge tank member. Can be made.

  In a second aspect based on the first aspect, the surge tank member further includes a main stay fastened to one side surface of the engine, and the main stay includes the surge in a state where the throttle unit is attached. It is assumed that the tank member is provided at a position substantially corresponding to the position of the center of gravity in the cylinder row direction.

  In the case of the configuration described above, the surge tank portion of the surge tank member has an intake introduction portion to which a throttle unit is attached extending toward one side in the cylinder row direction. For this reason, the center of gravity of the surge tank member is eccentric to one side in the cylinder row direction by the weight of the surge tank portion and the throttle unit. Therefore, in the cylinder row direction, the main stay is provided at a position corresponding to the eccentric center of gravity position, thereby correcting the weight imbalance of the surge tank member.

  Therefore, the support strength of the whole intake device can be further improved.

  In a third aspect based on the second aspect, the intake manifold is made of metal, and the surge tank member is made of resin.

  In the case of the above configuration, the surge tank member can be reduced in weight and cost, and as a result, the overall weight and cost of the intake device can be realized.

  In a fourth aspect based on the third aspect, the connecting portion of the downstream flange portion is provided on a stay extending from a bolt fastening portion of the downstream flange portion with respect to the engine.

  In the case of the above configuration, the stay is formed because the stay is formed on the metal intake manifold, and the connecting portion is formed on the stay. Furthermore, the stay is further formed by extending the stay integrally from a bolt fastening portion to the engine of the downstream flange portion instead of forming a stay at an arbitrary position of the downstream flange portion. be able to.

  Therefore, the support strength of the surge tank member can be further increased by increasing the rigidity of the stay.

  According to a fifth invention, in the first invention, the branch pipes of the branch passage section are arranged in a state where the upstream side portions thereof are densely arranged in the cylinder row direction, and the downstream side portions thereof are spaced in the cylinder row direction. It is assumed that the intake air introduction portion opens at a side position in the cylinder row direction in the upstream portion of the branch pipe.

  In the case of the above configuration, the upstream portion of the branch pipe of the branch passage portion is closely arranged in the cylinder row direction, and the intake air introduction portion is located at a side position in the cylinder row direction in the upstream portion. Therefore, the outer dimension of the entire intake device in the cylinder row direction is reduced.

  Further, since the upstream portion is densely formed in the cylinder row direction, when the surge tank member is fastened to the intake manifold, the bolt fastening work space is formed from the direction facing the engine side surface in the upstream portion. It is difficult to secure. However, as the downstream portion is curved toward the engine side, the interval between the passages increases, and the joint surface between the upstream flange portion of the intake manifold and the mounting flange portion of the surge tank member is obliquely above the outside of the engine. Therefore, a sufficient bolt fastening work space can be ensured from an obliquely upper part of the engine at the downstream side portion where each branch pipe of the branch passage portion is expanded.

  Therefore, when the intake structure of the engine is a divided structure of the intake manifold and the surge tank member, it is sufficient to fasten the surge tank member to the intake manifold while reducing the outer dimension in the engine cylinder row direction. A working space can be secured.

  In a sixth aspect based on the first aspect, the upstream flange portion of the intake manifold is formed with a notch portion for fastening the bolt on the axis of the fastening bolt with respect to the engine of the downstream flange portion. It shall be.

  In the case of the above configuration, a notch portion for bolt fastening work is formed on the axis of the bolt of the upstream flange portion so that the tool does not interfere when the intake manifold is bolted to the side surface of the engine. Has been. Thereby, the fastening operation of the intake manifold to the engine can be performed smoothly.

  According to the engine intake device of the present invention, when the intake device has a divided structure of the intake manifold and the surge tank member, the support strength against vibrations of the engine is different while securing the workability of the surge tank member. Improvements can be made without increasing the number of parts.

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

  FIG. 1 shows a plan view of an engine according to an embodiment of the present invention disposed in an engine room. Here, in this embodiment, for convenience of explanation, the vertical direction of the vehicle is simply abbreviated as the vertical direction, and in the following description, upstream and downstream are upstream with respect to the flow direction of intake air introduced into the engine. And downstream.

  Reference numeral 1 denotes an engine room at the front of the vehicle, 2 denotes an engine main body disposed in the engine room 1, and 3 denotes an intake device constituted by an intake manifold 4 and a surge tank member 5.

  As shown in FIG. 1, a dash panel 11 that partitions a vehicle compartment (not shown) and the engine room 1 is provided at the rear end of the engine room 1. At the center of the dash panel 11 in the vehicle width direction, an engine installation recess 11a is provided in the rear. In the engine room 1, a pair of left and right front side frames 15, 15 extending in the front-rear direction and having a predetermined interval in the vehicle width direction are disposed.

  As shown in FIG. 1, the engine 2 is disposed vertically between the left and right front side frames 15 and 15 so that the cylinder row direction faces the vehicle front-rear direction. At this time, the rear end portion of the engine 2 is positioned in the engine placement recess 11 a of the dash panel 11. Further, engine functional parts such as an air cleaner 8 and a battery 9 are located in front of the engine 2. That is, since the engine 2 is disposed in a narrow space in the engine room 1, it is required to make its outer dimension as small as possible.

  Further, the engine 2 is an in-line four-cylinder engine in which four cylinders 21, 21,... Are arranged in series as shown in FIG. The intake ports 22, 22,... Communicating with the cylinders 21, 21,... Are formed at predetermined intervals in the cylinder row direction.

  As shown in FIGS. 1 and 2, the intake device 3 is attached to the left side surface of the engine 2 so as to communicate with the intake ports 22, and intake air is supplied from the intake device 3 to the cylinders 21. The The intake device 3 has a divided structure including an intake manifold 4 on the downstream side and a surge tank member 5 on the upstream side.

  As shown in FIGS. 3 and 4, the intake manifold 4 has four independent passages 41, 41,... Made of aluminum or the like integrally formed by an upstream flange portion 42 and a downstream flange portion 44 at both end openings. It is a metal part. The independent passages 41, 41,... Are arranged in parallel in the cylinder row direction, and are referred to as a first independent passage 41, a second independent passage 41,. The intake manifold 4 is assembled to the engine 2 with the downstream flange portion 44 facing the left side surface of the engine 2 (see FIG. 2).

  As shown in FIG. 2, the independent passages 41, 41,... Extend obliquely upward from the downstream flange portion 44, and the upstream flange portion 42 is connected to the independent passages 41, 41,. It is formed substantially perpendicular to. That is, the upstream flange portion 42 has an attachment surface 42 a facing obliquely upward, and is angled with respect to the attachment surface 44 a of the downstream flange portion 44. Further, as shown in FIGS. 3 and 4, four upstream openings that communicate with the independent passages 41, 41,... Are respectively provided on the mounting surface 42 a of the upstream flange portion 42 and the mounting surface 44 a of the downstream flange portion 44. 41a, 41a, ... and four downstream openings 41b, 41b, ... are formed. The downstream openings 41b, 41b,... Are provided at the same intervals as the intake ports 22, 22,.

  As shown in FIG. 3, the downstream flange portion 44 has five bolt holes 45a, 45b,..., 45e as bolt fastening portions to the engine 2 of the downstream flange portion 44 in order from the front of the vehicle. It penetrates and is formed perpendicularly to the downstream flange 44 so as to sandwich each downstream opening 41b. Of the bolt holes 45a, 45b,..., 45e, the bolt holes 45a, 45c, 45e at both side ends and the central part are provided at the lower end of the downstream flange portion 44, while the first independent passage 41 and the second independent passage are provided. Bolt holes 45 b and 45 d between the passage 41 and between the third independent passage 41 and the fourth independent passage 41 are arranged in a staggered manner so as to be located at the upper end portion of the downstream flange portion 44. Further, as shown in FIG. 2, the bolt hole 45 a located outside the first independent passage 41 has a boss portion 44 c extending perpendicularly to the downstream flange portion 44 and extending toward the upstream flange portion 42. Is formed. The boss portion 44c is integrally formed with a stay 44d that extends to the lower front side of the vehicle and has a manifold side connecting portion 44e at the tip. A screw hole 44f is formed through the manifold side connecting portion 44e.

  The downstream flange portion 44 is bolted to the left side surface of the engine 2 through the bolt holes 45a, 45b,. At this time, the downstream side openings 41b, 41b, ... of the independent passages 41, 41, ... communicate with the intake ports 22, 22, ....

  As shown in FIG. 4, the upstream flange portion 42 has five screw holes 43a, 43b,..., 43e in order from the front of the vehicle, as shown in FIG. And is formed so as to penetrate perpendicularly to the upstream side flange portion 42. Of the screw holes 43a, 43b,..., 43e, the screw holes 43a, 43c, 43e at both end portions and the central portion are provided at the lower end portion of the upstream flange portion 42, and on the other hand Screw holes 43b and 43d between the passage 41 and between the third independent passage 41 and the fourth independent passage 41 are arranged in a staggered manner so as to be located at the upper end portion of the upstream flange portion. In addition, the downstream flange is formed in a portion located between the first independent passage 41 and the second independent passage 41 and between the third independent passage 41 and the fourth independent passage 41 of the upstream flange portion 42. Notches 42b and 42b for bolting the portion 44 to the engine 2 are formed. The notches 42 b and 42 b are notched in such a size that the fastening tool does not interfere with the upstream flange portion 42 in the axial direction of the fastening bolt to the engine 2.

  3 and 4, an opening 46 constituting a vacuum chamber is formed between the second independent passage 41 and the third independent passage 41. Further, as shown in FIG. 5, a swirl control valve actuator 47 is disposed on the vehicle rear side of the fourth independent passage 41 of the intake manifold 4, and is variable on the vehicle rear side of the surge tank member 5. Valve actuators 65 are located, and each is connected to the vacuum chamber by a negative pressure circuit. A negative pressure is stored in the vacuum chamber, and the swirl control valve actuator 47 and the variable valve actuator 65 are operated by the negative pressure.

  As shown in FIGS. 2, 6, and 7, the surge tank member 5 includes a downstream branch passage portion 6 and an upstream surge tank portion 7. As shown in FIG. 2, the surge tank member 5 is a synthetic resin part in which injection molded parts 5a, 5b, and 5c divided into three in the vehicle width direction are joined by, for example, vibration welding. By making the surge tank member 5 made of synthetic resin, the entire intake device 3 is reduced in weight and cost.

  As shown in FIGS. 6 and 7, the branch passage section 6 is integrally formed with four branch pipes 61, 61,... Communicating with the independent passages 41, 41,. A first branch pipe 61, a second branch pipe 61,. An attachment flange portion 62 for attaching the surge tank member 5 to the intake manifold 4 is provided at the downstream end portion of the branch passage portion 6. The branch pipes 61 are connected by a thin rib member 64a. Further, the first branch pipe 61 and the surge tank portion 7 are also reinforced by the rib member 64b.

  The mounting flange portion 62 has five bolt holes 63a, 63b,..., 63e for bolting the surge tank member 5 to the intake manifold 4 in order from the front of the vehicle, and the opening 62b of each branch pipe 61. A through hole is formed so as to be sandwiched and perpendicular to the mounting flange portion 62. Of the bolt holes 63a, 63b,... 63e, the bolt holes 63a, 63c, 63e at both end portions and the central portion are provided at the lower end portion of the mounting flange portion 62, while the first branch pipe 61 and the second branch pipe 61 are provided. The bolt holes 63b and 63d between the third branch pipe 61 and the fourth branch pipe 61 are arranged in a staggered manner so as to be located at the upper end of the mounting flange portion 62. The bolt holes 63a, 63b,..., 63e are provided at positions communicating with the screw holes 43a, 43b,..., 43e when the surge tank member 5 is assembled to the intake manifold 4. In order to prevent the fastening tool from interfering with the rib members 64a and 64b when the mounting flange portion 62 is bolted, the rib members 64a and 64b have portions intersecting the axis of the bolt holes 63a and 63c, respectively. Interference avoiding holes 64c and 64d are formed.

  The openings 62b, 62b, ... of the branch pipes 61, 61, ... formed on the attachment surface of the attachment flange 62 are formed at the same intervals as the upstream openings 41a, 41a, ... of the intake manifold 4. When the surge tank member 5 is attached to the intake manifold 4, the individual passages 41 of the intake manifold 4 and the branch pipes 61 of the surge tank member 5 communicate with each other.

  As shown in FIG. 2, the branch pipes 61, 61,... Extend downstream from the joint with the intake manifold 4 obliquely upward to the left of the vehicle and then bend downward as a downstream part that curves downward. 61a, 61a,..., And downstream branch pipes 61a, 61a,... And upstream branch pipes 61b, 61b,. Is done. And the upstream edge part of this upstream branch pipe 61b, 61b, ... communicates with the said surge tank part 7. FIG. As shown in FIGS. 5 and 6, with respect to the cylinder row direction, the upstream branch pipes 61b extend upward in parallel and densely with each other, and the downstream branch pipes 61a continuous therewith Is extended to an interval communicating with the intake manifold 4.

  The surge tank section 7 communicates with the branch passage section 6 at the downstream end thereof at the upstream end of the upstream branch pipe 61b, and the branch pipes 61, 61,. It has become. The surge tank portion 7 is disposed between the engine 2 and the upstream branch pipe 61b, and the upstream side extends forward of the vehicle along the cylinder row direction. Further, as shown in FIG. 6, an intake air inlet 71 having a throttle unit mounting portion 72 a is provided at the upstream end thereof, and the intake air inlet 71 is connected to the first branch pipe 61. When viewed from the front of the vehicle, it is positioned immediately in front of the upstream branch pipe 61b, and the intake air introduction portion 71 and the upstream branch pipe 61b overlap as shown in FIG.

  Therefore, the surge tank member 5 has the branch pipes 61, 61,... And the surge tank portion 7 formed densely in the cylinder row direction, and has a small outer dimension.

  A throttle unit 72 is attached to the intake air introduction portion 71, and an air cleaner 8 in front of the engine 2 is connected to the throttle unit 72 as shown in FIG.

  Then, the intake air purified by the air cleaner 8 is introduced into the surge tank 7 by controlling the intake amount by the throttle unit 72. Then, the intake air is distributed from the surge tank portion 7 to each branch pipe 61 and is supplied to each intake port 22 of the engine 2 through each branch pipe 61 and through each independent passage 41 of the intake manifold 4. The

  In addition, as shown in FIG. 8, the branch short pipe 61c which connects each branch pipe 61 and the surge tank part 7 is provided in the intermediate part in each upstream branch pipe 61b of the said branch passage part 6, The branch short pipe 61c is opened and closed by an open / close valve 61d provided in the branch short pipe 61c. Thereby, the overall length of the intake passage from the surge tank portion 7 to each intake port 22 is variable. The opening / closing valve 61d is operated by a variable valve actuator 65 shown in FIG.

  As shown in FIGS. 6 and 7, a main stay 74 for fixing the surge tank portion 7 to the engine 2 is extended downward at the lower end portion of the surge tank portion 7. A bolt hole 74 a penetrating in a direction perpendicular to the side surface of the engine 2 is formed at the tip of 74. The position of the main stay 74 in the cylinder row direction is a position that substantially corresponds to the position of the center of gravity when the throttle unit 72 is attached to the intake air introduction portion 71.

  Further, as shown in FIG. 7, a stay 73 is provided in the vicinity of the opening of the intake air introduction portion 71 at the upstream end portion of the surge tank portion 7. The stay 73 extends from the surge tank portion 7 to the lower front side of the vehicle, and a surge tank side connecting portion 73a is formed at the tip thereof. A bolt hole 73b is formed through the surge tank side connecting portion 73a. Further, in the state where the surge tank member 5 is attached to the intake manifold 4, the bolt hole 73b communicates with the screw hole 44f of the manifold side connecting portion 44e as shown in FIG. The surge tank side connecting portion 73a is bolted to the manifold side connecting portion 44e.

  The attachment of the intake device 3 configured as described above to the engine 2 will be described. First, the intake manifold 4 is attached to the left side surface of the engine 2. The intake manifold 4 is firmly fixed to the engine 2 in a zigzag manner by bolts 44b, 44b,. At this time, as shown in FIG. 4, the bolt holes 45a, 45b,..., 45e of the downstream flange portion 44 are located at the lower ends of the bolt holes 45a, 45b,. Since each of the independent passages 41 extends obliquely upward and the upstream flange portion 42 faces obliquely upward, the bolt can be fastened without interfering with the upstream flange portion 42. Further, bolt holes 45 b and 45 d between the first independent passage 41 and the second independent passage 41 located at the upper end portion of the downstream flange portion 44 and between the third independent passage 41 and the fourth independent passage 41. Also, notches 42b and 42b are formed in the upstream flange portion 42 between the first independent passage 41 and the second independent passage 41 and between the third independent passage 41 and the fourth independent passage 41. Therefore, the bolt can be fastened without interfering with the upstream flange portion 42.

  Further, the area of each notch portion 42b necessary for fastening the bolt from the horizontal direction of the engine 2 is such that both the flange portions 42 and 44 face each other because the upstream flange portion 42 faces obliquely upward. Smaller than the case. For this reason, the rigidity of the upstream flange portion 42 can be sufficiently ensured.

  Next, the surge tank member 5 is attached to the intake manifold 4. The bolt holes 63a, 63b, ..., 63e of the mounting flange portion 62 are bolted to the screw holes 43a, 43b, ..., 43e of the upstream flange portion 42 by five bolts 62a, 62a, .... At this time, as shown in FIGS. 2 and 6, the bolt holes 63a and 63c are bolted from above the surge tank member 5 through the interference avoidance holes 64c and 64d. That is, the surge tank member 5 can be attached to the intake manifold 4 while securing a sufficient working space from an obliquely upper side of the engine 2. At the same time, the bolts can be fastened to the upstream flange portion 42 and the mounting flange portion 62 from a substantially vertical direction where the fastening efficiency is maximized.

  Here, when the mounting surface 42a of the upstream flange portion 42 and the mounting surface 44a of the downstream flange portion 44 are not angled and the mounting surfaces 42a, 44a are arranged in parallel, the surge tank member 5 The joint surface to the intake manifold 4 is in the vertical direction, and the surge tank member 5 is attached to the intake manifold 4 from the horizontal direction with respect to the engine. As can be seen from a comparison between FIG. 5 and FIG. 9, each of the branch passage portions 6 ′ has conventionally had a predetermined interval in the cylinder row direction. The bolt could be fastened. However, in the present embodiment, the upstream branch pipes 61b, 61b,... Are arranged close together in the cylinder row direction, so that the upstream branch pipes 61b, 63b,. 61b, ... are positioned, and it is difficult to bolt the surge tank member 5 from the horizontal direction with respect to the engine.

  Therefore, inclining the joint surface of the surge tank member 5 obliquely upward of the engine 2 is effective for the engine when the branch pipes are closely arranged in the cylinder row direction or when the pitch between the bores of the engine 2 is small. On the other hand, it is particularly effective when it is difficult to attach the surge tank member 5 from the horizontal direction.

  Inclining the joint surface of the surge tank member 5 obliquely upward of the engine 2 is because the intake device 3 is divided, that is, with respect to the engine side surface (the mounting surface 44a of the downstream flange portion 44). This is easily realized by separately providing the intake manifold 4 having an angled mounting surface (the mounting surface 42a of the upstream flange portion 42).

  As shown in FIG. 2, the surge tank side connecting portion 73a is bolted to the manifold side connecting portion 44e. As a result, the vicinity of the opening of the intake air introduction portion 71, which has increased in weight due to the attachment of the throttle unit 72, is supported in a reinforcing manner, and the surge tank member 5 is fixed with a support strength that can withstand vibration of the engine 2. Since the stay 44d is formed integrally with the boss portion 44c of the bolt hole 45a for fastening the intake manifold 4 to the engine, the manifold side connecting portion 44e is supported with high rigidity.

  Furthermore, as shown in FIG. 5, the main stay 74 is bolted to the left side surface of the engine 2. Thus, the support strength is further improved by reinforcingly supporting the surge tank member 5 in a state where the throttle unit 72 is attached at the position of the center of gravity in the cylinder row direction.

  Therefore, even when the intake device 3 has a divided structure, the engine 2 and the intake manifold 4 and the intake manifold 4 and the surge tank member 5 are fastened in a zigzag manner so that they can be firmly fixed. it can. Further, by supporting the manifold side connecting portion 44e, the surge tank side connecting portion 73a, and the main stay 74 in a reinforcing manner, the support strength can be further increased without increasing the number of separate parts.

  Further, the workability of fastening the surge tank member 5 can be improved by inclining the joint surface between the divided intake manifold 4 and the surge tank member 5 obliquely upward of the engine 2. This is particularly effective when the intake device 3 is configured in a compact manner. As a result, the outer dimension of the engine 2 can be reduced, and the engine room 1 can be made compact.

<< Other Embodiments >>
The present invention may be configured as follows with respect to the above embodiment. That is, in the case of the above configuration, the engine 2 is arranged vertically in the engine room 1, but the engine 2 may be arranged horizontally so that the cylinder row direction is along the vehicle width direction. Even in such a case, when the intake device 3 has a divided structure of the intake manifold 4 and the surge tank member 5, the strength of supporting the vibration of the engine 2 is secured while securing the workability of the surge tank member 5. Can be improved without increasing the number of separate parts.

  In the case of the above configuration, the intake manifold 4 is a metal part, but may be made of a synthetic resin. With this configuration, the engine 2 can be reduced in weight, and as a result, fuel efficiency can be improved.

  Further, in the case of the above configuration, the manifold side connecting portion 44e and the surge tank side connecting portion 73a are bolted to improve the support strength of the surge tank member 5, but the stay 73 is not provided and the manifold side is provided. The connecting portion 44e may be directly bolted to the surge tank member 5, or the surge tank side connecting portion 73a may be directly bolted to the intake manifold 4 without providing the stay 44d.

It is a plane explanatory view showing the engine room of the front part of the vehicle concerning the embodiment of the present invention. It is the partial sectional view which looked at the intake device attached to the engine from the engine front. It is the rear view seen from the engine inside of the intake manifold. It is the front view seen from the engine outside of the intake manifold. It is the left view seen from the vehicle left side of an engine. It is the front view seen from the direction which opposes the attachment flange part of a surge tank member. It is the rear view seen from the direction which opposes the attachment flange part of a surge tank member. FIG. 8 is a cross-sectional explanatory view taken along line AA in FIG. 7. 1 is a front view of an engine disclosed in Patent Document 1. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Engine room 2 Engine 21 Cylinder 22 Intake port 4 Intake manifold 41 Independent passage 42 Upstream flange part 42b Notch part 44 Downstream flange part 44e Manifold side connection part (connection part)
5 Surge tank member 6 Branch passage part 61a Downstream branch pipe (downstream part)
61b Upstream branch pipe (upstream part)
62 Mounting flange portion 7 Surge tank portion 71 Intake inlet portion 72 Throttle unit 72a Throttle unit mounting portion 73a Surge tank side connecting portion (connecting portion)
74 Main stay

Claims (6)

An engine intake device having a plurality of intake ports that open to one side of an in-line multi-cylinder engine and guide intake air to each cylinder individually,
A surge tank portion disposed on one side of the engine, and a plurality of branch pipes communicating with the opposite side of the surge tank portion to the engine side and extending upward while curving toward the opening of each intake port And an intake air introduction portion that communicates with the upstream side of the surge tank portion and opens at a side position in the cylinder row direction of the branch passage portion and to which the throttle unit is attached. A surge tank member,
An intake manifold that is interposed between a downstream end of the branch passage portion and the intake port of the engine, and that is formed integrally with a plurality of independent passages that communicate the branch pipes with the intake ports; With
The intake manifold has a downstream flange portion attached to one side of the engine by bolt fastening, and an upstream flange portion to which a downstream end portion of the branch passage portion is attached, and the upstream flange The portion is provided at a predetermined angle with respect to the mounting surface of the downstream flange portion so that the mounting surface faces obliquely upward on one side outward of the engine,
The branch passage portion has a mounting flange portion that is bolted to the upstream flange portion,
In the intake inlet portion of the surge tank member and the downstream flange portion of the intake manifold, a connecting portion that is connected to the other side is integrally formed in the vicinity of the opening of the intake inlet portion, and the two connecting portions are integrally formed. Engine intake device characterized in that the part is bolted. The engine intake device according to claim 1,
The surge tank member further has a main stay fastened to one side of the engine,
The engine intake device according to claim 1, wherein the main stay is provided at a position substantially corresponding to a position of a center of gravity of the surge tank member in a cylinder row direction in a state where the throttle unit is attached. The engine intake device according to claim 2,
The intake manifold is made of metal,
An intake device for an engine, wherein the surge tank member is made of resin. The engine intake device according to claim 3,
The engine intake device according to claim 1, wherein the connecting portion of the downstream flange portion is provided on a stay extending from a bolt fastening portion of the downstream flange portion to the engine. The engine intake device according to claim 1,
The branch pipes of the branch passages are arranged so that their upstream portions are densely arranged in the cylinder row direction and their downstream portions are widened in the cylinder row direction,
The intake system for an engine according to claim 1, wherein the intake air introduction portion opens at a side position in a cylinder row direction in an upstream portion of the branch pipe. The engine intake device according to claim 1,
An intake system for an engine, characterized in that a notch portion for bolt fastening work is formed in an upstream flange portion of the intake manifold on an axis of a fastening bolt for the engine of the downstream flange portion.

Images